anno_start anno_end anno_text entity_type sentence section 0 4 Haem chemical Haem-dependent dimerization of PGRMC1/Sigma-2 receptor facilitates cancer proliferation and chemoresistance TITLE 15 27 dimerization oligomeric_state Haem-dependent dimerization of PGRMC1/Sigma-2 receptor facilitates cancer proliferation and chemoresistance TITLE 31 37 PGRMC1 protein Haem-dependent dimerization of PGRMC1/Sigma-2 receptor facilitates cancer proliferation and chemoresistance TITLE 38 45 Sigma-2 protein Haem-dependent dimerization of PGRMC1/Sigma-2 receptor facilitates cancer proliferation and chemoresistance TITLE 0 42 Progesterone-receptor membrane component 1 protein Progesterone-receptor membrane component 1 (PGRMC1/Sigma-2 receptor) is a haem-containing protein that interacts with epidermal growth factor receptor (EGFR) and cytochromes P450 to regulate cancer proliferation and chemoresistance; its structural basis remains unknown. ABSTRACT 44 50 PGRMC1 protein Progesterone-receptor membrane component 1 (PGRMC1/Sigma-2 receptor) is a haem-containing protein that interacts with epidermal growth factor receptor (EGFR) and cytochromes P450 to regulate cancer proliferation and chemoresistance; its structural basis remains unknown. ABSTRACT 51 67 Sigma-2 receptor protein Progesterone-receptor membrane component 1 (PGRMC1/Sigma-2 receptor) is a haem-containing protein that interacts with epidermal growth factor receptor (EGFR) and cytochromes P450 to regulate cancer proliferation and chemoresistance; its structural basis remains unknown. ABSTRACT 74 97 haem-containing protein protein_type Progesterone-receptor membrane component 1 (PGRMC1/Sigma-2 receptor) is a haem-containing protein that interacts with epidermal growth factor receptor (EGFR) and cytochromes P450 to regulate cancer proliferation and chemoresistance; its structural basis remains unknown. ABSTRACT 118 150 epidermal growth factor receptor protein_type Progesterone-receptor membrane component 1 (PGRMC1/Sigma-2 receptor) is a haem-containing protein that interacts with epidermal growth factor receptor (EGFR) and cytochromes P450 to regulate cancer proliferation and chemoresistance; its structural basis remains unknown. ABSTRACT 152 156 EGFR protein_type Progesterone-receptor membrane component 1 (PGRMC1/Sigma-2 receptor) is a haem-containing protein that interacts with epidermal growth factor receptor (EGFR) and cytochromes P450 to regulate cancer proliferation and chemoresistance; its structural basis remains unknown. ABSTRACT 162 178 cytochromes P450 protein_type Progesterone-receptor membrane component 1 (PGRMC1/Sigma-2 receptor) is a haem-containing protein that interacts with epidermal growth factor receptor (EGFR) and cytochromes P450 to regulate cancer proliferation and chemoresistance; its structural basis remains unknown. ABSTRACT 5 30 crystallographic analyses experimental_method Here crystallographic analyses of the PGRMC1 cytosolic domain at 1.95 Å resolution reveal that it forms a stable dimer through stacking interactions of two protruding haem molecules. ABSTRACT 38 44 PGRMC1 protein Here crystallographic analyses of the PGRMC1 cytosolic domain at 1.95 Å resolution reveal that it forms a stable dimer through stacking interactions of two protruding haem molecules. ABSTRACT 45 61 cytosolic domain structure_element Here crystallographic analyses of the PGRMC1 cytosolic domain at 1.95 Å resolution reveal that it forms a stable dimer through stacking interactions of two protruding haem molecules. ABSTRACT 106 112 stable protein_state Here crystallographic analyses of the PGRMC1 cytosolic domain at 1.95 Å resolution reveal that it forms a stable dimer through stacking interactions of two protruding haem molecules. ABSTRACT 113 118 dimer oligomeric_state Here crystallographic analyses of the PGRMC1 cytosolic domain at 1.95 Å resolution reveal that it forms a stable dimer through stacking interactions of two protruding haem molecules. ABSTRACT 127 148 stacking interactions bond_interaction Here crystallographic analyses of the PGRMC1 cytosolic domain at 1.95 Å resolution reveal that it forms a stable dimer through stacking interactions of two protruding haem molecules. ABSTRACT 167 171 haem chemical Here crystallographic analyses of the PGRMC1 cytosolic domain at 1.95 Å resolution reveal that it forms a stable dimer through stacking interactions of two protruding haem molecules. ABSTRACT 4 8 haem chemical The haem iron is five-coordinated by Tyr113, and the open surface of the haem mediates dimerization. ABSTRACT 9 13 iron chemical The haem iron is five-coordinated by Tyr113, and the open surface of the haem mediates dimerization. ABSTRACT 17 36 five-coordinated by bond_interaction The haem iron is five-coordinated by Tyr113, and the open surface of the haem mediates dimerization. ABSTRACT 37 43 Tyr113 residue_name_number The haem iron is five-coordinated by Tyr113, and the open surface of the haem mediates dimerization. ABSTRACT 58 65 surface site The haem iron is five-coordinated by Tyr113, and the open surface of the haem mediates dimerization. ABSTRACT 73 77 haem chemical The haem iron is five-coordinated by Tyr113, and the open surface of the haem mediates dimerization. ABSTRACT 87 99 dimerization oligomeric_state The haem iron is five-coordinated by Tyr113, and the open surface of the haem mediates dimerization. ABSTRACT 0 15 Carbon monoxide chemical Carbon monoxide (CO) interferes with PGRMC1 dimerization by binding to the sixth coordination site of the haem. ABSTRACT 17 19 CO chemical Carbon monoxide (CO) interferes with PGRMC1 dimerization by binding to the sixth coordination site of the haem. ABSTRACT 37 43 PGRMC1 protein Carbon monoxide (CO) interferes with PGRMC1 dimerization by binding to the sixth coordination site of the haem. ABSTRACT 44 56 dimerization oligomeric_state Carbon monoxide (CO) interferes with PGRMC1 dimerization by binding to the sixth coordination site of the haem. ABSTRACT 75 98 sixth coordination site site Carbon monoxide (CO) interferes with PGRMC1 dimerization by binding to the sixth coordination site of the haem. ABSTRACT 106 110 haem chemical Carbon monoxide (CO) interferes with PGRMC1 dimerization by binding to the sixth coordination site of the haem. ABSTRACT 0 4 Haem chemical Haem-mediated PGRMC1 dimerization is required for interactions with EGFR and cytochromes P450, cancer proliferation and chemoresistance against anti-cancer drugs; these events are attenuated by either CO or haem deprivation in cancer cells. ABSTRACT 14 20 PGRMC1 protein Haem-mediated PGRMC1 dimerization is required for interactions with EGFR and cytochromes P450, cancer proliferation and chemoresistance against anti-cancer drugs; these events are attenuated by either CO or haem deprivation in cancer cells. ABSTRACT 21 33 dimerization oligomeric_state Haem-mediated PGRMC1 dimerization is required for interactions with EGFR and cytochromes P450, cancer proliferation and chemoresistance against anti-cancer drugs; these events are attenuated by either CO or haem deprivation in cancer cells. ABSTRACT 68 72 EGFR protein_type Haem-mediated PGRMC1 dimerization is required for interactions with EGFR and cytochromes P450, cancer proliferation and chemoresistance against anti-cancer drugs; these events are attenuated by either CO or haem deprivation in cancer cells. ABSTRACT 77 93 cytochromes P450 protein_type Haem-mediated PGRMC1 dimerization is required for interactions with EGFR and cytochromes P450, cancer proliferation and chemoresistance against anti-cancer drugs; these events are attenuated by either CO or haem deprivation in cancer cells. ABSTRACT 201 203 CO chemical Haem-mediated PGRMC1 dimerization is required for interactions with EGFR and cytochromes P450, cancer proliferation and chemoresistance against anti-cancer drugs; these events are attenuated by either CO or haem deprivation in cancer cells. ABSTRACT 207 211 haem chemical Haem-mediated PGRMC1 dimerization is required for interactions with EGFR and cytochromes P450, cancer proliferation and chemoresistance against anti-cancer drugs; these events are attenuated by either CO or haem deprivation in cancer cells. ABSTRACT 32 44 dimerization oligomeric_state This study demonstrates protein dimerization via haem–haem stacking, which has not been seen in eukaryotes, and provides insights into its functional significance in cancer. ABSTRACT 49 67 haem–haem stacking bond_interaction This study demonstrates protein dimerization via haem–haem stacking, which has not been seen in eukaryotes, and provides insights into its functional significance in cancer. ABSTRACT 96 106 eukaryotes taxonomy_domain This study demonstrates protein dimerization via haem–haem stacking, which has not been seen in eukaryotes, and provides insights into its functional significance in cancer. ABSTRACT 1 7 PGRMC1 protein PGRMC1 binds to EGFR and cytochromes P450, and is known to be involved in cancer proliferation and in drug resistance. ABSTRACT 17 21 EGFR protein_type PGRMC1 binds to EGFR and cytochromes P450, and is known to be involved in cancer proliferation and in drug resistance. ABSTRACT 26 42 cytochromes P450 protein_type PGRMC1 binds to EGFR and cytochromes P450, and is known to be involved in cancer proliferation and in drug resistance. ABSTRACT 32 41 structure evidence Here, the authors determine the structure of the cytosolic domain of PGRMC1, which forms a dimer via haem–haem stacking, and propose how this interaction could be involved in its function. ABSTRACT 49 65 cytosolic domain structure_element Here, the authors determine the structure of the cytosolic domain of PGRMC1, which forms a dimer via haem–haem stacking, and propose how this interaction could be involved in its function. ABSTRACT 69 75 PGRMC1 protein Here, the authors determine the structure of the cytosolic domain of PGRMC1, which forms a dimer via haem–haem stacking, and propose how this interaction could be involved in its function. ABSTRACT 91 96 dimer oligomeric_state Here, the authors determine the structure of the cytosolic domain of PGRMC1, which forms a dimer via haem–haem stacking, and propose how this interaction could be involved in its function. ABSTRACT 101 119 haem–haem stacking bond_interaction Here, the authors determine the structure of the cytosolic domain of PGRMC1, which forms a dimer via haem–haem stacking, and propose how this interaction could be involved in its function. ABSTRACT 45 49 haem chemical Much attention has been paid to the roles of haem-iron in cancer development. INTRO 50 54 iron chemical Much attention has been paid to the roles of haem-iron in cancer development. INTRO 28 32 haem chemical Increased dietary intake of haem is a risk factor for several types of cancer. INTRO 29 43 deprivation of protein_state Previous studies showed that deprivation of iron or haem suppresses tumourigenesis. INTRO 44 48 iron chemical Previous studies showed that deprivation of iron or haem suppresses tumourigenesis. INTRO 52 56 haem chemical Previous studies showed that deprivation of iron or haem suppresses tumourigenesis. INTRO 19 34 carbon monoxide chemical On the other hand, carbon monoxide (CO), the gaseous mediator generated by oxidative degradation of haem via haem oxygenase (HO), inhibits tumour growth. INTRO 36 38 CO chemical On the other hand, carbon monoxide (CO), the gaseous mediator generated by oxidative degradation of haem via haem oxygenase (HO), inhibits tumour growth. INTRO 100 104 haem chemical On the other hand, carbon monoxide (CO), the gaseous mediator generated by oxidative degradation of haem via haem oxygenase (HO), inhibits tumour growth. INTRO 109 123 haem oxygenase protein_type On the other hand, carbon monoxide (CO), the gaseous mediator generated by oxidative degradation of haem via haem oxygenase (HO), inhibits tumour growth. INTRO 125 127 HO protein_type On the other hand, carbon monoxide (CO), the gaseous mediator generated by oxidative degradation of haem via haem oxygenase (HO), inhibits tumour growth. INTRO 37 41 haem chemical Thus, a tenuous balance between free haem and CO plays key roles in cancer development and chemoresistance, although the underlying mechanisms are not fully understood. INTRO 46 48 CO chemical Thus, a tenuous balance between free haem and CO plays key roles in cancer development and chemoresistance, although the underlying mechanisms are not fully understood. INTRO 93 111 affinity nanobeads experimental_method To gain insight into the underlying mechanisms, we took chemical biological approaches using affinity nanobeads carrying haem and identified progesterone-receptor membrane component 1 (PGRMC1) as a haem-binding protein from mouse liver extracts (Supplementary Fig. 1). INTRO 121 125 haem chemical To gain insight into the underlying mechanisms, we took chemical biological approaches using affinity nanobeads carrying haem and identified progesterone-receptor membrane component 1 (PGRMC1) as a haem-binding protein from mouse liver extracts (Supplementary Fig. 1). INTRO 141 183 progesterone-receptor membrane component 1 protein To gain insight into the underlying mechanisms, we took chemical biological approaches using affinity nanobeads carrying haem and identified progesterone-receptor membrane component 1 (PGRMC1) as a haem-binding protein from mouse liver extracts (Supplementary Fig. 1). INTRO 185 191 PGRMC1 protein To gain insight into the underlying mechanisms, we took chemical biological approaches using affinity nanobeads carrying haem and identified progesterone-receptor membrane component 1 (PGRMC1) as a haem-binding protein from mouse liver extracts (Supplementary Fig. 1). INTRO 198 202 haem chemical To gain insight into the underlying mechanisms, we took chemical biological approaches using affinity nanobeads carrying haem and identified progesterone-receptor membrane component 1 (PGRMC1) as a haem-binding protein from mouse liver extracts (Supplementary Fig. 1). INTRO 224 229 mouse taxonomy_domain To gain insight into the underlying mechanisms, we took chemical biological approaches using affinity nanobeads carrying haem and identified progesterone-receptor membrane component 1 (PGRMC1) as a haem-binding protein from mouse liver extracts (Supplementary Fig. 1). INTRO 0 6 PGRMC1 protein PGRMC1 is a member of the membrane-associated progesterone receptor (MAPR) family with a cytochrome b5-like haem-binding region, and is known to be highly expressed in various types of cancers. INTRO 26 67 membrane-associated progesterone receptor protein_type PGRMC1 is a member of the membrane-associated progesterone receptor (MAPR) family with a cytochrome b5-like haem-binding region, and is known to be highly expressed in various types of cancers. INTRO 69 73 MAPR protein_type PGRMC1 is a member of the membrane-associated progesterone receptor (MAPR) family with a cytochrome b5-like haem-binding region, and is known to be highly expressed in various types of cancers. INTRO 89 107 cytochrome b5-like structure_element PGRMC1 is a member of the membrane-associated progesterone receptor (MAPR) family with a cytochrome b5-like haem-binding region, and is known to be highly expressed in various types of cancers. INTRO 108 127 haem-binding region site PGRMC1 is a member of the membrane-associated progesterone receptor (MAPR) family with a cytochrome b5-like haem-binding region, and is known to be highly expressed in various types of cancers. INTRO 148 164 highly expressed protein_state PGRMC1 is a member of the membrane-associated progesterone receptor (MAPR) family with a cytochrome b5-like haem-binding region, and is known to be highly expressed in various types of cancers. INTRO 0 6 PGRMC1 protein PGRMC1 is anchored to the cell membrane through the N-terminal transmembrane helix and interacts with epidermal growth factor receptor (EGFR) and cytochromes P450 (ref). INTRO 63 82 transmembrane helix structure_element PGRMC1 is anchored to the cell membrane through the N-terminal transmembrane helix and interacts with epidermal growth factor receptor (EGFR) and cytochromes P450 (ref). INTRO 102 134 epidermal growth factor receptor protein_type PGRMC1 is anchored to the cell membrane through the N-terminal transmembrane helix and interacts with epidermal growth factor receptor (EGFR) and cytochromes P450 (ref). INTRO 136 140 EGFR protein_type PGRMC1 is anchored to the cell membrane through the N-terminal transmembrane helix and interacts with epidermal growth factor receptor (EGFR) and cytochromes P450 (ref). INTRO 146 162 cytochromes P450 protein_type PGRMC1 is anchored to the cell membrane through the N-terminal transmembrane helix and interacts with epidermal growth factor receptor (EGFR) and cytochromes P450 (ref). INTRO 6 12 PGRMC1 protein While PGRMC1 is implicated in cell proliferation and cholesterol biosynthesis, the structural basis on which PGRMC1 exerts its function remains largely unknown. INTRO 109 115 PGRMC1 protein While PGRMC1 is implicated in cell proliferation and cholesterol biosynthesis, the structural basis on which PGRMC1 exerts its function remains largely unknown. INTRO 18 24 PGRMC1 protein Here we show that PGRMC1 exhibits a unique haem-dependent dimerization. INTRO 43 47 haem chemical Here we show that PGRMC1 exhibits a unique haem-dependent dimerization. INTRO 58 70 dimerization oligomeric_state Here we show that PGRMC1 exhibits a unique haem-dependent dimerization. INTRO 4 9 dimer oligomeric_state The dimer binds to EGFR and cytochromes P450 to enhance tumour cell proliferation and chemoresistance. INTRO 19 23 EGFR protein_type The dimer binds to EGFR and cytochromes P450 to enhance tumour cell proliferation and chemoresistance. INTRO 28 44 cytochromes P450 protein_type The dimer binds to EGFR and cytochromes P450 to enhance tumour cell proliferation and chemoresistance. INTRO 4 9 dimer oligomeric_state The dimer is dissociated to monomers by physiological levels of CO, suggesting that PGRMC1 serves as a CO-sensitive molecular switch regulating cancer cell proliferation. INTRO 28 36 monomers oligomeric_state The dimer is dissociated to monomers by physiological levels of CO, suggesting that PGRMC1 serves as a CO-sensitive molecular switch regulating cancer cell proliferation. INTRO 64 66 CO chemical The dimer is dissociated to monomers by physiological levels of CO, suggesting that PGRMC1 serves as a CO-sensitive molecular switch regulating cancer cell proliferation. INTRO 84 90 PGRMC1 protein The dimer is dissociated to monomers by physiological levels of CO, suggesting that PGRMC1 serves as a CO-sensitive molecular switch regulating cancer cell proliferation. INTRO 103 105 CO chemical The dimer is dissociated to monomers by physiological levels of CO, suggesting that PGRMC1 serves as a CO-sensitive molecular switch regulating cancer cell proliferation. INTRO 0 23 X-ray crystal structure evidence X-ray crystal structure of PGRMC1 RESULTS 27 33 PGRMC1 protein X-ray crystal structure of PGRMC1 RESULTS 3 9 solved experimental_method We solved the crystal structure of the haem-bound PGRMC1 cytosolic domain (a.a.72–195) at 1.95 Å resolution (Supplementary Fig. 2). RESULTS 14 31 crystal structure evidence We solved the crystal structure of the haem-bound PGRMC1 cytosolic domain (a.a.72–195) at 1.95 Å resolution (Supplementary Fig. 2). RESULTS 39 49 haem-bound protein_state We solved the crystal structure of the haem-bound PGRMC1 cytosolic domain (a.a.72–195) at 1.95 Å resolution (Supplementary Fig. 2). RESULTS 50 56 PGRMC1 protein We solved the crystal structure of the haem-bound PGRMC1 cytosolic domain (a.a.72–195) at 1.95 Å resolution (Supplementary Fig. 2). RESULTS 57 73 cytosolic domain structure_element We solved the crystal structure of the haem-bound PGRMC1 cytosolic domain (a.a.72–195) at 1.95 Å resolution (Supplementary Fig. 2). RESULTS 79 85 72–195 residue_range We solved the crystal structure of the haem-bound PGRMC1 cytosolic domain (a.a.72–195) at 1.95 Å resolution (Supplementary Fig. 2). RESULTS 7 18 presence of protein_state In the presence of haem, PGRMC1 forms a dimeric structure largely through hydrophobic interactions between the haem moieties of two monomers (Fig. 1a, Table 1 and Supplementary Fig. 3; a stereo-structural image is shown in Supplementary Fig 4). RESULTS 19 23 haem chemical In the presence of haem, PGRMC1 forms a dimeric structure largely through hydrophobic interactions between the haem moieties of two monomers (Fig. 1a, Table 1 and Supplementary Fig. 3; a stereo-structural image is shown in Supplementary Fig 4). RESULTS 25 31 PGRMC1 protein In the presence of haem, PGRMC1 forms a dimeric structure largely through hydrophobic interactions between the haem moieties of two monomers (Fig. 1a, Table 1 and Supplementary Fig. 3; a stereo-structural image is shown in Supplementary Fig 4). RESULTS 40 47 dimeric oligomeric_state In the presence of haem, PGRMC1 forms a dimeric structure largely through hydrophobic interactions between the haem moieties of two monomers (Fig. 1a, Table 1 and Supplementary Fig. 3; a stereo-structural image is shown in Supplementary Fig 4). RESULTS 74 98 hydrophobic interactions bond_interaction In the presence of haem, PGRMC1 forms a dimeric structure largely through hydrophobic interactions between the haem moieties of two monomers (Fig. 1a, Table 1 and Supplementary Fig. 3; a stereo-structural image is shown in Supplementary Fig 4). RESULTS 111 115 haem chemical In the presence of haem, PGRMC1 forms a dimeric structure largely through hydrophobic interactions between the haem moieties of two monomers (Fig. 1a, Table 1 and Supplementary Fig. 3; a stereo-structural image is shown in Supplementary Fig 4). RESULTS 132 140 monomers oligomeric_state In the presence of haem, PGRMC1 forms a dimeric structure largely through hydrophobic interactions between the haem moieties of two monomers (Fig. 1a, Table 1 and Supplementary Fig. 3; a stereo-structural image is shown in Supplementary Fig 4). RESULTS 26 32 PGRMC1 protein While the overall fold of PGRMC1 is similar to that of canonical cytochrome b5, their haem irons are coordinated differently. RESULTS 65 78 cytochrome b5 protein_type While the overall fold of PGRMC1 is similar to that of canonical cytochrome b5, their haem irons are coordinated differently. RESULTS 86 90 haem chemical While the overall fold of PGRMC1 is similar to that of canonical cytochrome b5, their haem irons are coordinated differently. RESULTS 3 16 cytochrome b5 protein_type In cytochrome b5, the haem iron is six-coordinated by two axial histidine residues. RESULTS 22 26 haem chemical In cytochrome b5, the haem iron is six-coordinated by two axial histidine residues. RESULTS 27 31 iron chemical In cytochrome b5, the haem iron is six-coordinated by two axial histidine residues. RESULTS 35 53 six-coordinated by bond_interaction In cytochrome b5, the haem iron is six-coordinated by two axial histidine residues. RESULTS 64 73 histidine residue_name In cytochrome b5, the haem iron is six-coordinated by two axial histidine residues. RESULTS 6 16 histidines residue_name These histidines are missing in PGRMC1, and the haem iron is five-coordinated by Tyr113 (Y113) alone (Fig. 1b and Supplementary Fig. 3). RESULTS 21 28 missing protein_state These histidines are missing in PGRMC1, and the haem iron is five-coordinated by Tyr113 (Y113) alone (Fig. 1b and Supplementary Fig. 3). RESULTS 32 38 PGRMC1 protein These histidines are missing in PGRMC1, and the haem iron is five-coordinated by Tyr113 (Y113) alone (Fig. 1b and Supplementary Fig. 3). RESULTS 48 52 haem chemical These histidines are missing in PGRMC1, and the haem iron is five-coordinated by Tyr113 (Y113) alone (Fig. 1b and Supplementary Fig. 3). RESULTS 53 57 iron chemical These histidines are missing in PGRMC1, and the haem iron is five-coordinated by Tyr113 (Y113) alone (Fig. 1b and Supplementary Fig. 3). RESULTS 61 80 five-coordinated by bond_interaction These histidines are missing in PGRMC1, and the haem iron is five-coordinated by Tyr113 (Y113) alone (Fig. 1b and Supplementary Fig. 3). RESULTS 81 87 Tyr113 residue_name_number These histidines are missing in PGRMC1, and the haem iron is five-coordinated by Tyr113 (Y113) alone (Fig. 1b and Supplementary Fig. 3). RESULTS 89 93 Y113 residue_name_number These histidines are missing in PGRMC1, and the haem iron is five-coordinated by Tyr113 (Y113) alone (Fig. 1b and Supplementary Fig. 3). RESULTS 95 100 alone protein_state These histidines are missing in PGRMC1, and the haem iron is five-coordinated by Tyr113 (Y113) alone (Fig. 1b and Supplementary Fig. 3). RESULTS 2 18 homologous helix structure_element A homologous helix that holds haem in cytochrome b5 is longer, shifts away from haem, and does not form a coordinate bond in PGRMC1 (Fig. 1c). RESULTS 30 34 haem chemical A homologous helix that holds haem in cytochrome b5 is longer, shifts away from haem, and does not form a coordinate bond in PGRMC1 (Fig. 1c). RESULTS 38 51 cytochrome b5 protein_type A homologous helix that holds haem in cytochrome b5 is longer, shifts away from haem, and does not form a coordinate bond in PGRMC1 (Fig. 1c). RESULTS 80 84 haem chemical A homologous helix that holds haem in cytochrome b5 is longer, shifts away from haem, and does not form a coordinate bond in PGRMC1 (Fig. 1c). RESULTS 125 131 PGRMC1 protein A homologous helix that holds haem in cytochrome b5 is longer, shifts away from haem, and does not form a coordinate bond in PGRMC1 (Fig. 1c). RESULTS 35 39 haem chemical Consequently, the five-coordinated haem of PGRMC1 has an open surface that allows its dimerization through hydrophobic haem–haem stacking. RESULTS 43 49 PGRMC1 protein Consequently, the five-coordinated haem of PGRMC1 has an open surface that allows its dimerization through hydrophobic haem–haem stacking. RESULTS 62 69 surface site Consequently, the five-coordinated haem of PGRMC1 has an open surface that allows its dimerization through hydrophobic haem–haem stacking. RESULTS 86 98 dimerization oligomeric_state Consequently, the five-coordinated haem of PGRMC1 has an open surface that allows its dimerization through hydrophobic haem–haem stacking. RESULTS 107 137 hydrophobic haem–haem stacking bond_interaction Consequently, the five-coordinated haem of PGRMC1 has an open surface that allows its dimerization through hydrophobic haem–haem stacking. RESULTS 62 68 Tyr164 residue_name_number Contrary to our finding, Kaluka et al. recently reported that Tyr164 of PGRMC1 is the axial ligand of haem because mutation of this residue impairs haem binding. RESULTS 72 78 PGRMC1 protein Contrary to our finding, Kaluka et al. recently reported that Tyr164 of PGRMC1 is the axial ligand of haem because mutation of this residue impairs haem binding. RESULTS 102 106 haem chemical Contrary to our finding, Kaluka et al. recently reported that Tyr164 of PGRMC1 is the axial ligand of haem because mutation of this residue impairs haem binding. RESULTS 115 123 mutation experimental_method Contrary to our finding, Kaluka et al. recently reported that Tyr164 of PGRMC1 is the axial ligand of haem because mutation of this residue impairs haem binding. RESULTS 148 152 haem chemical Contrary to our finding, Kaluka et al. recently reported that Tyr164 of PGRMC1 is the axial ligand of haem because mutation of this residue impairs haem binding. RESULTS 4 19 structural data evidence Our structural data revealed that Tyr164 and a few other residues such as Tyr107 and Lys163 are in fact hydrogen-bonded to haem propionates. RESULTS 34 40 Tyr164 residue_name_number Our structural data revealed that Tyr164 and a few other residues such as Tyr107 and Lys163 are in fact hydrogen-bonded to haem propionates. RESULTS 74 80 Tyr107 residue_name_number Our structural data revealed that Tyr164 and a few other residues such as Tyr107 and Lys163 are in fact hydrogen-bonded to haem propionates. RESULTS 85 91 Lys163 residue_name_number Our structural data revealed that Tyr164 and a few other residues such as Tyr107 and Lys163 are in fact hydrogen-bonded to haem propionates. RESULTS 104 119 hydrogen-bonded bond_interaction Our structural data revealed that Tyr164 and a few other residues such as Tyr107 and Lys163 are in fact hydrogen-bonded to haem propionates. RESULTS 123 127 haem chemical Our structural data revealed that Tyr164 and a few other residues such as Tyr107 and Lys163 are in fact hydrogen-bonded to haem propionates. RESULTS 56 63 Tyr 107 residue_name_number This is consistent with observations by Min et al. that Tyr 107 and Tyr113 of PGRMC1 are involved in binding with haem. RESULTS 68 74 Tyr113 residue_name_number This is consistent with observations by Min et al. that Tyr 107 and Tyr113 of PGRMC1 are involved in binding with haem. RESULTS 78 84 PGRMC1 protein This is consistent with observations by Min et al. that Tyr 107 and Tyr113 of PGRMC1 are involved in binding with haem. RESULTS 114 118 haem chemical This is consistent with observations by Min et al. that Tyr 107 and Tyr113 of PGRMC1 are involved in binding with haem. RESULTS 30 39 conserved protein_state These amino acid residues are conserved among MAPR family members (Supplementary Fig. 5a), suggesting that these proteins share the ability to exhibit haem-dependent dimerization. RESULTS 46 50 MAPR protein_type These amino acid residues are conserved among MAPR family members (Supplementary Fig. 5a), suggesting that these proteins share the ability to exhibit haem-dependent dimerization. RESULTS 151 155 haem chemical These amino acid residues are conserved among MAPR family members (Supplementary Fig. 5a), suggesting that these proteins share the ability to exhibit haem-dependent dimerization. RESULTS 166 178 dimerization oligomeric_state These amino acid residues are conserved among MAPR family members (Supplementary Fig. 5a), suggesting that these proteins share the ability to exhibit haem-dependent dimerization. RESULTS 0 6 PGRMC1 protein PGRMC1 exhibits haem-dependent dimerization in solution RESULTS 16 20 haem chemical PGRMC1 exhibits haem-dependent dimerization in solution RESULTS 31 43 dimerization oligomeric_state PGRMC1 exhibits haem-dependent dimerization in solution RESULTS 7 13 PGRMC1 protein In the PGRMC1 crystal, two different types of crystal contacts (chain A–A″ and A–B) were observed in addition to the haem-mediated dimer (chain A–A′) (Supplementary Figs 3 and 6a). RESULTS 14 21 crystal evidence In the PGRMC1 crystal, two different types of crystal contacts (chain A–A″ and A–B) were observed in addition to the haem-mediated dimer (chain A–A′) (Supplementary Figs 3 and 6a). RESULTS 117 121 haem chemical In the PGRMC1 crystal, two different types of crystal contacts (chain A–A″ and A–B) were observed in addition to the haem-mediated dimer (chain A–A′) (Supplementary Figs 3 and 6a). RESULTS 131 136 dimer oligomeric_state In the PGRMC1 crystal, two different types of crystal contacts (chain A–A″ and A–B) were observed in addition to the haem-mediated dimer (chain A–A′) (Supplementary Figs 3 and 6a). RESULTS 16 20 haem chemical To confirm that haem-assisted dimerization of PGRMC1 occurs in solution, we analysed the structure of apo- and haem-bound PGMRC1 by two-dimensional nuclear magnetic resonance (NMR) using heteronuclear single-quantum coherence and transverse relaxation-optimized spectroscopy (Supplementary Figs 6b and 7). RESULTS 30 42 dimerization oligomeric_state To confirm that haem-assisted dimerization of PGRMC1 occurs in solution, we analysed the structure of apo- and haem-bound PGMRC1 by two-dimensional nuclear magnetic resonance (NMR) using heteronuclear single-quantum coherence and transverse relaxation-optimized spectroscopy (Supplementary Figs 6b and 7). RESULTS 46 52 PGRMC1 protein To confirm that haem-assisted dimerization of PGRMC1 occurs in solution, we analysed the structure of apo- and haem-bound PGMRC1 by two-dimensional nuclear magnetic resonance (NMR) using heteronuclear single-quantum coherence and transverse relaxation-optimized spectroscopy (Supplementary Figs 6b and 7). RESULTS 89 98 structure evidence To confirm that haem-assisted dimerization of PGRMC1 occurs in solution, we analysed the structure of apo- and haem-bound PGMRC1 by two-dimensional nuclear magnetic resonance (NMR) using heteronuclear single-quantum coherence and transverse relaxation-optimized spectroscopy (Supplementary Figs 6b and 7). RESULTS 102 105 apo protein_state To confirm that haem-assisted dimerization of PGRMC1 occurs in solution, we analysed the structure of apo- and haem-bound PGMRC1 by two-dimensional nuclear magnetic resonance (NMR) using heteronuclear single-quantum coherence and transverse relaxation-optimized spectroscopy (Supplementary Figs 6b and 7). RESULTS 111 121 haem-bound protein_state To confirm that haem-assisted dimerization of PGRMC1 occurs in solution, we analysed the structure of apo- and haem-bound PGMRC1 by two-dimensional nuclear magnetic resonance (NMR) using heteronuclear single-quantum coherence and transverse relaxation-optimized spectroscopy (Supplementary Figs 6b and 7). RESULTS 122 128 PGMRC1 protein To confirm that haem-assisted dimerization of PGRMC1 occurs in solution, we analysed the structure of apo- and haem-bound PGMRC1 by two-dimensional nuclear magnetic resonance (NMR) using heteronuclear single-quantum coherence and transverse relaxation-optimized spectroscopy (Supplementary Figs 6b and 7). RESULTS 132 174 two-dimensional nuclear magnetic resonance experimental_method To confirm that haem-assisted dimerization of PGRMC1 occurs in solution, we analysed the structure of apo- and haem-bound PGMRC1 by two-dimensional nuclear magnetic resonance (NMR) using heteronuclear single-quantum coherence and transverse relaxation-optimized spectroscopy (Supplementary Figs 6b and 7). RESULTS 176 179 NMR experimental_method To confirm that haem-assisted dimerization of PGRMC1 occurs in solution, we analysed the structure of apo- and haem-bound PGMRC1 by two-dimensional nuclear magnetic resonance (NMR) using heteronuclear single-quantum coherence and transverse relaxation-optimized spectroscopy (Supplementary Figs 6b and 7). RESULTS 187 274 heteronuclear single-quantum coherence and transverse relaxation-optimized spectroscopy experimental_method To confirm that haem-assisted dimerization of PGRMC1 occurs in solution, we analysed the structure of apo- and haem-bound PGMRC1 by two-dimensional nuclear magnetic resonance (NMR) using heteronuclear single-quantum coherence and transverse relaxation-optimized spectroscopy (Supplementary Figs 6b and 7). RESULTS 0 3 NMR experimental_method NMR signals from some amino acid residues of PGRMC1 disappeared due to the paramagnetic relaxation effect of haem (Supplementary Figs 6b); these residues were located in the haem-binding region. RESULTS 45 51 PGRMC1 protein NMR signals from some amino acid residues of PGRMC1 disappeared due to the paramagnetic relaxation effect of haem (Supplementary Figs 6b); these residues were located in the haem-binding region. RESULTS 109 113 haem chemical NMR signals from some amino acid residues of PGRMC1 disappeared due to the paramagnetic relaxation effect of haem (Supplementary Figs 6b); these residues were located in the haem-binding region. RESULTS 174 193 haem-binding region site NMR signals from some amino acid residues of PGRMC1 disappeared due to the paramagnetic relaxation effect of haem (Supplementary Figs 6b); these residues were located in the haem-binding region. RESULTS 5 20 chemical shifts evidence When chemical shifts of apo- and haem-bound forms of PGMRC1 were compared, some amino acid residues close to those which disappeared because of the paramagnetic relaxation effect of haem exhibit notable chemical shifts (Supplementary Fig. 6a,b; dark yellow). RESULTS 24 27 apo protein_state When chemical shifts of apo- and haem-bound forms of PGMRC1 were compared, some amino acid residues close to those which disappeared because of the paramagnetic relaxation effect of haem exhibit notable chemical shifts (Supplementary Fig. 6a,b; dark yellow). RESULTS 33 43 haem-bound protein_state When chemical shifts of apo- and haem-bound forms of PGMRC1 were compared, some amino acid residues close to those which disappeared because of the paramagnetic relaxation effect of haem exhibit notable chemical shifts (Supplementary Fig. 6a,b; dark yellow). RESULTS 53 59 PGMRC1 protein When chemical shifts of apo- and haem-bound forms of PGMRC1 were compared, some amino acid residues close to those which disappeared because of the paramagnetic relaxation effect of haem exhibit notable chemical shifts (Supplementary Fig. 6a,b; dark yellow). RESULTS 182 186 haem chemical When chemical shifts of apo- and haem-bound forms of PGMRC1 were compared, some amino acid residues close to those which disappeared because of the paramagnetic relaxation effect of haem exhibit notable chemical shifts (Supplementary Fig. 6a,b; dark yellow). RESULTS 16 26 interfaces site However, at the interfaces of the other possible dimeric structures (Supplementary Fig. 6a, chain A–A″; cyan and chain A–B; violet), no significant difference was observed. RESULTS 49 56 dimeric oligomeric_state However, at the interfaces of the other possible dimeric structures (Supplementary Fig. 6a, chain A–A″; cyan and chain A–B; violet), no significant difference was observed. RESULTS 57 67 structures evidence However, at the interfaces of the other possible dimeric structures (Supplementary Fig. 6a, chain A–A″; cyan and chain A–B; violet), no significant difference was observed. RESULTS 13 40 free energy of dissociation evidence Furthermore, free energy of dissociation predicted by PISA suggested that the haem-mediated dimer is stable in solution while the other potential interactions are not. RESULTS 54 58 PISA experimental_method Furthermore, free energy of dissociation predicted by PISA suggested that the haem-mediated dimer is stable in solution while the other potential interactions are not. RESULTS 78 82 haem chemical Furthermore, free energy of dissociation predicted by PISA suggested that the haem-mediated dimer is stable in solution while the other potential interactions are not. RESULTS 92 97 dimer oligomeric_state Furthermore, free energy of dissociation predicted by PISA suggested that the haem-mediated dimer is stable in solution while the other potential interactions are not. RESULTS 101 107 stable protein_state Furthermore, free energy of dissociation predicted by PISA suggested that the haem-mediated dimer is stable in solution while the other potential interactions are not. RESULTS 56 62 PGRMC1 protein We also attempted to predict the secondary structure of PGRMC1 through NMR data by calculating with TALOS+ program (Supplementary Fig. 8); the prediction suggested that the overall secondary structure is comparable between apo- and haem-bound forms of PGRMC1 in solution. RESULTS 71 74 NMR experimental_method We also attempted to predict the secondary structure of PGRMC1 through NMR data by calculating with TALOS+ program (Supplementary Fig. 8); the prediction suggested that the overall secondary structure is comparable between apo- and haem-bound forms of PGRMC1 in solution. RESULTS 100 114 TALOS+ program experimental_method We also attempted to predict the secondary structure of PGRMC1 through NMR data by calculating with TALOS+ program (Supplementary Fig. 8); the prediction suggested that the overall secondary structure is comparable between apo- and haem-bound forms of PGRMC1 in solution. RESULTS 223 226 apo protein_state We also attempted to predict the secondary structure of PGRMC1 through NMR data by calculating with TALOS+ program (Supplementary Fig. 8); the prediction suggested that the overall secondary structure is comparable between apo- and haem-bound forms of PGRMC1 in solution. RESULTS 232 242 haem-bound protein_state We also attempted to predict the secondary structure of PGRMC1 through NMR data by calculating with TALOS+ program (Supplementary Fig. 8); the prediction suggested that the overall secondary structure is comparable between apo- and haem-bound forms of PGRMC1 in solution. RESULTS 252 258 PGRMC1 protein We also attempted to predict the secondary structure of PGRMC1 through NMR data by calculating with TALOS+ program (Supplementary Fig. 8); the prediction suggested that the overall secondary structure is comparable between apo- and haem-bound forms of PGRMC1 in solution. RESULTS 16 20 haem chemical We analysed the haem-dependent dimerization of the PGRMC1 cytosolic domain (a.a.44–195) in solution (Fig. 2 and Table 2). RESULTS 31 43 dimerization oligomeric_state We analysed the haem-dependent dimerization of the PGRMC1 cytosolic domain (a.a.44–195) in solution (Fig. 2 and Table 2). RESULTS 51 57 PGRMC1 protein We analysed the haem-dependent dimerization of the PGRMC1 cytosolic domain (a.a.44–195) in solution (Fig. 2 and Table 2). RESULTS 58 74 cytosolic domain structure_element We analysed the haem-dependent dimerization of the PGRMC1 cytosolic domain (a.a.44–195) in solution (Fig. 2 and Table 2). RESULTS 80 86 44–195 residue_range We analysed the haem-dependent dimerization of the PGRMC1 cytosolic domain (a.a.44–195) in solution (Fig. 2 and Table 2). RESULTS 0 17 Mass spectrometry experimental_method Mass spectrometry (MS) analyses under non-denaturing condition demonstrated that the apo-monomer PGRMC1 resulted in dimerization by binding with haem (Fig. 2a). RESULTS 19 21 MS experimental_method Mass spectrometry (MS) analyses under non-denaturing condition demonstrated that the apo-monomer PGRMC1 resulted in dimerization by binding with haem (Fig. 2a). RESULTS 38 62 non-denaturing condition experimental_method Mass spectrometry (MS) analyses under non-denaturing condition demonstrated that the apo-monomer PGRMC1 resulted in dimerization by binding with haem (Fig. 2a). RESULTS 85 88 apo protein_state Mass spectrometry (MS) analyses under non-denaturing condition demonstrated that the apo-monomer PGRMC1 resulted in dimerization by binding with haem (Fig. 2a). RESULTS 89 96 monomer oligomeric_state Mass spectrometry (MS) analyses under non-denaturing condition demonstrated that the apo-monomer PGRMC1 resulted in dimerization by binding with haem (Fig. 2a). RESULTS 97 103 PGRMC1 protein Mass spectrometry (MS) analyses under non-denaturing condition demonstrated that the apo-monomer PGRMC1 resulted in dimerization by binding with haem (Fig. 2a). RESULTS 116 128 dimerization oligomeric_state Mass spectrometry (MS) analyses under non-denaturing condition demonstrated that the apo-monomer PGRMC1 resulted in dimerization by binding with haem (Fig. 2a). RESULTS 145 149 haem chemical Mass spectrometry (MS) analyses under non-denaturing condition demonstrated that the apo-monomer PGRMC1 resulted in dimerization by binding with haem (Fig. 2a). RESULTS 26 40 disulfide bond ptm It should be noted that a disulfide bond between two Cys129 residues is observed in the crystal of PGRMC1 (Fig. 1a), while Cys129 is not conserved among the MAPR family proteins (Supplementary Fig. 5a). RESULTS 53 59 Cys129 residue_name_number It should be noted that a disulfide bond between two Cys129 residues is observed in the crystal of PGRMC1 (Fig. 1a), while Cys129 is not conserved among the MAPR family proteins (Supplementary Fig. 5a). RESULTS 88 95 crystal evidence It should be noted that a disulfide bond between two Cys129 residues is observed in the crystal of PGRMC1 (Fig. 1a), while Cys129 is not conserved among the MAPR family proteins (Supplementary Fig. 5a). RESULTS 99 105 PGRMC1 protein It should be noted that a disulfide bond between two Cys129 residues is observed in the crystal of PGRMC1 (Fig. 1a), while Cys129 is not conserved among the MAPR family proteins (Supplementary Fig. 5a). RESULTS 123 129 Cys129 residue_name_number It should be noted that a disulfide bond between two Cys129 residues is observed in the crystal of PGRMC1 (Fig. 1a), while Cys129 is not conserved among the MAPR family proteins (Supplementary Fig. 5a). RESULTS 133 146 not conserved protein_state It should be noted that a disulfide bond between two Cys129 residues is observed in the crystal of PGRMC1 (Fig. 1a), while Cys129 is not conserved among the MAPR family proteins (Supplementary Fig. 5a). RESULTS 157 161 MAPR protein_type It should be noted that a disulfide bond between two Cys129 residues is observed in the crystal of PGRMC1 (Fig. 1a), while Cys129 is not conserved among the MAPR family proteins (Supplementary Fig. 5a). RESULTS 54 68 disulfide bond ptm This observation led us to examine whether or not the disulfide bond contributes to PGRMC1 dimerization. RESULTS 84 90 PGRMC1 protein This observation led us to examine whether or not the disulfide bond contributes to PGRMC1 dimerization. RESULTS 91 103 dimerization oligomeric_state This observation led us to examine whether or not the disulfide bond contributes to PGRMC1 dimerization. RESULTS 0 2 MS experimental_method MS analyses under non-denaturing conditions clearly showed that the Cys129Ser (C129S) mutant is dimerized in the presence of haem, indicating that the haem-mediated dimerization of PGRMC1 occurs independently of the disulfide bond formation via Cys129 (Fig. 2a). RESULTS 18 43 non-denaturing conditions experimental_method MS analyses under non-denaturing conditions clearly showed that the Cys129Ser (C129S) mutant is dimerized in the presence of haem, indicating that the haem-mediated dimerization of PGRMC1 occurs independently of the disulfide bond formation via Cys129 (Fig. 2a). RESULTS 68 77 Cys129Ser mutant MS analyses under non-denaturing conditions clearly showed that the Cys129Ser (C129S) mutant is dimerized in the presence of haem, indicating that the haem-mediated dimerization of PGRMC1 occurs independently of the disulfide bond formation via Cys129 (Fig. 2a). RESULTS 79 84 C129S mutant MS analyses under non-denaturing conditions clearly showed that the Cys129Ser (C129S) mutant is dimerized in the presence of haem, indicating that the haem-mediated dimerization of PGRMC1 occurs independently of the disulfide bond formation via Cys129 (Fig. 2a). RESULTS 86 92 mutant protein_state MS analyses under non-denaturing conditions clearly showed that the Cys129Ser (C129S) mutant is dimerized in the presence of haem, indicating that the haem-mediated dimerization of PGRMC1 occurs independently of the disulfide bond formation via Cys129 (Fig. 2a). RESULTS 96 105 dimerized protein_state MS analyses under non-denaturing conditions clearly showed that the Cys129Ser (C129S) mutant is dimerized in the presence of haem, indicating that the haem-mediated dimerization of PGRMC1 occurs independently of the disulfide bond formation via Cys129 (Fig. 2a). RESULTS 113 124 presence of protein_state MS analyses under non-denaturing conditions clearly showed that the Cys129Ser (C129S) mutant is dimerized in the presence of haem, indicating that the haem-mediated dimerization of PGRMC1 occurs independently of the disulfide bond formation via Cys129 (Fig. 2a). RESULTS 125 129 haem chemical MS analyses under non-denaturing conditions clearly showed that the Cys129Ser (C129S) mutant is dimerized in the presence of haem, indicating that the haem-mediated dimerization of PGRMC1 occurs independently of the disulfide bond formation via Cys129 (Fig. 2a). RESULTS 151 155 haem chemical MS analyses under non-denaturing conditions clearly showed that the Cys129Ser (C129S) mutant is dimerized in the presence of haem, indicating that the haem-mediated dimerization of PGRMC1 occurs independently of the disulfide bond formation via Cys129 (Fig. 2a). RESULTS 165 177 dimerization oligomeric_state MS analyses under non-denaturing conditions clearly showed that the Cys129Ser (C129S) mutant is dimerized in the presence of haem, indicating that the haem-mediated dimerization of PGRMC1 occurs independently of the disulfide bond formation via Cys129 (Fig. 2a). RESULTS 181 187 PGRMC1 protein MS analyses under non-denaturing conditions clearly showed that the Cys129Ser (C129S) mutant is dimerized in the presence of haem, indicating that the haem-mediated dimerization of PGRMC1 occurs independently of the disulfide bond formation via Cys129 (Fig. 2a). RESULTS 216 230 disulfide bond ptm MS analyses under non-denaturing conditions clearly showed that the Cys129Ser (C129S) mutant is dimerized in the presence of haem, indicating that the haem-mediated dimerization of PGRMC1 occurs independently of the disulfide bond formation via Cys129 (Fig. 2a). RESULTS 245 251 Cys129 residue_name_number MS analyses under non-denaturing conditions clearly showed that the Cys129Ser (C129S) mutant is dimerized in the presence of haem, indicating that the haem-mediated dimerization of PGRMC1 occurs independently of the disulfide bond formation via Cys129 (Fig. 2a). RESULTS 17 19 MS experimental_method Supporting this, MS analyses under denaturing conditions showed that haem-mediated PGRMC1 dimer is completely dissociated into monomer, indicating that dimerization of this kind is not mediated by any covalent bond such as disulfide bond (Supplementary Fig. 9). RESULTS 35 56 denaturing conditions experimental_method Supporting this, MS analyses under denaturing conditions showed that haem-mediated PGRMC1 dimer is completely dissociated into monomer, indicating that dimerization of this kind is not mediated by any covalent bond such as disulfide bond (Supplementary Fig. 9). RESULTS 69 73 haem chemical Supporting this, MS analyses under denaturing conditions showed that haem-mediated PGRMC1 dimer is completely dissociated into monomer, indicating that dimerization of this kind is not mediated by any covalent bond such as disulfide bond (Supplementary Fig. 9). RESULTS 83 89 PGRMC1 protein Supporting this, MS analyses under denaturing conditions showed that haem-mediated PGRMC1 dimer is completely dissociated into monomer, indicating that dimerization of this kind is not mediated by any covalent bond such as disulfide bond (Supplementary Fig. 9). RESULTS 90 95 dimer oligomeric_state Supporting this, MS analyses under denaturing conditions showed that haem-mediated PGRMC1 dimer is completely dissociated into monomer, indicating that dimerization of this kind is not mediated by any covalent bond such as disulfide bond (Supplementary Fig. 9). RESULTS 127 134 monomer oligomeric_state Supporting this, MS analyses under denaturing conditions showed that haem-mediated PGRMC1 dimer is completely dissociated into monomer, indicating that dimerization of this kind is not mediated by any covalent bond such as disulfide bond (Supplementary Fig. 9). RESULTS 152 164 dimerization oligomeric_state Supporting this, MS analyses under denaturing conditions showed that haem-mediated PGRMC1 dimer is completely dissociated into monomer, indicating that dimerization of this kind is not mediated by any covalent bond such as disulfide bond (Supplementary Fig. 9). RESULTS 223 237 disulfide bond ptm Supporting this, MS analyses under denaturing conditions showed that haem-mediated PGRMC1 dimer is completely dissociated into monomer, indicating that dimerization of this kind is not mediated by any covalent bond such as disulfide bond (Supplementary Fig. 9). RESULTS 21 25 haem chemical We also analysed the haem-dependent dimerization of PGRMC1 by diffusion-ordered NMR spectroscopy (DOSY) analyses (Table 2, Supplementary Fig. 10). RESULTS 36 48 dimerization oligomeric_state We also analysed the haem-dependent dimerization of PGRMC1 by diffusion-ordered NMR spectroscopy (DOSY) analyses (Table 2, Supplementary Fig. 10). RESULTS 52 58 PGRMC1 protein We also analysed the haem-dependent dimerization of PGRMC1 by diffusion-ordered NMR spectroscopy (DOSY) analyses (Table 2, Supplementary Fig. 10). RESULTS 62 96 diffusion-ordered NMR spectroscopy experimental_method We also analysed the haem-dependent dimerization of PGRMC1 by diffusion-ordered NMR spectroscopy (DOSY) analyses (Table 2, Supplementary Fig. 10). RESULTS 98 102 DOSY experimental_method We also analysed the haem-dependent dimerization of PGRMC1 by diffusion-ordered NMR spectroscopy (DOSY) analyses (Table 2, Supplementary Fig. 10). RESULTS 31 50 hydrodynamic radius evidence The results suggested that the hydrodynamic radius of haem-bound PGRMC1 is larger than that of apo-PGRMC1. RESULTS 54 64 haem-bound protein_state The results suggested that the hydrodynamic radius of haem-bound PGRMC1 is larger than that of apo-PGRMC1. RESULTS 65 71 PGRMC1 protein The results suggested that the hydrodynamic radius of haem-bound PGRMC1 is larger than that of apo-PGRMC1. RESULTS 95 98 apo protein_state The results suggested that the hydrodynamic radius of haem-bound PGRMC1 is larger than that of apo-PGRMC1. RESULTS 99 105 PGRMC1 protein The results suggested that the hydrodynamic radius of haem-bound PGRMC1 is larger than that of apo-PGRMC1. RESULTS 52 64 dimerization oligomeric_state To further evaluate changes in molecular weights in dimerization of PGRMC1, sedimentation velocity analytical ultracentrifugation (SV-AUC) analysis was carried out. RESULTS 68 74 PGRMC1 protein To further evaluate changes in molecular weights in dimerization of PGRMC1, sedimentation velocity analytical ultracentrifugation (SV-AUC) analysis was carried out. RESULTS 76 129 sedimentation velocity analytical ultracentrifugation experimental_method To further evaluate changes in molecular weights in dimerization of PGRMC1, sedimentation velocity analytical ultracentrifugation (SV-AUC) analysis was carried out. RESULTS 131 137 SV-AUC experimental_method To further evaluate changes in molecular weights in dimerization of PGRMC1, sedimentation velocity analytical ultracentrifugation (SV-AUC) analysis was carried out. RESULTS 12 21 wild-type protein_state Whereas the wild-type (wt) apo-PGRMC1 appeared at a 1.9 S peak as monomer, the haem-binding PGRMC1 was converted into dimer at a 3.1 S peak (Fig. 2b). RESULTS 23 25 wt protein_state Whereas the wild-type (wt) apo-PGRMC1 appeared at a 1.9 S peak as monomer, the haem-binding PGRMC1 was converted into dimer at a 3.1 S peak (Fig. 2b). RESULTS 27 30 apo protein_state Whereas the wild-type (wt) apo-PGRMC1 appeared at a 1.9 S peak as monomer, the haem-binding PGRMC1 was converted into dimer at a 3.1 S peak (Fig. 2b). RESULTS 31 37 PGRMC1 protein Whereas the wild-type (wt) apo-PGRMC1 appeared at a 1.9 S peak as monomer, the haem-binding PGRMC1 was converted into dimer at a 3.1 S peak (Fig. 2b). RESULTS 66 73 monomer oligomeric_state Whereas the wild-type (wt) apo-PGRMC1 appeared at a 1.9 S peak as monomer, the haem-binding PGRMC1 was converted into dimer at a 3.1 S peak (Fig. 2b). RESULTS 79 83 haem chemical Whereas the wild-type (wt) apo-PGRMC1 appeared at a 1.9 S peak as monomer, the haem-binding PGRMC1 was converted into dimer at a 3.1 S peak (Fig. 2b). RESULTS 92 98 PGRMC1 protein Whereas the wild-type (wt) apo-PGRMC1 appeared at a 1.9 S peak as monomer, the haem-binding PGRMC1 was converted into dimer at a 3.1 S peak (Fig. 2b). RESULTS 118 123 dimer oligomeric_state Whereas the wild-type (wt) apo-PGRMC1 appeared at a 1.9 S peak as monomer, the haem-binding PGRMC1 was converted into dimer at a 3.1 S peak (Fig. 2b). RESULTS 15 20 C129S mutant Similarly, the C129S mutant of PGRMC1 converted from monomer to dimer by binding to haem (Fig. 2b). RESULTS 21 27 mutant protein_state Similarly, the C129S mutant of PGRMC1 converted from monomer to dimer by binding to haem (Fig. 2b). RESULTS 31 37 PGRMC1 protein Similarly, the C129S mutant of PGRMC1 converted from monomer to dimer by binding to haem (Fig. 2b). RESULTS 53 60 monomer oligomeric_state Similarly, the C129S mutant of PGRMC1 converted from monomer to dimer by binding to haem (Fig. 2b). RESULTS 64 69 dimer oligomeric_state Similarly, the C129S mutant of PGRMC1 converted from monomer to dimer by binding to haem (Fig. 2b). RESULTS 84 88 haem chemical Similarly, the C129S mutant of PGRMC1 converted from monomer to dimer by binding to haem (Fig. 2b). RESULTS 0 6 SV-AUC experimental_method SV-AUC analyses also allowed us to examine the stability of haem/PGRMC1 dimer. RESULTS 60 64 haem chemical SV-AUC analyses also allowed us to examine the stability of haem/PGRMC1 dimer. RESULTS 65 71 PGRMC1 protein SV-AUC analyses also allowed us to examine the stability of haem/PGRMC1 dimer. RESULTS 72 77 dimer oligomeric_state SV-AUC analyses also allowed us to examine the stability of haem/PGRMC1 dimer. RESULTS 68 78 haem-bound protein_state To this end, we used different concentrations (3.5–147 μmol l−1) of haem-bound PGRMC1 protein (a.a. 72–195), which were identical to that used in the crystallographic analysis. RESULTS 79 85 PGRMC1 protein To this end, we used different concentrations (3.5–147 μmol l−1) of haem-bound PGRMC1 protein (a.a. 72–195), which were identical to that used in the crystallographic analysis. RESULTS 100 106 72–195 residue_range To this end, we used different concentrations (3.5–147 μmol l−1) of haem-bound PGRMC1 protein (a.a. 72–195), which were identical to that used in the crystallographic analysis. RESULTS 150 175 crystallographic analysis experimental_method To this end, we used different concentrations (3.5–147 μmol l−1) of haem-bound PGRMC1 protein (a.a. 72–195), which were identical to that used in the crystallographic analysis. RESULTS 4 30 sedimentation coefficients evidence The sedimentation coefficients calculated on the basis of the crystal structure were 1.71 S for monomer and 2.56 S for dimer (Supplementary Fig. 11, upper panel). RESULTS 62 79 crystal structure evidence The sedimentation coefficients calculated on the basis of the crystal structure were 1.71 S for monomer and 2.56 S for dimer (Supplementary Fig. 11, upper panel). RESULTS 96 103 monomer oligomeric_state The sedimentation coefficients calculated on the basis of the crystal structure were 1.71 S for monomer and 2.56 S for dimer (Supplementary Fig. 11, upper panel). RESULTS 119 124 dimer oligomeric_state The sedimentation coefficients calculated on the basis of the crystal structure were 1.71 S for monomer and 2.56 S for dimer (Supplementary Fig. 11, upper panel). RESULTS 28 34 PGRMC1 protein The results showed that the PGRMC1 dimer is not dissociated into monomer at all concentrations examined (Supplementary Fig. 11, lower panel), suggesting that the Kd value of haem-mediated dimer of PGRMC1 is under 3.5 μmol l−1. RESULTS 35 40 dimer oligomeric_state The results showed that the PGRMC1 dimer is not dissociated into monomer at all concentrations examined (Supplementary Fig. 11, lower panel), suggesting that the Kd value of haem-mediated dimer of PGRMC1 is under 3.5 μmol l−1. RESULTS 65 72 monomer oligomeric_state The results showed that the PGRMC1 dimer is not dissociated into monomer at all concentrations examined (Supplementary Fig. 11, lower panel), suggesting that the Kd value of haem-mediated dimer of PGRMC1 is under 3.5 μmol l−1. RESULTS 162 164 Kd evidence The results showed that the PGRMC1 dimer is not dissociated into monomer at all concentrations examined (Supplementary Fig. 11, lower panel), suggesting that the Kd value of haem-mediated dimer of PGRMC1 is under 3.5 μmol l−1. RESULTS 174 178 haem chemical The results showed that the PGRMC1 dimer is not dissociated into monomer at all concentrations examined (Supplementary Fig. 11, lower panel), suggesting that the Kd value of haem-mediated dimer of PGRMC1 is under 3.5 μmol l−1. RESULTS 188 193 dimer oligomeric_state The results showed that the PGRMC1 dimer is not dissociated into monomer at all concentrations examined (Supplementary Fig. 11, lower panel), suggesting that the Kd value of haem-mediated dimer of PGRMC1 is under 3.5 μmol l−1. RESULTS 197 203 PGRMC1 protein The results showed that the PGRMC1 dimer is not dissociated into monomer at all concentrations examined (Supplementary Fig. 11, lower panel), suggesting that the Kd value of haem-mediated dimer of PGRMC1 is under 3.5 μmol l−1. RESULTS 38 44 PGRMC1 protein A value of this kind implies that the PGRMC1 dimer is more stable than other dimers of extracellular domain of membrane proteins such as Toll like receptor 9 (dimerization Kd of 20 μmol l−1) (ref.) and plexin A2 receptor (dimerization Kd higher than 300 μmol l−1) (ref.). RESULTS 45 50 dimer oligomeric_state A value of this kind implies that the PGRMC1 dimer is more stable than other dimers of extracellular domain of membrane proteins such as Toll like receptor 9 (dimerization Kd of 20 μmol l−1) (ref.) and plexin A2 receptor (dimerization Kd higher than 300 μmol l−1) (ref.). RESULTS 77 83 dimers oligomeric_state A value of this kind implies that the PGRMC1 dimer is more stable than other dimers of extracellular domain of membrane proteins such as Toll like receptor 9 (dimerization Kd of 20 μmol l−1) (ref.) and plexin A2 receptor (dimerization Kd higher than 300 μmol l−1) (ref.). RESULTS 87 107 extracellular domain structure_element A value of this kind implies that the PGRMC1 dimer is more stable than other dimers of extracellular domain of membrane proteins such as Toll like receptor 9 (dimerization Kd of 20 μmol l−1) (ref.) and plexin A2 receptor (dimerization Kd higher than 300 μmol l−1) (ref.). RESULTS 111 128 membrane proteins protein_type A value of this kind implies that the PGRMC1 dimer is more stable than other dimers of extracellular domain of membrane proteins such as Toll like receptor 9 (dimerization Kd of 20 μmol l−1) (ref.) and plexin A2 receptor (dimerization Kd higher than 300 μmol l−1) (ref.). RESULTS 137 157 Toll like receptor 9 protein A value of this kind implies that the PGRMC1 dimer is more stable than other dimers of extracellular domain of membrane proteins such as Toll like receptor 9 (dimerization Kd of 20 μmol l−1) (ref.) and plexin A2 receptor (dimerization Kd higher than 300 μmol l−1) (ref.). RESULTS 159 171 dimerization oligomeric_state A value of this kind implies that the PGRMC1 dimer is more stable than other dimers of extracellular domain of membrane proteins such as Toll like receptor 9 (dimerization Kd of 20 μmol l−1) (ref.) and plexin A2 receptor (dimerization Kd higher than 300 μmol l−1) (ref.). RESULTS 172 174 Kd evidence A value of this kind implies that the PGRMC1 dimer is more stable than other dimers of extracellular domain of membrane proteins such as Toll like receptor 9 (dimerization Kd of 20 μmol l−1) (ref.) and plexin A2 receptor (dimerization Kd higher than 300 μmol l−1) (ref.). RESULTS 202 220 plexin A2 receptor protein A value of this kind implies that the PGRMC1 dimer is more stable than other dimers of extracellular domain of membrane proteins such as Toll like receptor 9 (dimerization Kd of 20 μmol l−1) (ref.) and plexin A2 receptor (dimerization Kd higher than 300 μmol l−1) (ref.). RESULTS 222 234 dimerization oligomeric_state A value of this kind implies that the PGRMC1 dimer is more stable than other dimers of extracellular domain of membrane proteins such as Toll like receptor 9 (dimerization Kd of 20 μmol l−1) (ref.) and plexin A2 receptor (dimerization Kd higher than 300 μmol l−1) (ref.). RESULTS 235 237 Kd evidence A value of this kind implies that the PGRMC1 dimer is more stable than other dimers of extracellular domain of membrane proteins such as Toll like receptor 9 (dimerization Kd of 20 μmol l−1) (ref.) and plexin A2 receptor (dimerization Kd higher than 300 μmol l−1) (ref.). RESULTS 43 46 apo protein_state The current analytical data confirmed that apo-PGRMC1 monomer converts into dimer by binding to haem in solution (Table 2). RESULTS 47 53 PGRMC1 protein The current analytical data confirmed that apo-PGRMC1 monomer converts into dimer by binding to haem in solution (Table 2). RESULTS 54 61 monomer oligomeric_state The current analytical data confirmed that apo-PGRMC1 monomer converts into dimer by binding to haem in solution (Table 2). RESULTS 76 81 dimer oligomeric_state The current analytical data confirmed that apo-PGRMC1 monomer converts into dimer by binding to haem in solution (Table 2). RESULTS 96 100 haem chemical The current analytical data confirmed that apo-PGRMC1 monomer converts into dimer by binding to haem in solution (Table 2). RESULTS 18 44 haem titration experiments experimental_method We also showed by haem titration experiments that haem binding to PGRMC1 was of low affinity with a Kd value of 50 nmol l−1; this is comparable with that of iron regulatory protein 2, which is known to be regulated by intracellular levels of haem (Fig. 2c and Supplementary Table 1). RESULTS 50 54 haem chemical We also showed by haem titration experiments that haem binding to PGRMC1 was of low affinity with a Kd value of 50 nmol l−1; this is comparable with that of iron regulatory protein 2, which is known to be regulated by intracellular levels of haem (Fig. 2c and Supplementary Table 1). RESULTS 66 72 PGRMC1 protein We also showed by haem titration experiments that haem binding to PGRMC1 was of low affinity with a Kd value of 50 nmol l−1; this is comparable with that of iron regulatory protein 2, which is known to be regulated by intracellular levels of haem (Fig. 2c and Supplementary Table 1). RESULTS 100 102 Kd evidence We also showed by haem titration experiments that haem binding to PGRMC1 was of low affinity with a Kd value of 50 nmol l−1; this is comparable with that of iron regulatory protein 2, which is known to be regulated by intracellular levels of haem (Fig. 2c and Supplementary Table 1). RESULTS 157 182 iron regulatory protein 2 protein We also showed by haem titration experiments that haem binding to PGRMC1 was of low affinity with a Kd value of 50 nmol l−1; this is comparable with that of iron regulatory protein 2, which is known to be regulated by intracellular levels of haem (Fig. 2c and Supplementary Table 1). RESULTS 242 246 haem chemical We also showed by haem titration experiments that haem binding to PGRMC1 was of low affinity with a Kd value of 50 nmol l−1; this is comparable with that of iron regulatory protein 2, which is known to be regulated by intracellular levels of haem (Fig. 2c and Supplementary Table 1). RESULTS 58 64 PGRMC1 protein These results raised the possibility that the function of PGRMC1 is regulated by intracellular haem concentrations. RESULTS 95 99 haem chemical These results raised the possibility that the function of PGRMC1 is regulated by intracellular haem concentrations. RESULTS 0 2 CO chemical CO inhibits haem-dependent dimerization of PGRMC1 RESULTS 12 16 haem chemical CO inhibits haem-dependent dimerization of PGRMC1 RESULTS 27 39 dimerization oligomeric_state CO inhibits haem-dependent dimerization of PGRMC1 RESULTS 43 49 PGRMC1 protein CO inhibits haem-dependent dimerization of PGRMC1 RESULTS 0 25 Crystallographic analyses experimental_method Crystallographic analyses revealed that Tyr113 of PGRMC1 is an axial ligand for haem and contributes to haem-dependent dimerization (Fig. 1a). RESULTS 40 46 Tyr113 residue_name_number Crystallographic analyses revealed that Tyr113 of PGRMC1 is an axial ligand for haem and contributes to haem-dependent dimerization (Fig. 1a). RESULTS 50 56 PGRMC1 protein Crystallographic analyses revealed that Tyr113 of PGRMC1 is an axial ligand for haem and contributes to haem-dependent dimerization (Fig. 1a). RESULTS 80 84 haem chemical Crystallographic analyses revealed that Tyr113 of PGRMC1 is an axial ligand for haem and contributes to haem-dependent dimerization (Fig. 1a). RESULTS 104 108 haem chemical Crystallographic analyses revealed that Tyr113 of PGRMC1 is an axial ligand for haem and contributes to haem-dependent dimerization (Fig. 1a). RESULTS 119 131 dimerization oligomeric_state Crystallographic analyses revealed that Tyr113 of PGRMC1 is an axial ligand for haem and contributes to haem-dependent dimerization (Fig. 1a). RESULTS 12 30 UV-visible spectra evidence Analysis of UV-visible spectra revealed that the heme of PGRMC1 is reducible from ferric to ferrous state, thus allowing CO binding (Fig. 3a). RESULTS 49 53 heme chemical Analysis of UV-visible spectra revealed that the heme of PGRMC1 is reducible from ferric to ferrous state, thus allowing CO binding (Fig. 3a). RESULTS 57 63 PGRMC1 protein Analysis of UV-visible spectra revealed that the heme of PGRMC1 is reducible from ferric to ferrous state, thus allowing CO binding (Fig. 3a). RESULTS 82 88 ferric protein_state Analysis of UV-visible spectra revealed that the heme of PGRMC1 is reducible from ferric to ferrous state, thus allowing CO binding (Fig. 3a). RESULTS 92 99 ferrous protein_state Analysis of UV-visible spectra revealed that the heme of PGRMC1 is reducible from ferric to ferrous state, thus allowing CO binding (Fig. 3a). RESULTS 121 123 CO chemical Analysis of UV-visible spectra revealed that the heme of PGRMC1 is reducible from ferric to ferrous state, thus allowing CO binding (Fig. 3a). RESULTS 17 36 UV-visible spectrum evidence Furthermore, the UV-visible spectrum of the wild type PGRMC1 was the same as that of the C129S mutant of PGRMC1, and the R/Z ratio determined by the intensities between the Soret band (394 nm) peak and the 274-nm peak showed that these proteins were fully loaded with haem (Supplementary Fig. 12). RESULTS 44 53 wild type protein_state Furthermore, the UV-visible spectrum of the wild type PGRMC1 was the same as that of the C129S mutant of PGRMC1, and the R/Z ratio determined by the intensities between the Soret band (394 nm) peak and the 274-nm peak showed that these proteins were fully loaded with haem (Supplementary Fig. 12). RESULTS 54 60 PGRMC1 protein Furthermore, the UV-visible spectrum of the wild type PGRMC1 was the same as that of the C129S mutant of PGRMC1, and the R/Z ratio determined by the intensities between the Soret band (394 nm) peak and the 274-nm peak showed that these proteins were fully loaded with haem (Supplementary Fig. 12). RESULTS 89 94 C129S mutant Furthermore, the UV-visible spectrum of the wild type PGRMC1 was the same as that of the C129S mutant of PGRMC1, and the R/Z ratio determined by the intensities between the Soret band (394 nm) peak and the 274-nm peak showed that these proteins were fully loaded with haem (Supplementary Fig. 12). RESULTS 95 101 mutant protein_state Furthermore, the UV-visible spectrum of the wild type PGRMC1 was the same as that of the C129S mutant of PGRMC1, and the R/Z ratio determined by the intensities between the Soret band (394 nm) peak and the 274-nm peak showed that these proteins were fully loaded with haem (Supplementary Fig. 12). RESULTS 105 111 PGRMC1 protein Furthermore, the UV-visible spectrum of the wild type PGRMC1 was the same as that of the C129S mutant of PGRMC1, and the R/Z ratio determined by the intensities between the Soret band (394 nm) peak and the 274-nm peak showed that these proteins were fully loaded with haem (Supplementary Fig. 12). RESULTS 121 130 R/Z ratio evidence Furthermore, the UV-visible spectrum of the wild type PGRMC1 was the same as that of the C129S mutant of PGRMC1, and the R/Z ratio determined by the intensities between the Soret band (394 nm) peak and the 274-nm peak showed that these proteins were fully loaded with haem (Supplementary Fig. 12). RESULTS 250 267 fully loaded with protein_state Furthermore, the UV-visible spectrum of the wild type PGRMC1 was the same as that of the C129S mutant of PGRMC1, and the R/Z ratio determined by the intensities between the Soret band (394 nm) peak and the 274-nm peak showed that these proteins were fully loaded with haem (Supplementary Fig. 12). RESULTS 268 272 haem chemical Furthermore, the UV-visible spectrum of the wild type PGRMC1 was the same as that of the C129S mutant of PGRMC1, and the R/Z ratio determined by the intensities between the Soret band (394 nm) peak and the 274-nm peak showed that these proteins were fully loaded with haem (Supplementary Fig. 12). RESULTS 16 22 ferric protein_state Analysis of the ferric form of PGRMC1 using resonance Raman spectroscopy (Supplementary Fig. 13) showed that the relative intensity of oxidation and spin state marker bands (ν4 and ν3) is close to 1.0, which is consistent with it being a haem protein with a proximal Tyr coordination. RESULTS 31 37 PGRMC1 protein Analysis of the ferric form of PGRMC1 using resonance Raman spectroscopy (Supplementary Fig. 13) showed that the relative intensity of oxidation and spin state marker bands (ν4 and ν3) is close to 1.0, which is consistent with it being a haem protein with a proximal Tyr coordination. RESULTS 44 72 resonance Raman spectroscopy experimental_method Analysis of the ferric form of PGRMC1 using resonance Raman spectroscopy (Supplementary Fig. 13) showed that the relative intensity of oxidation and spin state marker bands (ν4 and ν3) is close to 1.0, which is consistent with it being a haem protein with a proximal Tyr coordination. RESULTS 238 242 haem chemical Analysis of the ferric form of PGRMC1 using resonance Raman spectroscopy (Supplementary Fig. 13) showed that the relative intensity of oxidation and spin state marker bands (ν4 and ν3) is close to 1.0, which is consistent with it being a haem protein with a proximal Tyr coordination. RESULTS 267 270 Tyr residue_name Analysis of the ferric form of PGRMC1 using resonance Raman spectroscopy (Supplementary Fig. 13) showed that the relative intensity of oxidation and spin state marker bands (ν4 and ν3) is close to 1.0, which is consistent with it being a haem protein with a proximal Tyr coordination. RESULTS 11 22 Raman shift evidence A specific Raman shift peaking at vFe–CO=500 cm−1 demonstrated that the CO-bound haem of PGRMC1 is six-coordinated (Supplementary Fig. 13). RESULTS 72 80 CO-bound protein_state A specific Raman shift peaking at vFe–CO=500 cm−1 demonstrated that the CO-bound haem of PGRMC1 is six-coordinated (Supplementary Fig. 13). RESULTS 81 85 haem chemical A specific Raman shift peaking at vFe–CO=500 cm−1 demonstrated that the CO-bound haem of PGRMC1 is six-coordinated (Supplementary Fig. 13). RESULTS 89 95 PGRMC1 protein A specific Raman shift peaking at vFe–CO=500 cm−1 demonstrated that the CO-bound haem of PGRMC1 is six-coordinated (Supplementary Fig. 13). RESULTS 6 12 PGRMC1 protein Since PGRMC1 dimerization involves the open surface of haem on the opposite side of the axial Tyr113, no space for CO binding is available in the dimeric structure (Fig. 3b). RESULTS 13 25 dimerization oligomeric_state Since PGRMC1 dimerization involves the open surface of haem on the opposite side of the axial Tyr113, no space for CO binding is available in the dimeric structure (Fig. 3b). RESULTS 44 51 surface site Since PGRMC1 dimerization involves the open surface of haem on the opposite side of the axial Tyr113, no space for CO binding is available in the dimeric structure (Fig. 3b). RESULTS 55 59 haem chemical Since PGRMC1 dimerization involves the open surface of haem on the opposite side of the axial Tyr113, no space for CO binding is available in the dimeric structure (Fig. 3b). RESULTS 94 100 Tyr113 residue_name_number Since PGRMC1 dimerization involves the open surface of haem on the opposite side of the axial Tyr113, no space for CO binding is available in the dimeric structure (Fig. 3b). RESULTS 115 117 CO chemical Since PGRMC1 dimerization involves the open surface of haem on the opposite side of the axial Tyr113, no space for CO binding is available in the dimeric structure (Fig. 3b). RESULTS 146 153 dimeric oligomeric_state Since PGRMC1 dimerization involves the open surface of haem on the opposite side of the axial Tyr113, no space for CO binding is available in the dimeric structure (Fig. 3b). RESULTS 154 163 structure evidence Since PGRMC1 dimerization involves the open surface of haem on the opposite side of the axial Tyr113, no space for CO binding is available in the dimeric structure (Fig. 3b). RESULTS 27 29 CO chemical This prompted us to ask if CO binding to haem causes dissociation of the PGRMC1 dimer. RESULTS 41 45 haem chemical This prompted us to ask if CO binding to haem causes dissociation of the PGRMC1 dimer. RESULTS 73 79 PGRMC1 protein This prompted us to ask if CO binding to haem causes dissociation of the PGRMC1 dimer. RESULTS 80 85 dimer oligomeric_state This prompted us to ask if CO binding to haem causes dissociation of the PGRMC1 dimer. RESULTS 12 41 gel filtration chromatography experimental_method Analysis by gel filtration chromatography revealed that the relative molecular sizes of the wild-type and the C129S mutant of PGRMC1 are increased by adding haem to apo-PGRMC1 regardless of the oxidation state of the iron (Fig. 3c), which is in agreement with the results in Table 1. RESULTS 92 101 wild-type protein_state Analysis by gel filtration chromatography revealed that the relative molecular sizes of the wild-type and the C129S mutant of PGRMC1 are increased by adding haem to apo-PGRMC1 regardless of the oxidation state of the iron (Fig. 3c), which is in agreement with the results in Table 1. RESULTS 110 115 C129S mutant Analysis by gel filtration chromatography revealed that the relative molecular sizes of the wild-type and the C129S mutant of PGRMC1 are increased by adding haem to apo-PGRMC1 regardless of the oxidation state of the iron (Fig. 3c), which is in agreement with the results in Table 1. RESULTS 116 122 mutant protein_state Analysis by gel filtration chromatography revealed that the relative molecular sizes of the wild-type and the C129S mutant of PGRMC1 are increased by adding haem to apo-PGRMC1 regardless of the oxidation state of the iron (Fig. 3c), which is in agreement with the results in Table 1. RESULTS 126 132 PGRMC1 protein Analysis by gel filtration chromatography revealed that the relative molecular sizes of the wild-type and the C129S mutant of PGRMC1 are increased by adding haem to apo-PGRMC1 regardless of the oxidation state of the iron (Fig. 3c), which is in agreement with the results in Table 1. RESULTS 157 161 haem chemical Analysis by gel filtration chromatography revealed that the relative molecular sizes of the wild-type and the C129S mutant of PGRMC1 are increased by adding haem to apo-PGRMC1 regardless of the oxidation state of the iron (Fig. 3c), which is in agreement with the results in Table 1. RESULTS 165 168 apo protein_state Analysis by gel filtration chromatography revealed that the relative molecular sizes of the wild-type and the C129S mutant of PGRMC1 are increased by adding haem to apo-PGRMC1 regardless of the oxidation state of the iron (Fig. 3c), which is in agreement with the results in Table 1. RESULTS 169 175 PGRMC1 protein Analysis by gel filtration chromatography revealed that the relative molecular sizes of the wild-type and the C129S mutant of PGRMC1 are increased by adding haem to apo-PGRMC1 regardless of the oxidation state of the iron (Fig. 3c), which is in agreement with the results in Table 1. RESULTS 217 221 iron chemical Analysis by gel filtration chromatography revealed that the relative molecular sizes of the wild-type and the C129S mutant of PGRMC1 are increased by adding haem to apo-PGRMC1 regardless of the oxidation state of the iron (Fig. 3c), which is in agreement with the results in Table 1. RESULTS 0 2 CO chemical CO application to ferrous PGRMC1 abolished the haem-dependent increase in its molecular size. RESULTS 18 25 ferrous protein_state CO application to ferrous PGRMC1 abolished the haem-dependent increase in its molecular size. RESULTS 26 32 PGRMC1 protein CO application to ferrous PGRMC1 abolished the haem-dependent increase in its molecular size. RESULTS 47 51 haem chemical CO application to ferrous PGRMC1 abolished the haem-dependent increase in its molecular size. RESULTS 37 48 presence of protein_state Under this reducing condition in the presence of dithionite, analyses of UV-visible spectra indicated that CO-binding with haem-PGRMC1 is stable, showing only 20% reduction of the absorbance at 412 nm within 2 h (Supplementary Fig. 14). RESULTS 49 59 dithionite chemical Under this reducing condition in the presence of dithionite, analyses of UV-visible spectra indicated that CO-binding with haem-PGRMC1 is stable, showing only 20% reduction of the absorbance at 412 nm within 2 h (Supplementary Fig. 14). RESULTS 73 91 UV-visible spectra evidence Under this reducing condition in the presence of dithionite, analyses of UV-visible spectra indicated that CO-binding with haem-PGRMC1 is stable, showing only 20% reduction of the absorbance at 412 nm within 2 h (Supplementary Fig. 14). RESULTS 107 109 CO chemical Under this reducing condition in the presence of dithionite, analyses of UV-visible spectra indicated that CO-binding with haem-PGRMC1 is stable, showing only 20% reduction of the absorbance at 412 nm within 2 h (Supplementary Fig. 14). RESULTS 123 134 haem-PGRMC1 complex_assembly Under this reducing condition in the presence of dithionite, analyses of UV-visible spectra indicated that CO-binding with haem-PGRMC1 is stable, showing only 20% reduction of the absorbance at 412 nm within 2 h (Supplementary Fig. 14). RESULTS 138 144 stable protein_state Under this reducing condition in the presence of dithionite, analyses of UV-visible spectra indicated that CO-binding with haem-PGRMC1 is stable, showing only 20% reduction of the absorbance at 412 nm within 2 h (Supplementary Fig. 14). RESULTS 17 26 Tyr113Phe mutant Furthermore, the Tyr113Phe (Y113F) mutant of PGRMC1 was not responsive to haem. RESULTS 28 33 Y113F mutant Furthermore, the Tyr113Phe (Y113F) mutant of PGRMC1 was not responsive to haem. RESULTS 35 41 mutant protein_state Furthermore, the Tyr113Phe (Y113F) mutant of PGRMC1 was not responsive to haem. RESULTS 45 51 PGRMC1 protein Furthermore, the Tyr113Phe (Y113F) mutant of PGRMC1 was not responsive to haem. RESULTS 74 78 haem chemical Furthermore, the Tyr113Phe (Y113F) mutant of PGRMC1 was not responsive to haem. RESULTS 27 29 CO chemical These results suggest that CO favours the six-coordinate form of haem and interferes with the haem-mediated dimerization of PGRMC1. RESULTS 65 69 haem chemical These results suggest that CO favours the six-coordinate form of haem and interferes with the haem-mediated dimerization of PGRMC1. RESULTS 94 98 haem chemical These results suggest that CO favours the six-coordinate form of haem and interferes with the haem-mediated dimerization of PGRMC1. RESULTS 108 120 dimerization oligomeric_state These results suggest that CO favours the six-coordinate form of haem and interferes with the haem-mediated dimerization of PGRMC1. RESULTS 124 130 PGRMC1 protein These results suggest that CO favours the six-coordinate form of haem and interferes with the haem-mediated dimerization of PGRMC1. RESULTS 37 39 CO chemical To examine the inhibitory effects of CO on haem-mediated PGRMC1 dimerization, SV-AUC analysis was carried out. RESULTS 43 47 haem chemical To examine the inhibitory effects of CO on haem-mediated PGRMC1 dimerization, SV-AUC analysis was carried out. RESULTS 57 63 PGRMC1 protein To examine the inhibitory effects of CO on haem-mediated PGRMC1 dimerization, SV-AUC analysis was carried out. RESULTS 64 76 dimerization oligomeric_state To examine the inhibitory effects of CO on haem-mediated PGRMC1 dimerization, SV-AUC analysis was carried out. RESULTS 78 84 SV-AUC experimental_method To examine the inhibitory effects of CO on haem-mediated PGRMC1 dimerization, SV-AUC analysis was carried out. RESULTS 30 34 haem chemical The peak corresponding to the haem/PGRMC1 dimer was detected under reducing conditions in the presence of dithionite (Supplementary Fig. 15, middle panel). RESULTS 35 41 PGRMC1 protein The peak corresponding to the haem/PGRMC1 dimer was detected under reducing conditions in the presence of dithionite (Supplementary Fig. 15, middle panel). RESULTS 42 47 dimer oligomeric_state The peak corresponding to the haem/PGRMC1 dimer was detected under reducing conditions in the presence of dithionite (Supplementary Fig. 15, middle panel). RESULTS 94 105 presence of protein_state The peak corresponding to the haem/PGRMC1 dimer was detected under reducing conditions in the presence of dithionite (Supplementary Fig. 15, middle panel). RESULTS 106 116 dithionite chemical The peak corresponding to the haem/PGRMC1 dimer was detected under reducing conditions in the presence of dithionite (Supplementary Fig. 15, middle panel). RESULTS 27 29 CO chemical Under these circumstances, CO application induced dissociation of the haem-mediated dimers of PGRMC1 to generate a peak of monomers (Supplementary Fig. 15, lower panel). RESULTS 70 74 haem chemical Under these circumstances, CO application induced dissociation of the haem-mediated dimers of PGRMC1 to generate a peak of monomers (Supplementary Fig. 15, lower panel). RESULTS 84 90 dimers oligomeric_state Under these circumstances, CO application induced dissociation of the haem-mediated dimers of PGRMC1 to generate a peak of monomers (Supplementary Fig. 15, lower panel). RESULTS 94 100 PGRMC1 protein Under these circumstances, CO application induced dissociation of the haem-mediated dimers of PGRMC1 to generate a peak of monomers (Supplementary Fig. 15, lower panel). RESULTS 123 131 monomers oligomeric_state Under these circumstances, CO application induced dissociation of the haem-mediated dimers of PGRMC1 to generate a peak of monomers (Supplementary Fig. 15, lower panel). RESULTS 76 82 PGRMC1 protein These observations raised the transition model for structural regulation of PGRMC1 in response to haem (Fig. 3d). RESULTS 98 102 haem chemical These observations raised the transition model for structural regulation of PGRMC1 in response to haem (Fig. 3d). RESULTS 20 23 apo protein_state As mentioned above, apo-PGRMC1 exists as monomer. RESULTS 24 30 PGRMC1 protein As mentioned above, apo-PGRMC1 exists as monomer. RESULTS 41 48 monomer oligomeric_state As mentioned above, apo-PGRMC1 exists as monomer. RESULTS 16 20 haem chemical By binding with haem (binding Kd=50 nmol l−1), PGRMC1 forms a stable dimer (dimerization Kd<<3.5 μmol l−1) through stacking of the two open surfaces of the five-coordinated haem molecules in each monomer. RESULTS 30 32 Kd evidence By binding with haem (binding Kd=50 nmol l−1), PGRMC1 forms a stable dimer (dimerization Kd<<3.5 μmol l−1) through stacking of the two open surfaces of the five-coordinated haem molecules in each monomer. RESULTS 47 53 PGRMC1 protein By binding with haem (binding Kd=50 nmol l−1), PGRMC1 forms a stable dimer (dimerization Kd<<3.5 μmol l−1) through stacking of the two open surfaces of the five-coordinated haem molecules in each monomer. RESULTS 62 68 stable protein_state By binding with haem (binding Kd=50 nmol l−1), PGRMC1 forms a stable dimer (dimerization Kd<<3.5 μmol l−1) through stacking of the two open surfaces of the five-coordinated haem molecules in each monomer. RESULTS 69 74 dimer oligomeric_state By binding with haem (binding Kd=50 nmol l−1), PGRMC1 forms a stable dimer (dimerization Kd<<3.5 μmol l−1) through stacking of the two open surfaces of the five-coordinated haem molecules in each monomer. RESULTS 76 88 dimerization oligomeric_state By binding with haem (binding Kd=50 nmol l−1), PGRMC1 forms a stable dimer (dimerization Kd<<3.5 μmol l−1) through stacking of the two open surfaces of the five-coordinated haem molecules in each monomer. RESULTS 89 91 Kd evidence By binding with haem (binding Kd=50 nmol l−1), PGRMC1 forms a stable dimer (dimerization Kd<<3.5 μmol l−1) through stacking of the two open surfaces of the five-coordinated haem molecules in each monomer. RESULTS 115 123 stacking bond_interaction By binding with haem (binding Kd=50 nmol l−1), PGRMC1 forms a stable dimer (dimerization Kd<<3.5 μmol l−1) through stacking of the two open surfaces of the five-coordinated haem molecules in each monomer. RESULTS 140 148 surfaces site By binding with haem (binding Kd=50 nmol l−1), PGRMC1 forms a stable dimer (dimerization Kd<<3.5 μmol l−1) through stacking of the two open surfaces of the five-coordinated haem molecules in each monomer. RESULTS 173 177 haem chemical By binding with haem (binding Kd=50 nmol l−1), PGRMC1 forms a stable dimer (dimerization Kd<<3.5 μmol l−1) through stacking of the two open surfaces of the five-coordinated haem molecules in each monomer. RESULTS 196 203 monomer oligomeric_state By binding with haem (binding Kd=50 nmol l−1), PGRMC1 forms a stable dimer (dimerization Kd<<3.5 μmol l−1) through stacking of the two open surfaces of the five-coordinated haem molecules in each monomer. RESULTS 0 2 CO chemical CO induces the dissociation of the haem-mediated dimer of PGRMC1 by interfering with the haem-stacking interface via formation of the six-coordinated CO-haem-PGRMC1 complex. RESULTS 35 39 haem chemical CO induces the dissociation of the haem-mediated dimer of PGRMC1 by interfering with the haem-stacking interface via formation of the six-coordinated CO-haem-PGRMC1 complex. RESULTS 49 54 dimer oligomeric_state CO induces the dissociation of the haem-mediated dimer of PGRMC1 by interfering with the haem-stacking interface via formation of the six-coordinated CO-haem-PGRMC1 complex. RESULTS 58 64 PGRMC1 protein CO induces the dissociation of the haem-mediated dimer of PGRMC1 by interfering with the haem-stacking interface via formation of the six-coordinated CO-haem-PGRMC1 complex. RESULTS 89 112 haem-stacking interface site CO induces the dissociation of the haem-mediated dimer of PGRMC1 by interfering with the haem-stacking interface via formation of the six-coordinated CO-haem-PGRMC1 complex. RESULTS 150 164 CO-haem-PGRMC1 complex_assembly CO induces the dissociation of the haem-mediated dimer of PGRMC1 by interfering with the haem-stacking interface via formation of the six-coordinated CO-haem-PGRMC1 complex. RESULTS 81 87 PGRMC1 protein Such a dynamic structural regulation led us to further examine the regulation of PGRMC1 functions in cancer cells. RESULTS 0 6 PGRMC1 protein PGRMC1 dimerization is required for binding to EGFR RESULTS 7 19 dimerization oligomeric_state PGRMC1 dimerization is required for binding to EGFR RESULTS 47 51 EGFR protein_type PGRMC1 dimerization is required for binding to EGFR RESULTS 8 14 PGRMC1 protein Because PGRMC1 is known to interact with EGFR and to accelerate tumour progression, we examined the effect of haem-dependent dimerization of PGRMC1 on its interaction with EGFR by using purified proteins. RESULTS 41 45 EGFR protein_type Because PGRMC1 is known to interact with EGFR and to accelerate tumour progression, we examined the effect of haem-dependent dimerization of PGRMC1 on its interaction with EGFR by using purified proteins. RESULTS 110 114 haem chemical Because PGRMC1 is known to interact with EGFR and to accelerate tumour progression, we examined the effect of haem-dependent dimerization of PGRMC1 on its interaction with EGFR by using purified proteins. RESULTS 125 137 dimerization oligomeric_state Because PGRMC1 is known to interact with EGFR and to accelerate tumour progression, we examined the effect of haem-dependent dimerization of PGRMC1 on its interaction with EGFR by using purified proteins. RESULTS 141 147 PGRMC1 protein Because PGRMC1 is known to interact with EGFR and to accelerate tumour progression, we examined the effect of haem-dependent dimerization of PGRMC1 on its interaction with EGFR by using purified proteins. RESULTS 172 176 EGFR protein_type Because PGRMC1 is known to interact with EGFR and to accelerate tumour progression, we examined the effect of haem-dependent dimerization of PGRMC1 on its interaction with EGFR by using purified proteins. RESULTS 25 41 cytosolic domain structure_element As shown in Fig. 4a, the cytosolic domain of wild-type PGRMC1, but not the Y113F mutant, interacted with purified EGFR in a haem-dependent manner. RESULTS 45 54 wild-type protein_state As shown in Fig. 4a, the cytosolic domain of wild-type PGRMC1, but not the Y113F mutant, interacted with purified EGFR in a haem-dependent manner. RESULTS 55 61 PGRMC1 protein As shown in Fig. 4a, the cytosolic domain of wild-type PGRMC1, but not the Y113F mutant, interacted with purified EGFR in a haem-dependent manner. RESULTS 75 80 Y113F mutant As shown in Fig. 4a, the cytosolic domain of wild-type PGRMC1, but not the Y113F mutant, interacted with purified EGFR in a haem-dependent manner. RESULTS 81 87 mutant protein_state As shown in Fig. 4a, the cytosolic domain of wild-type PGRMC1, but not the Y113F mutant, interacted with purified EGFR in a haem-dependent manner. RESULTS 114 118 EGFR protein_type As shown in Fig. 4a, the cytosolic domain of wild-type PGRMC1, but not the Y113F mutant, interacted with purified EGFR in a haem-dependent manner. RESULTS 124 128 haem chemical As shown in Fig. 4a, the cytosolic domain of wild-type PGRMC1, but not the Y113F mutant, interacted with purified EGFR in a haem-dependent manner. RESULTS 38 47 ruthenium chemical This interaction was disrupted by the ruthenium-based CO-releasing molecule, CORM3, but not by RuCl3 as a control reagent (Fig. 4b). RESULTS 54 56 CO chemical This interaction was disrupted by the ruthenium-based CO-releasing molecule, CORM3, but not by RuCl3 as a control reagent (Fig. 4b). RESULTS 77 82 CORM3 chemical This interaction was disrupted by the ruthenium-based CO-releasing molecule, CORM3, but not by RuCl3 as a control reagent (Fig. 4b). RESULTS 95 100 RuCl3 chemical This interaction was disrupted by the ruthenium-based CO-releasing molecule, CORM3, but not by RuCl3 as a control reagent (Fig. 4b). RESULTS 58 64 PGRMC1 protein We further analysed the intracellular interaction between PGRMC1 and EGFR. RESULTS 69 73 EGFR protein_type We further analysed the intracellular interaction between PGRMC1 and EGFR. RESULTS 0 11 FLAG-tagged protein_state FLAG-tagged PGRMC1 ectopically expressed in human colon cancer HCT116 cells was immunoprecipitated with anti-FLAG antibody, and co-immunoprecipitated EGFR and endogenous PGRMC1 binding to FLAG-PGRMC1 were detected by Western blotting (Fig. 4c). RESULTS 12 18 PGRMC1 protein FLAG-tagged PGRMC1 ectopically expressed in human colon cancer HCT116 cells was immunoprecipitated with anti-FLAG antibody, and co-immunoprecipitated EGFR and endogenous PGRMC1 binding to FLAG-PGRMC1 were detected by Western blotting (Fig. 4c). RESULTS 19 40 ectopically expressed experimental_method FLAG-tagged PGRMC1 ectopically expressed in human colon cancer HCT116 cells was immunoprecipitated with anti-FLAG antibody, and co-immunoprecipitated EGFR and endogenous PGRMC1 binding to FLAG-PGRMC1 were detected by Western blotting (Fig. 4c). RESULTS 44 49 human species FLAG-tagged PGRMC1 ectopically expressed in human colon cancer HCT116 cells was immunoprecipitated with anti-FLAG antibody, and co-immunoprecipitated EGFR and endogenous PGRMC1 binding to FLAG-PGRMC1 were detected by Western blotting (Fig. 4c). RESULTS 80 98 immunoprecipitated experimental_method FLAG-tagged PGRMC1 ectopically expressed in human colon cancer HCT116 cells was immunoprecipitated with anti-FLAG antibody, and co-immunoprecipitated EGFR and endogenous PGRMC1 binding to FLAG-PGRMC1 were detected by Western blotting (Fig. 4c). RESULTS 128 149 co-immunoprecipitated experimental_method FLAG-tagged PGRMC1 ectopically expressed in human colon cancer HCT116 cells was immunoprecipitated with anti-FLAG antibody, and co-immunoprecipitated EGFR and endogenous PGRMC1 binding to FLAG-PGRMC1 were detected by Western blotting (Fig. 4c). RESULTS 150 154 EGFR protein_type FLAG-tagged PGRMC1 ectopically expressed in human colon cancer HCT116 cells was immunoprecipitated with anti-FLAG antibody, and co-immunoprecipitated EGFR and endogenous PGRMC1 binding to FLAG-PGRMC1 were detected by Western blotting (Fig. 4c). RESULTS 159 169 endogenous protein_state FLAG-tagged PGRMC1 ectopically expressed in human colon cancer HCT116 cells was immunoprecipitated with anti-FLAG antibody, and co-immunoprecipitated EGFR and endogenous PGRMC1 binding to FLAG-PGRMC1 were detected by Western blotting (Fig. 4c). RESULTS 170 176 PGRMC1 protein FLAG-tagged PGRMC1 ectopically expressed in human colon cancer HCT116 cells was immunoprecipitated with anti-FLAG antibody, and co-immunoprecipitated EGFR and endogenous PGRMC1 binding to FLAG-PGRMC1 were detected by Western blotting (Fig. 4c). RESULTS 193 199 PGRMC1 protein FLAG-tagged PGRMC1 ectopically expressed in human colon cancer HCT116 cells was immunoprecipitated with anti-FLAG antibody, and co-immunoprecipitated EGFR and endogenous PGRMC1 binding to FLAG-PGRMC1 were detected by Western blotting (Fig. 4c). RESULTS 217 233 Western blotting experimental_method FLAG-tagged PGRMC1 ectopically expressed in human colon cancer HCT116 cells was immunoprecipitated with anti-FLAG antibody, and co-immunoprecipitated EGFR and endogenous PGRMC1 binding to FLAG-PGRMC1 were detected by Western blotting (Fig. 4c). RESULTS 4 9 C129S mutant The C129S mutant of PGRMC1 also interacted with endogenous PGRMC1 and EGFR (Supplementary Fig. 16). RESULTS 10 16 mutant protein_state The C129S mutant of PGRMC1 also interacted with endogenous PGRMC1 and EGFR (Supplementary Fig. 16). RESULTS 20 26 PGRMC1 protein The C129S mutant of PGRMC1 also interacted with endogenous PGRMC1 and EGFR (Supplementary Fig. 16). RESULTS 48 58 endogenous protein_state The C129S mutant of PGRMC1 also interacted with endogenous PGRMC1 and EGFR (Supplementary Fig. 16). RESULTS 59 65 PGRMC1 protein The C129S mutant of PGRMC1 also interacted with endogenous PGRMC1 and EGFR (Supplementary Fig. 16). RESULTS 70 74 EGFR protein_type The C129S mutant of PGRMC1 also interacted with endogenous PGRMC1 and EGFR (Supplementary Fig. 16). RESULTS 8 19 FLAG-tagged protein_state Whereas FLAG-tagged wild-type PGRMC1 interacted with endogenous PGRMC1 and EGFR, the Y113F mutant did not. RESULTS 20 29 wild-type protein_state Whereas FLAG-tagged wild-type PGRMC1 interacted with endogenous PGRMC1 and EGFR, the Y113F mutant did not. RESULTS 30 36 PGRMC1 protein Whereas FLAG-tagged wild-type PGRMC1 interacted with endogenous PGRMC1 and EGFR, the Y113F mutant did not. RESULTS 53 63 endogenous protein_state Whereas FLAG-tagged wild-type PGRMC1 interacted with endogenous PGRMC1 and EGFR, the Y113F mutant did not. RESULTS 64 70 PGRMC1 protein Whereas FLAG-tagged wild-type PGRMC1 interacted with endogenous PGRMC1 and EGFR, the Y113F mutant did not. RESULTS 75 79 EGFR protein_type Whereas FLAG-tagged wild-type PGRMC1 interacted with endogenous PGRMC1 and EGFR, the Y113F mutant did not. RESULTS 85 90 Y113F mutant Whereas FLAG-tagged wild-type PGRMC1 interacted with endogenous PGRMC1 and EGFR, the Y113F mutant did not. RESULTS 91 97 mutant protein_state Whereas FLAG-tagged wild-type PGRMC1 interacted with endogenous PGRMC1 and EGFR, the Y113F mutant did not. RESULTS 31 46 succinylacetone chemical We also examined the effect of succinylacetone (SA), an inhibitor of haem biosynthesis (Fig. 4d). RESULTS 48 50 SA chemical We also examined the effect of succinylacetone (SA), an inhibitor of haem biosynthesis (Fig. 4d). RESULTS 69 73 haem chemical We also examined the effect of succinylacetone (SA), an inhibitor of haem biosynthesis (Fig. 4d). RESULTS 13 15 SA chemical As expected, SA significantly reduced PGRMC1 dimerization and its interaction with EGFR (Fig. 4e), indicating that haem-mediated dimerization of PGMRC1 is critical for its binding to EGFR. RESULTS 30 37 reduced protein_state As expected, SA significantly reduced PGRMC1 dimerization and its interaction with EGFR (Fig. 4e), indicating that haem-mediated dimerization of PGMRC1 is critical for its binding to EGFR. RESULTS 38 44 PGRMC1 protein As expected, SA significantly reduced PGRMC1 dimerization and its interaction with EGFR (Fig. 4e), indicating that haem-mediated dimerization of PGMRC1 is critical for its binding to EGFR. RESULTS 45 57 dimerization oligomeric_state As expected, SA significantly reduced PGRMC1 dimerization and its interaction with EGFR (Fig. 4e), indicating that haem-mediated dimerization of PGMRC1 is critical for its binding to EGFR. RESULTS 83 87 EGFR protein_type As expected, SA significantly reduced PGRMC1 dimerization and its interaction with EGFR (Fig. 4e), indicating that haem-mediated dimerization of PGMRC1 is critical for its binding to EGFR. RESULTS 115 119 haem chemical As expected, SA significantly reduced PGRMC1 dimerization and its interaction with EGFR (Fig. 4e), indicating that haem-mediated dimerization of PGMRC1 is critical for its binding to EGFR. RESULTS 129 141 dimerization oligomeric_state As expected, SA significantly reduced PGRMC1 dimerization and its interaction with EGFR (Fig. 4e), indicating that haem-mediated dimerization of PGMRC1 is critical for its binding to EGFR. RESULTS 145 151 PGMRC1 protein As expected, SA significantly reduced PGRMC1 dimerization and its interaction with EGFR (Fig. 4e), indicating that haem-mediated dimerization of PGMRC1 is critical for its binding to EGFR. RESULTS 183 187 EGFR protein_type As expected, SA significantly reduced PGRMC1 dimerization and its interaction with EGFR (Fig. 4e), indicating that haem-mediated dimerization of PGMRC1 is critical for its binding to EGFR. RESULTS 0 6 PGRMC1 protein PGRMC1 dimer facilitates EGFR-mediated cancer growth RESULTS 7 12 dimer oligomeric_state PGRMC1 dimer facilitates EGFR-mediated cancer growth RESULTS 25 29 EGFR protein_type PGRMC1 dimer facilitates EGFR-mediated cancer growth RESULTS 53 59 PGRMC1 protein Next, we investigated the functional significance of PGRMC1 dimerization in EGFR signaling. RESULTS 60 72 dimerization oligomeric_state Next, we investigated the functional significance of PGRMC1 dimerization in EGFR signaling. RESULTS 76 80 EGFR protein_type Next, we investigated the functional significance of PGRMC1 dimerization in EGFR signaling. RESULTS 0 3 EGF protein_type EGF-induced phosphorylations of EGFR and its downstream targets AKT and ERK were decreased by PGRMC1 knockdown (PGRMC1-KD) (Fig. 4f). RESULTS 12 28 phosphorylations ptm EGF-induced phosphorylations of EGFR and its downstream targets AKT and ERK were decreased by PGRMC1 knockdown (PGRMC1-KD) (Fig. 4f). RESULTS 32 36 EGFR protein_type EGF-induced phosphorylations of EGFR and its downstream targets AKT and ERK were decreased by PGRMC1 knockdown (PGRMC1-KD) (Fig. 4f). RESULTS 64 67 AKT protein_type EGF-induced phosphorylations of EGFR and its downstream targets AKT and ERK were decreased by PGRMC1 knockdown (PGRMC1-KD) (Fig. 4f). RESULTS 72 75 ERK protein_type EGF-induced phosphorylations of EGFR and its downstream targets AKT and ERK were decreased by PGRMC1 knockdown (PGRMC1-KD) (Fig. 4f). RESULTS 94 100 PGRMC1 protein EGF-induced phosphorylations of EGFR and its downstream targets AKT and ERK were decreased by PGRMC1 knockdown (PGRMC1-KD) (Fig. 4f). RESULTS 101 110 knockdown protein_state EGF-induced phosphorylations of EGFR and its downstream targets AKT and ERK were decreased by PGRMC1 knockdown (PGRMC1-KD) (Fig. 4f). RESULTS 112 121 PGRMC1-KD mutant EGF-induced phosphorylations of EGFR and its downstream targets AKT and ERK were decreased by PGRMC1 knockdown (PGRMC1-KD) (Fig. 4f). RESULTS 11 15 EGFR protein_type Similarly, EGFR signaling was suppressed by treatment of HCT116 cells with SA (Fig. 4g) or CORM3 (Fig. 4h). RESULTS 75 77 SA chemical Similarly, EGFR signaling was suppressed by treatment of HCT116 cells with SA (Fig. 4g) or CORM3 (Fig. 4h). RESULTS 91 96 CORM3 chemical Similarly, EGFR signaling was suppressed by treatment of HCT116 cells with SA (Fig. 4g) or CORM3 (Fig. 4h). RESULTS 29 33 haem chemical These results suggested that haem-mediated dimerization of PGRMC1 is critical for EGFR signaling. RESULTS 43 55 dimerization oligomeric_state These results suggested that haem-mediated dimerization of PGRMC1 is critical for EGFR signaling. RESULTS 59 65 PGRMC1 protein These results suggested that haem-mediated dimerization of PGRMC1 is critical for EGFR signaling. RESULTS 82 86 EGFR protein_type These results suggested that haem-mediated dimerization of PGRMC1 is critical for EGFR signaling. RESULTS 39 48 dimerized protein_state To further investigate the role of the dimerized form of PGRMC1 in cancer proliferation, we performed PGRMC1 knockdown-rescue experiments using FLAG-tagged wild-type and Y113F PGRMC1 expression vectors, in which silent mutations were introduced into the nucleotide sequence targeted by shRNA (Fig. 5a). RESULTS 57 63 PGRMC1 protein To further investigate the role of the dimerized form of PGRMC1 in cancer proliferation, we performed PGRMC1 knockdown-rescue experiments using FLAG-tagged wild-type and Y113F PGRMC1 expression vectors, in which silent mutations were introduced into the nucleotide sequence targeted by shRNA (Fig. 5a). RESULTS 102 108 PGRMC1 protein To further investigate the role of the dimerized form of PGRMC1 in cancer proliferation, we performed PGRMC1 knockdown-rescue experiments using FLAG-tagged wild-type and Y113F PGRMC1 expression vectors, in which silent mutations were introduced into the nucleotide sequence targeted by shRNA (Fig. 5a). RESULTS 109 137 knockdown-rescue experiments experimental_method To further investigate the role of the dimerized form of PGRMC1 in cancer proliferation, we performed PGRMC1 knockdown-rescue experiments using FLAG-tagged wild-type and Y113F PGRMC1 expression vectors, in which silent mutations were introduced into the nucleotide sequence targeted by shRNA (Fig. 5a). RESULTS 144 155 FLAG-tagged protein_state To further investigate the role of the dimerized form of PGRMC1 in cancer proliferation, we performed PGRMC1 knockdown-rescue experiments using FLAG-tagged wild-type and Y113F PGRMC1 expression vectors, in which silent mutations were introduced into the nucleotide sequence targeted by shRNA (Fig. 5a). RESULTS 156 165 wild-type protein_state To further investigate the role of the dimerized form of PGRMC1 in cancer proliferation, we performed PGRMC1 knockdown-rescue experiments using FLAG-tagged wild-type and Y113F PGRMC1 expression vectors, in which silent mutations were introduced into the nucleotide sequence targeted by shRNA (Fig. 5a). RESULTS 170 175 Y113F mutant To further investigate the role of the dimerized form of PGRMC1 in cancer proliferation, we performed PGRMC1 knockdown-rescue experiments using FLAG-tagged wild-type and Y113F PGRMC1 expression vectors, in which silent mutations were introduced into the nucleotide sequence targeted by shRNA (Fig. 5a). RESULTS 176 182 PGRMC1 protein To further investigate the role of the dimerized form of PGRMC1 in cancer proliferation, we performed PGRMC1 knockdown-rescue experiments using FLAG-tagged wild-type and Y113F PGRMC1 expression vectors, in which silent mutations were introduced into the nucleotide sequence targeted by shRNA (Fig. 5a). RESULTS 183 201 expression vectors experimental_method To further investigate the role of the dimerized form of PGRMC1 in cancer proliferation, we performed PGRMC1 knockdown-rescue experiments using FLAG-tagged wild-type and Y113F PGRMC1 expression vectors, in which silent mutations were introduced into the nucleotide sequence targeted by shRNA (Fig. 5a). RESULTS 212 228 silent mutations experimental_method To further investigate the role of the dimerized form of PGRMC1 in cancer proliferation, we performed PGRMC1 knockdown-rescue experiments using FLAG-tagged wild-type and Y113F PGRMC1 expression vectors, in which silent mutations were introduced into the nucleotide sequence targeted by shRNA (Fig. 5a). RESULTS 234 244 introduced experimental_method To further investigate the role of the dimerized form of PGRMC1 in cancer proliferation, we performed PGRMC1 knockdown-rescue experiments using FLAG-tagged wild-type and Y113F PGRMC1 expression vectors, in which silent mutations were introduced into the nucleotide sequence targeted by shRNA (Fig. 5a). RESULTS 286 291 shRNA chemical To further investigate the role of the dimerized form of PGRMC1 in cancer proliferation, we performed PGRMC1 knockdown-rescue experiments using FLAG-tagged wild-type and Y113F PGRMC1 expression vectors, in which silent mutations were introduced into the nucleotide sequence targeted by shRNA (Fig. 5a). RESULTS 56 69 knocking down experimental_method While proliferation of HCT116 cells was not affected by knocking down PGRMC1, PGRMC1-KD cells were more sensitive to the EGFR inhibitor erlotinib than control HCT116 cells, and the knockdown effect was reversed by co-expression of shRNA-resistant wild-type PGRMC1 but not of the Y113F mutant (Fig. 5b). RESULTS 70 76 PGRMC1 protein While proliferation of HCT116 cells was not affected by knocking down PGRMC1, PGRMC1-KD cells were more sensitive to the EGFR inhibitor erlotinib than control HCT116 cells, and the knockdown effect was reversed by co-expression of shRNA-resistant wild-type PGRMC1 but not of the Y113F mutant (Fig. 5b). RESULTS 78 87 PGRMC1-KD mutant While proliferation of HCT116 cells was not affected by knocking down PGRMC1, PGRMC1-KD cells were more sensitive to the EGFR inhibitor erlotinib than control HCT116 cells, and the knockdown effect was reversed by co-expression of shRNA-resistant wild-type PGRMC1 but not of the Y113F mutant (Fig. 5b). RESULTS 121 125 EGFR protein_type While proliferation of HCT116 cells was not affected by knocking down PGRMC1, PGRMC1-KD cells were more sensitive to the EGFR inhibitor erlotinib than control HCT116 cells, and the knockdown effect was reversed by co-expression of shRNA-resistant wild-type PGRMC1 but not of the Y113F mutant (Fig. 5b). RESULTS 136 145 erlotinib chemical While proliferation of HCT116 cells was not affected by knocking down PGRMC1, PGRMC1-KD cells were more sensitive to the EGFR inhibitor erlotinib than control HCT116 cells, and the knockdown effect was reversed by co-expression of shRNA-resistant wild-type PGRMC1 but not of the Y113F mutant (Fig. 5b). RESULTS 214 227 co-expression experimental_method While proliferation of HCT116 cells was not affected by knocking down PGRMC1, PGRMC1-KD cells were more sensitive to the EGFR inhibitor erlotinib than control HCT116 cells, and the knockdown effect was reversed by co-expression of shRNA-resistant wild-type PGRMC1 but not of the Y113F mutant (Fig. 5b). RESULTS 231 246 shRNA-resistant protein_state While proliferation of HCT116 cells was not affected by knocking down PGRMC1, PGRMC1-KD cells were more sensitive to the EGFR inhibitor erlotinib than control HCT116 cells, and the knockdown effect was reversed by co-expression of shRNA-resistant wild-type PGRMC1 but not of the Y113F mutant (Fig. 5b). RESULTS 247 256 wild-type protein_state While proliferation of HCT116 cells was not affected by knocking down PGRMC1, PGRMC1-KD cells were more sensitive to the EGFR inhibitor erlotinib than control HCT116 cells, and the knockdown effect was reversed by co-expression of shRNA-resistant wild-type PGRMC1 but not of the Y113F mutant (Fig. 5b). RESULTS 257 263 PGRMC1 protein While proliferation of HCT116 cells was not affected by knocking down PGRMC1, PGRMC1-KD cells were more sensitive to the EGFR inhibitor erlotinib than control HCT116 cells, and the knockdown effect was reversed by co-expression of shRNA-resistant wild-type PGRMC1 but not of the Y113F mutant (Fig. 5b). RESULTS 279 284 Y113F mutant While proliferation of HCT116 cells was not affected by knocking down PGRMC1, PGRMC1-KD cells were more sensitive to the EGFR inhibitor erlotinib than control HCT116 cells, and the knockdown effect was reversed by co-expression of shRNA-resistant wild-type PGRMC1 but not of the Y113F mutant (Fig. 5b). RESULTS 285 291 mutant protein_state While proliferation of HCT116 cells was not affected by knocking down PGRMC1, PGRMC1-KD cells were more sensitive to the EGFR inhibitor erlotinib than control HCT116 cells, and the knockdown effect was reversed by co-expression of shRNA-resistant wild-type PGRMC1 but not of the Y113F mutant (Fig. 5b). RESULTS 46 52 shRNAs chemical Chemosensitivity enhancement by two different shRNAs to PGRMC1 was seen also in HCT116 cells and human hepatoma HuH7 cells (Supplementary Fig. 17). RESULTS 56 62 PGRMC1 protein Chemosensitivity enhancement by two different shRNAs to PGRMC1 was seen also in HCT116 cells and human hepatoma HuH7 cells (Supplementary Fig. 17). RESULTS 97 102 human species Chemosensitivity enhancement by two different shRNAs to PGRMC1 was seen also in HCT116 cells and human hepatoma HuH7 cells (Supplementary Fig. 17). RESULTS 13 22 PGRMC1-KD mutant Furthermore, PGRMC1-KD inhibited spheroid formation of HCT116 cells in culture, and this inhibition was reversed by co-expression of wild-type PGRMC1 but not of the Y113F mutant (Fig. 5c and Supplementary Fig. 18). RESULTS 116 129 co-expression experimental_method Furthermore, PGRMC1-KD inhibited spheroid formation of HCT116 cells in culture, and this inhibition was reversed by co-expression of wild-type PGRMC1 but not of the Y113F mutant (Fig. 5c and Supplementary Fig. 18). RESULTS 133 142 wild-type protein_state Furthermore, PGRMC1-KD inhibited spheroid formation of HCT116 cells in culture, and this inhibition was reversed by co-expression of wild-type PGRMC1 but not of the Y113F mutant (Fig. 5c and Supplementary Fig. 18). RESULTS 143 149 PGRMC1 protein Furthermore, PGRMC1-KD inhibited spheroid formation of HCT116 cells in culture, and this inhibition was reversed by co-expression of wild-type PGRMC1 but not of the Y113F mutant (Fig. 5c and Supplementary Fig. 18). RESULTS 165 170 Y113F mutant Furthermore, PGRMC1-KD inhibited spheroid formation of HCT116 cells in culture, and this inhibition was reversed by co-expression of wild-type PGRMC1 but not of the Y113F mutant (Fig. 5c and Supplementary Fig. 18). RESULTS 171 177 mutant protein_state Furthermore, PGRMC1-KD inhibited spheroid formation of HCT116 cells in culture, and this inhibition was reversed by co-expression of wild-type PGRMC1 but not of the Y113F mutant (Fig. 5c and Supplementary Fig. 18). RESULTS 6 12 PGRMC1 protein Thus, PGRMC1 dimerization is important for cancer cell proliferation and chemoresistance. RESULTS 13 25 dimerization oligomeric_state Thus, PGRMC1 dimerization is important for cancer cell proliferation and chemoresistance. RESULTS 24 30 PGRMC1 protein We examined the role of PGRMC1 in metastatic progression by xenograft transplantation assays using super-immunodeficient NOD/scid/γnull (NOG) mice. RESULTS 60 92 xenograft transplantation assays experimental_method We examined the role of PGRMC1 in metastatic progression by xenograft transplantation assays using super-immunodeficient NOD/scid/γnull (NOG) mice. RESULTS 15 41 intra-splenic implantation experimental_method Ten days after intra-splenic implantation of HCT116 cells that were genetically tagged with a fluorescent protein Venus, the group implanted with PGRMC1-KD cells showed a significant decrease of liver metastasis in comparison with the control group (Fig. 5d). RESULTS 146 155 PGRMC1-KD mutant Ten days after intra-splenic implantation of HCT116 cells that were genetically tagged with a fluorescent protein Venus, the group implanted with PGRMC1-KD cells showed a significant decrease of liver metastasis in comparison with the control group (Fig. 5d). RESULTS 15 21 PGRMC1 protein Interaction of PGRMC1 dimer with cytochromes P450 RESULTS 22 27 dimer oligomeric_state Interaction of PGRMC1 dimer with cytochromes P450 RESULTS 33 49 cytochromes P450 protein_type Interaction of PGRMC1 dimer with cytochromes P450 RESULTS 6 12 PGRMC1 protein Since PGRMC1 has been shown to interact with cytochromes P450 (ref), we investigated whether the haem-mediated dimerization of PGRMC1 is necessary for their interactions. RESULTS 45 61 cytochromes P450 protein_type Since PGRMC1 has been shown to interact with cytochromes P450 (ref), we investigated whether the haem-mediated dimerization of PGRMC1 is necessary for their interactions. RESULTS 97 101 haem chemical Since PGRMC1 has been shown to interact with cytochromes P450 (ref), we investigated whether the haem-mediated dimerization of PGRMC1 is necessary for their interactions. RESULTS 111 123 dimerization oligomeric_state Since PGRMC1 has been shown to interact with cytochromes P450 (ref), we investigated whether the haem-mediated dimerization of PGRMC1 is necessary for their interactions. RESULTS 127 133 PGRMC1 protein Since PGRMC1 has been shown to interact with cytochromes P450 (ref), we investigated whether the haem-mediated dimerization of PGRMC1 is necessary for their interactions. RESULTS 12 18 CYP1A2 protein Recombinant CYP1A2 and CYP3A4 including a microsomal formulation containing cytochrome b5 and cytochrome P450 reductase, drug-metabolizing cytochromes P450, interacted with wild-type PGRMC1, but not with the Y113F mutant, in a haem-dependent manner (Fig. 6a,b). RESULTS 23 29 CYP3A4 protein Recombinant CYP1A2 and CYP3A4 including a microsomal formulation containing cytochrome b5 and cytochrome P450 reductase, drug-metabolizing cytochromes P450, interacted with wild-type PGRMC1, but not with the Y113F mutant, in a haem-dependent manner (Fig. 6a,b). RESULTS 76 89 cytochrome b5 protein_type Recombinant CYP1A2 and CYP3A4 including a microsomal formulation containing cytochrome b5 and cytochrome P450 reductase, drug-metabolizing cytochromes P450, interacted with wild-type PGRMC1, but not with the Y113F mutant, in a haem-dependent manner (Fig. 6a,b). RESULTS 94 119 cytochrome P450 reductase protein Recombinant CYP1A2 and CYP3A4 including a microsomal formulation containing cytochrome b5 and cytochrome P450 reductase, drug-metabolizing cytochromes P450, interacted with wild-type PGRMC1, but not with the Y113F mutant, in a haem-dependent manner (Fig. 6a,b). RESULTS 139 155 cytochromes P450 protein_type Recombinant CYP1A2 and CYP3A4 including a microsomal formulation containing cytochrome b5 and cytochrome P450 reductase, drug-metabolizing cytochromes P450, interacted with wild-type PGRMC1, but not with the Y113F mutant, in a haem-dependent manner (Fig. 6a,b). RESULTS 173 182 wild-type protein_state Recombinant CYP1A2 and CYP3A4 including a microsomal formulation containing cytochrome b5 and cytochrome P450 reductase, drug-metabolizing cytochromes P450, interacted with wild-type PGRMC1, but not with the Y113F mutant, in a haem-dependent manner (Fig. 6a,b). RESULTS 183 189 PGRMC1 protein Recombinant CYP1A2 and CYP3A4 including a microsomal formulation containing cytochrome b5 and cytochrome P450 reductase, drug-metabolizing cytochromes P450, interacted with wild-type PGRMC1, but not with the Y113F mutant, in a haem-dependent manner (Fig. 6a,b). RESULTS 208 213 Y113F mutant Recombinant CYP1A2 and CYP3A4 including a microsomal formulation containing cytochrome b5 and cytochrome P450 reductase, drug-metabolizing cytochromes P450, interacted with wild-type PGRMC1, but not with the Y113F mutant, in a haem-dependent manner (Fig. 6a,b). RESULTS 214 220 mutant protein_state Recombinant CYP1A2 and CYP3A4 including a microsomal formulation containing cytochrome b5 and cytochrome P450 reductase, drug-metabolizing cytochromes P450, interacted with wild-type PGRMC1, but not with the Y113F mutant, in a haem-dependent manner (Fig. 6a,b). RESULTS 227 231 haem chemical Recombinant CYP1A2 and CYP3A4 including a microsomal formulation containing cytochrome b5 and cytochrome P450 reductase, drug-metabolizing cytochromes P450, interacted with wild-type PGRMC1, but not with the Y113F mutant, in a haem-dependent manner (Fig. 6a,b). RESULTS 29 35 PGRMC1 protein Moreover, the interaction of PGRMC1 with CYP1A2 was blocked by CORM3 under reducing conditions (Fig. 6c), indicating that PGRMC1 dimerization is necessary for its interaction with cytochromes P450. RESULTS 41 47 CYP1A2 protein Moreover, the interaction of PGRMC1 with CYP1A2 was blocked by CORM3 under reducing conditions (Fig. 6c), indicating that PGRMC1 dimerization is necessary for its interaction with cytochromes P450. RESULTS 63 68 CORM3 chemical Moreover, the interaction of PGRMC1 with CYP1A2 was blocked by CORM3 under reducing conditions (Fig. 6c), indicating that PGRMC1 dimerization is necessary for its interaction with cytochromes P450. RESULTS 122 128 PGRMC1 protein Moreover, the interaction of PGRMC1 with CYP1A2 was blocked by CORM3 under reducing conditions (Fig. 6c), indicating that PGRMC1 dimerization is necessary for its interaction with cytochromes P450. RESULTS 129 141 dimerization oligomeric_state Moreover, the interaction of PGRMC1 with CYP1A2 was blocked by CORM3 under reducing conditions (Fig. 6c), indicating that PGRMC1 dimerization is necessary for its interaction with cytochromes P450. RESULTS 180 196 cytochromes P450 protein_type Moreover, the interaction of PGRMC1 with CYP1A2 was blocked by CORM3 under reducing conditions (Fig. 6c), indicating that PGRMC1 dimerization is necessary for its interaction with cytochromes P450. RESULTS 0 11 Doxorubicin chemical Doxorubicin is an anti-cancer reagent that is metabolized into inactive doxorubicinol by CYP2D6 and CYP3A4 (Fig. 6d). RESULTS 72 85 doxorubicinol chemical Doxorubicin is an anti-cancer reagent that is metabolized into inactive doxorubicinol by CYP2D6 and CYP3A4 (Fig. 6d). RESULTS 89 95 CYP2D6 protein Doxorubicin is an anti-cancer reagent that is metabolized into inactive doxorubicinol by CYP2D6 and CYP3A4 (Fig. 6d). RESULTS 100 106 CYP3A4 protein Doxorubicin is an anti-cancer reagent that is metabolized into inactive doxorubicinol by CYP2D6 and CYP3A4 (Fig. 6d). RESULTS 0 9 PGRMC1-KD mutant PGRMC1-KD significantly suppressed the conversion of doxorubicin to doxorubicinol (Fig. 6d) and increased sensitivity to doxorubicin (Fig. 6e). RESULTS 53 64 doxorubicin chemical PGRMC1-KD significantly suppressed the conversion of doxorubicin to doxorubicinol (Fig. 6d) and increased sensitivity to doxorubicin (Fig. 6e). RESULTS 68 81 doxorubicinol chemical PGRMC1-KD significantly suppressed the conversion of doxorubicin to doxorubicinol (Fig. 6d) and increased sensitivity to doxorubicin (Fig. 6e). RESULTS 121 132 doxorubicin chemical PGRMC1-KD significantly suppressed the conversion of doxorubicin to doxorubicinol (Fig. 6d) and increased sensitivity to doxorubicin (Fig. 6e). RESULTS 9 20 doxorubicin chemical Enhanced doxorubicin sensitivity was modestly but significantly induced by PGRMC1-KD. RESULTS 75 84 PGRMC1-KD mutant Enhanced doxorubicin sensitivity was modestly but significantly induced by PGRMC1-KD. RESULTS 28 41 co-expression experimental_method This effect was reversed by co-expression of the wild-type PGRMC1 but not of the Y113F mutant, suggesting that PGRMC1 enhances doxorubicin resistance of cancer cells by facilitating its degradation via cytochromes P450. RESULTS 49 58 wild-type protein_state This effect was reversed by co-expression of the wild-type PGRMC1 but not of the Y113F mutant, suggesting that PGRMC1 enhances doxorubicin resistance of cancer cells by facilitating its degradation via cytochromes P450. RESULTS 59 65 PGRMC1 protein This effect was reversed by co-expression of the wild-type PGRMC1 but not of the Y113F mutant, suggesting that PGRMC1 enhances doxorubicin resistance of cancer cells by facilitating its degradation via cytochromes P450. RESULTS 81 86 Y113F mutant This effect was reversed by co-expression of the wild-type PGRMC1 but not of the Y113F mutant, suggesting that PGRMC1 enhances doxorubicin resistance of cancer cells by facilitating its degradation via cytochromes P450. RESULTS 87 93 mutant protein_state This effect was reversed by co-expression of the wild-type PGRMC1 but not of the Y113F mutant, suggesting that PGRMC1 enhances doxorubicin resistance of cancer cells by facilitating its degradation via cytochromes P450. RESULTS 111 117 PGRMC1 protein This effect was reversed by co-expression of the wild-type PGRMC1 but not of the Y113F mutant, suggesting that PGRMC1 enhances doxorubicin resistance of cancer cells by facilitating its degradation via cytochromes P450. RESULTS 127 138 doxorubicin chemical This effect was reversed by co-expression of the wild-type PGRMC1 but not of the Y113F mutant, suggesting that PGRMC1 enhances doxorubicin resistance of cancer cells by facilitating its degradation via cytochromes P450. RESULTS 202 218 cytochromes P450 protein_type This effect was reversed by co-expression of the wild-type PGRMC1 but not of the Y113F mutant, suggesting that PGRMC1 enhances doxorubicin resistance of cancer cells by facilitating its degradation via cytochromes P450. RESULTS 53 59 PGRMC1 protein To gain further insight into the interaction between PGRMC1 and cytochromes P450, surface plasmon resonance analyses were conducted using recombinant CYP51 and PGRMC1. RESULTS 64 80 cytochromes P450 protein_type To gain further insight into the interaction between PGRMC1 and cytochromes P450, surface plasmon resonance analyses were conducted using recombinant CYP51 and PGRMC1. RESULTS 82 116 surface plasmon resonance analyses experimental_method To gain further insight into the interaction between PGRMC1 and cytochromes P450, surface plasmon resonance analyses were conducted using recombinant CYP51 and PGRMC1. RESULTS 150 155 CYP51 protein To gain further insight into the interaction between PGRMC1 and cytochromes P450, surface plasmon resonance analyses were conducted using recombinant CYP51 and PGRMC1. RESULTS 160 166 PGRMC1 protein To gain further insight into the interaction between PGRMC1 and cytochromes P450, surface plasmon resonance analyses were conducted using recombinant CYP51 and PGRMC1. RESULTS 48 54 PGRMC1 protein This was based on a previous study showing that PGRMC1 binds to CYP51 and enhances cholesterol biosynthesis by CYP51 (refs). RESULTS 64 69 CYP51 protein This was based on a previous study showing that PGRMC1 binds to CYP51 and enhances cholesterol biosynthesis by CYP51 (refs). RESULTS 111 116 CYP51 protein This was based on a previous study showing that PGRMC1 binds to CYP51 and enhances cholesterol biosynthesis by CYP51 (refs). RESULTS 0 5 CYP51 protein CYP51 interacted with PGRMC1 in a concentration-dependent manner in the presence of haem, but not in its absence (Supplementary Fig. 19), suggesting the requirement for the haem-dependent dimerization of PGRMC1. RESULTS 22 28 PGRMC1 protein CYP51 interacted with PGRMC1 in a concentration-dependent manner in the presence of haem, but not in its absence (Supplementary Fig. 19), suggesting the requirement for the haem-dependent dimerization of PGRMC1. RESULTS 72 83 presence of protein_state CYP51 interacted with PGRMC1 in a concentration-dependent manner in the presence of haem, but not in its absence (Supplementary Fig. 19), suggesting the requirement for the haem-dependent dimerization of PGRMC1. RESULTS 84 88 haem chemical CYP51 interacted with PGRMC1 in a concentration-dependent manner in the presence of haem, but not in its absence (Supplementary Fig. 19), suggesting the requirement for the haem-dependent dimerization of PGRMC1. RESULTS 105 112 absence protein_state CYP51 interacted with PGRMC1 in a concentration-dependent manner in the presence of haem, but not in its absence (Supplementary Fig. 19), suggesting the requirement for the haem-dependent dimerization of PGRMC1. RESULTS 173 177 haem chemical CYP51 interacted with PGRMC1 in a concentration-dependent manner in the presence of haem, but not in its absence (Supplementary Fig. 19), suggesting the requirement for the haem-dependent dimerization of PGRMC1. RESULTS 188 200 dimerization oligomeric_state CYP51 interacted with PGRMC1 in a concentration-dependent manner in the presence of haem, but not in its absence (Supplementary Fig. 19), suggesting the requirement for the haem-dependent dimerization of PGRMC1. RESULTS 204 210 PGRMC1 protein CYP51 interacted with PGRMC1 in a concentration-dependent manner in the presence of haem, but not in its absence (Supplementary Fig. 19), suggesting the requirement for the haem-dependent dimerization of PGRMC1. RESULTS 4 6 Kd evidence The Kd value of PGRMC1 binding to CYP51 was in a micromolar range and comparable with those of other haem proteins, such as cytochrome P450 reductase and neuroglobin/Gαi1 (ref.), suggesting that haem-dependent PGRMC1 interaction with CYP51 is biologically relevant. RESULTS 16 22 PGRMC1 protein The Kd value of PGRMC1 binding to CYP51 was in a micromolar range and comparable with those of other haem proteins, such as cytochrome P450 reductase and neuroglobin/Gαi1 (ref.), suggesting that haem-dependent PGRMC1 interaction with CYP51 is biologically relevant. RESULTS 34 39 CYP51 protein The Kd value of PGRMC1 binding to CYP51 was in a micromolar range and comparable with those of other haem proteins, such as cytochrome P450 reductase and neuroglobin/Gαi1 (ref.), suggesting that haem-dependent PGRMC1 interaction with CYP51 is biologically relevant. RESULTS 101 105 haem chemical The Kd value of PGRMC1 binding to CYP51 was in a micromolar range and comparable with those of other haem proteins, such as cytochrome P450 reductase and neuroglobin/Gαi1 (ref.), suggesting that haem-dependent PGRMC1 interaction with CYP51 is biologically relevant. RESULTS 124 149 cytochrome P450 reductase protein The Kd value of PGRMC1 binding to CYP51 was in a micromolar range and comparable with those of other haem proteins, such as cytochrome P450 reductase and neuroglobin/Gαi1 (ref.), suggesting that haem-dependent PGRMC1 interaction with CYP51 is biologically relevant. RESULTS 154 165 neuroglobin protein The Kd value of PGRMC1 binding to CYP51 was in a micromolar range and comparable with those of other haem proteins, such as cytochrome P450 reductase and neuroglobin/Gαi1 (ref.), suggesting that haem-dependent PGRMC1 interaction with CYP51 is biologically relevant. RESULTS 166 170 Gαi1 protein The Kd value of PGRMC1 binding to CYP51 was in a micromolar range and comparable with those of other haem proteins, such as cytochrome P450 reductase and neuroglobin/Gαi1 (ref.), suggesting that haem-dependent PGRMC1 interaction with CYP51 is biologically relevant. RESULTS 195 199 haem chemical The Kd value of PGRMC1 binding to CYP51 was in a micromolar range and comparable with those of other haem proteins, such as cytochrome P450 reductase and neuroglobin/Gαi1 (ref.), suggesting that haem-dependent PGRMC1 interaction with CYP51 is biologically relevant. RESULTS 210 216 PGRMC1 protein The Kd value of PGRMC1 binding to CYP51 was in a micromolar range and comparable with those of other haem proteins, such as cytochrome P450 reductase and neuroglobin/Gαi1 (ref.), suggesting that haem-dependent PGRMC1 interaction with CYP51 is biologically relevant. RESULTS 234 239 CYP51 protein The Kd value of PGRMC1 binding to CYP51 was in a micromolar range and comparable with those of other haem proteins, such as cytochrome P450 reductase and neuroglobin/Gαi1 (ref.), suggesting that haem-dependent PGRMC1 interaction with CYP51 is biologically relevant. RESULTS 30 36 PGRMC1 protein In this study, we showed that PGRMC1 dimerizes by stacking interactions of haem molecules from each monomer. DISCUSS 37 46 dimerizes oligomeric_state In this study, we showed that PGRMC1 dimerizes by stacking interactions of haem molecules from each monomer. DISCUSS 50 71 stacking interactions bond_interaction In this study, we showed that PGRMC1 dimerizes by stacking interactions of haem molecules from each monomer. DISCUSS 75 79 haem chemical In this study, we showed that PGRMC1 dimerizes by stacking interactions of haem molecules from each monomer. DISCUSS 100 107 monomer oligomeric_state In this study, we showed that PGRMC1 dimerizes by stacking interactions of haem molecules from each monomer. DISCUSS 37 78 translationally-controlled tumour protein protein_type Recently, Lucas et al. reported that translationally-controlled tumour protein was dimerized by binding with haem, but its structural basis remains unclear. DISCUSS 83 92 dimerized protein_state Recently, Lucas et al. reported that translationally-controlled tumour protein was dimerized by binding with haem, but its structural basis remains unclear. DISCUSS 109 113 haem chemical Recently, Lucas et al. reported that translationally-controlled tumour protein was dimerized by binding with haem, but its structural basis remains unclear. DISCUSS 88 106 haem–haem stacking bond_interaction This is the report showing crystallographic evidence that indicates roles of the direct haem–haem stacking in haem-mediated dimerization in eukaryotes, although a few examples are known in bacteria. DISCUSS 110 114 haem chemical This is the report showing crystallographic evidence that indicates roles of the direct haem–haem stacking in haem-mediated dimerization in eukaryotes, although a few examples are known in bacteria. DISCUSS 124 136 dimerization oligomeric_state This is the report showing crystallographic evidence that indicates roles of the direct haem–haem stacking in haem-mediated dimerization in eukaryotes, although a few examples are known in bacteria. DISCUSS 140 150 eukaryotes taxonomy_domain This is the report showing crystallographic evidence that indicates roles of the direct haem–haem stacking in haem-mediated dimerization in eukaryotes, although a few examples are known in bacteria. DISCUSS 189 197 bacteria taxonomy_domain This is the report showing crystallographic evidence that indicates roles of the direct haem–haem stacking in haem-mediated dimerization in eukaryotes, although a few examples are known in bacteria. DISCUSS 0 19 Sequence alignments experimental_method Sequence alignments show that haem-binding residues (Tyr113, Tyr107, Lys163 and Tyr164) in PGRMC1 are conserved among MAPR proteins (Supplementary Fig. 5). DISCUSS 30 51 haem-binding residues site Sequence alignments show that haem-binding residues (Tyr113, Tyr107, Lys163 and Tyr164) in PGRMC1 are conserved among MAPR proteins (Supplementary Fig. 5). DISCUSS 53 59 Tyr113 residue_name_number Sequence alignments show that haem-binding residues (Tyr113, Tyr107, Lys163 and Tyr164) in PGRMC1 are conserved among MAPR proteins (Supplementary Fig. 5). DISCUSS 61 67 Tyr107 residue_name_number Sequence alignments show that haem-binding residues (Tyr113, Tyr107, Lys163 and Tyr164) in PGRMC1 are conserved among MAPR proteins (Supplementary Fig. 5). DISCUSS 69 75 Lys163 residue_name_number Sequence alignments show that haem-binding residues (Tyr113, Tyr107, Lys163 and Tyr164) in PGRMC1 are conserved among MAPR proteins (Supplementary Fig. 5). DISCUSS 80 86 Tyr164 residue_name_number Sequence alignments show that haem-binding residues (Tyr113, Tyr107, Lys163 and Tyr164) in PGRMC1 are conserved among MAPR proteins (Supplementary Fig. 5). DISCUSS 91 97 PGRMC1 protein Sequence alignments show that haem-binding residues (Tyr113, Tyr107, Lys163 and Tyr164) in PGRMC1 are conserved among MAPR proteins (Supplementary Fig. 5). DISCUSS 102 111 conserved protein_state Sequence alignments show that haem-binding residues (Tyr113, Tyr107, Lys163 and Tyr164) in PGRMC1 are conserved among MAPR proteins (Supplementary Fig. 5). DISCUSS 118 122 MAPR protein_type Sequence alignments show that haem-binding residues (Tyr113, Tyr107, Lys163 and Tyr164) in PGRMC1 are conserved among MAPR proteins (Supplementary Fig. 5). DISCUSS 26 30 Y113 residue_name_number In the current study, the Y113 residue plays a crucial role for the haem-dependent dimerization of PGRMC1 and resultant regulation of cancer proliferation and chemoresistance (Figs 5c and 6e). DISCUSS 68 72 haem chemical In the current study, the Y113 residue plays a crucial role for the haem-dependent dimerization of PGRMC1 and resultant regulation of cancer proliferation and chemoresistance (Figs 5c and 6e). DISCUSS 83 95 dimerization oligomeric_state In the current study, the Y113 residue plays a crucial role for the haem-dependent dimerization of PGRMC1 and resultant regulation of cancer proliferation and chemoresistance (Figs 5c and 6e). DISCUSS 99 105 PGRMC1 protein In the current study, the Y113 residue plays a crucial role for the haem-dependent dimerization of PGRMC1 and resultant regulation of cancer proliferation and chemoresistance (Figs 5c and 6e). DISCUSS 10 14 Y113 residue_name_number Since the Y113 residue is involved in the putative consensus motif of phosphorylation by tyrosine kinases such as Abl and Lck, we investigated whether phosphorylated Y113 is present in HCT116 cells by ESI-MS analysis. DISCUSS 51 66 consensus motif structure_element Since the Y113 residue is involved in the putative consensus motif of phosphorylation by tyrosine kinases such as Abl and Lck, we investigated whether phosphorylated Y113 is present in HCT116 cells by ESI-MS analysis. DISCUSS 70 85 phosphorylation ptm Since the Y113 residue is involved in the putative consensus motif of phosphorylation by tyrosine kinases such as Abl and Lck, we investigated whether phosphorylated Y113 is present in HCT116 cells by ESI-MS analysis. DISCUSS 89 105 tyrosine kinases protein_type Since the Y113 residue is involved in the putative consensus motif of phosphorylation by tyrosine kinases such as Abl and Lck, we investigated whether phosphorylated Y113 is present in HCT116 cells by ESI-MS analysis. DISCUSS 114 117 Abl protein_type Since the Y113 residue is involved in the putative consensus motif of phosphorylation by tyrosine kinases such as Abl and Lck, we investigated whether phosphorylated Y113 is present in HCT116 cells by ESI-MS analysis. DISCUSS 122 125 Lck protein_type Since the Y113 residue is involved in the putative consensus motif of phosphorylation by tyrosine kinases such as Abl and Lck, we investigated whether phosphorylated Y113 is present in HCT116 cells by ESI-MS analysis. DISCUSS 151 165 phosphorylated protein_state Since the Y113 residue is involved in the putative consensus motif of phosphorylation by tyrosine kinases such as Abl and Lck, we investigated whether phosphorylated Y113 is present in HCT116 cells by ESI-MS analysis. DISCUSS 166 170 Y113 residue_name_number Since the Y113 residue is involved in the putative consensus motif of phosphorylation by tyrosine kinases such as Abl and Lck, we investigated whether phosphorylated Y113 is present in HCT116 cells by ESI-MS analysis. DISCUSS 201 207 ESI-MS experimental_method Since the Y113 residue is involved in the putative consensus motif of phosphorylation by tyrosine kinases such as Abl and Lck, we investigated whether phosphorylated Y113 is present in HCT116 cells by ESI-MS analysis. DISCUSS 38 44 PGRMC1 protein Recently, Peluso et al. reported that PGRMC1 binds to PGRMC2, suggesting that MAPR family members may also undergo haem-mediated heterodimerization. DISCUSS 54 60 PGRMC2 protein Recently, Peluso et al. reported that PGRMC1 binds to PGRMC2, suggesting that MAPR family members may also undergo haem-mediated heterodimerization. DISCUSS 78 82 MAPR protein_type Recently, Peluso et al. reported that PGRMC1 binds to PGRMC2, suggesting that MAPR family members may also undergo haem-mediated heterodimerization. DISCUSS 115 119 haem chemical Recently, Peluso et al. reported that PGRMC1 binds to PGRMC2, suggesting that MAPR family members may also undergo haem-mediated heterodimerization. DISCUSS 19 23 haem chemical We showed that the haem-mediated dimer of PGRMC1 enables interaction with different subclasses of cytochromes P450 (CYP) (Fig. 6). DISCUSS 33 38 dimer oligomeric_state We showed that the haem-mediated dimer of PGRMC1 enables interaction with different subclasses of cytochromes P450 (CYP) (Fig. 6). DISCUSS 42 48 PGRMC1 protein We showed that the haem-mediated dimer of PGRMC1 enables interaction with different subclasses of cytochromes P450 (CYP) (Fig. 6). DISCUSS 98 114 cytochromes P450 protein_type We showed that the haem-mediated dimer of PGRMC1 enables interaction with different subclasses of cytochromes P450 (CYP) (Fig. 6). DISCUSS 116 119 CYP protein_type We showed that the haem-mediated dimer of PGRMC1 enables interaction with different subclasses of cytochromes P450 (CYP) (Fig. 6). DISCUSS 21 27 PGRMC1 protein While the effects of PGRMC1 on cholesterol synthesis mediated by CYP51 have been well documented in yeast and human cells, it has not been clear whether drug-metabolizing CYP activities are regulated by PGRMC1. DISCUSS 65 70 CYP51 protein While the effects of PGRMC1 on cholesterol synthesis mediated by CYP51 have been well documented in yeast and human cells, it has not been clear whether drug-metabolizing CYP activities are regulated by PGRMC1. DISCUSS 100 105 yeast taxonomy_domain While the effects of PGRMC1 on cholesterol synthesis mediated by CYP51 have been well documented in yeast and human cells, it has not been clear whether drug-metabolizing CYP activities are regulated by PGRMC1. DISCUSS 110 115 human species While the effects of PGRMC1 on cholesterol synthesis mediated by CYP51 have been well documented in yeast and human cells, it has not been clear whether drug-metabolizing CYP activities are regulated by PGRMC1. DISCUSS 171 174 CYP protein_type While the effects of PGRMC1 on cholesterol synthesis mediated by CYP51 have been well documented in yeast and human cells, it has not been clear whether drug-metabolizing CYP activities are regulated by PGRMC1. DISCUSS 203 209 PGRMC1 protein While the effects of PGRMC1 on cholesterol synthesis mediated by CYP51 have been well documented in yeast and human cells, it has not been clear whether drug-metabolizing CYP activities are regulated by PGRMC1. DISCUSS 42 48 PGRMC1 protein Szczesna-Skorupa and Kemper reported that PGRMC1 exhibited an inhibitory effect on CYP3A4 drug metabolizing activity by competitively binding with cytochrome P450 reductase (CPR) in HEK293 or HepG2 cells. DISCUSS 83 89 CYP3A4 protein Szczesna-Skorupa and Kemper reported that PGRMC1 exhibited an inhibitory effect on CYP3A4 drug metabolizing activity by competitively binding with cytochrome P450 reductase (CPR) in HEK293 or HepG2 cells. DISCUSS 147 172 cytochrome P450 reductase protein Szczesna-Skorupa and Kemper reported that PGRMC1 exhibited an inhibitory effect on CYP3A4 drug metabolizing activity by competitively binding with cytochrome P450 reductase (CPR) in HEK293 or HepG2 cells. DISCUSS 174 177 CPR protein Szczesna-Skorupa and Kemper reported that PGRMC1 exhibited an inhibitory effect on CYP3A4 drug metabolizing activity by competitively binding with cytochrome P450 reductase (CPR) in HEK293 or HepG2 cells. DISCUSS 44 50 PGRMC1 protein On the other hand, Oda et al. reported that PGRMC1 had no effect to CYP2E1 and CYP3A4 activities in HepG2 cell. DISCUSS 68 74 CYP2E1 protein On the other hand, Oda et al. reported that PGRMC1 had no effect to CYP2E1 and CYP3A4 activities in HepG2 cell. DISCUSS 79 85 CYP3A4 protein On the other hand, Oda et al. reported that PGRMC1 had no effect to CYP2E1 and CYP3A4 activities in HepG2 cell. DISCUSS 33 39 PGRMC1 protein Several other groups showed that PGRMC1 enhanced chemoresistance in several cancer cells such as uterine sarcoma, breast cancer, endometrial tumour and ovarian cancer; however, no evidence of PGRMC1-dependent regulation of CYP activity was provided. DISCUSS 192 198 PGRMC1 protein Several other groups showed that PGRMC1 enhanced chemoresistance in several cancer cells such as uterine sarcoma, breast cancer, endometrial tumour and ovarian cancer; however, no evidence of PGRMC1-dependent regulation of CYP activity was provided. DISCUSS 223 226 CYP protein_type Several other groups showed that PGRMC1 enhanced chemoresistance in several cancer cells such as uterine sarcoma, breast cancer, endometrial tumour and ovarian cancer; however, no evidence of PGRMC1-dependent regulation of CYP activity was provided. DISCUSS 24 30 PGRMC1 protein Our results showed that PGRMC1 contributes to enhancement of the doxorubicin metabolism, which is mediated by CYP2D6 or CYP3A4 in human colon cancer HCT116 cells (Fig. 6d). DISCUSS 65 76 doxorubicin chemical Our results showed that PGRMC1 contributes to enhancement of the doxorubicin metabolism, which is mediated by CYP2D6 or CYP3A4 in human colon cancer HCT116 cells (Fig. 6d). DISCUSS 110 116 CYP2D6 protein Our results showed that PGRMC1 contributes to enhancement of the doxorubicin metabolism, which is mediated by CYP2D6 or CYP3A4 in human colon cancer HCT116 cells (Fig. 6d). DISCUSS 120 126 CYP3A4 protein Our results showed that PGRMC1 contributes to enhancement of the doxorubicin metabolism, which is mediated by CYP2D6 or CYP3A4 in human colon cancer HCT116 cells (Fig. 6d). DISCUSS 130 135 human species Our results showed that PGRMC1 contributes to enhancement of the doxorubicin metabolism, which is mediated by CYP2D6 or CYP3A4 in human colon cancer HCT116 cells (Fig. 6d). DISCUSS 45 48 CYP protein_type While the effects of structural diversity of CYP family proteins and interactions with different xenobiotic substrates should further be examined, the current results suggest that the interaction of drug-metabolizing CYPs with the haem-mediated dimer of PGRMC1 plays a crucial role in regulating their activities. DISCUSS 217 221 CYPs protein_type While the effects of structural diversity of CYP family proteins and interactions with different xenobiotic substrates should further be examined, the current results suggest that the interaction of drug-metabolizing CYPs with the haem-mediated dimer of PGRMC1 plays a crucial role in regulating their activities. DISCUSS 231 235 haem chemical While the effects of structural diversity of CYP family proteins and interactions with different xenobiotic substrates should further be examined, the current results suggest that the interaction of drug-metabolizing CYPs with the haem-mediated dimer of PGRMC1 plays a crucial role in regulating their activities. DISCUSS 245 250 dimer oligomeric_state While the effects of structural diversity of CYP family proteins and interactions with different xenobiotic substrates should further be examined, the current results suggest that the interaction of drug-metabolizing CYPs with the haem-mediated dimer of PGRMC1 plays a crucial role in regulating their activities. DISCUSS 254 260 PGRMC1 protein While the effects of structural diversity of CYP family proteins and interactions with different xenobiotic substrates should further be examined, the current results suggest that the interaction of drug-metabolizing CYPs with the haem-mediated dimer of PGRMC1 plays a crucial role in regulating their activities. DISCUSS 15 19 haem chemical We showed that haem-mediated dimerization of PGRMC1 enhances proliferation and chemoresistance of cancer cells through binding to and regulating EGFR and cytochromes P450 (illustrated in Fig. 7). DISCUSS 29 41 dimerization oligomeric_state We showed that haem-mediated dimerization of PGRMC1 enhances proliferation and chemoresistance of cancer cells through binding to and regulating EGFR and cytochromes P450 (illustrated in Fig. 7). DISCUSS 45 51 PGRMC1 protein We showed that haem-mediated dimerization of PGRMC1 enhances proliferation and chemoresistance of cancer cells through binding to and regulating EGFR and cytochromes P450 (illustrated in Fig. 7). DISCUSS 145 149 EGFR protein_type We showed that haem-mediated dimerization of PGRMC1 enhances proliferation and chemoresistance of cancer cells through binding to and regulating EGFR and cytochromes P450 (illustrated in Fig. 7). DISCUSS 154 170 cytochromes P450 protein_type We showed that haem-mediated dimerization of PGRMC1 enhances proliferation and chemoresistance of cancer cells through binding to and regulating EGFR and cytochromes P450 (illustrated in Fig. 7). DISCUSS 10 31 haem-binding affinity evidence Since the haem-binding affinity of PGRMC1 is lower than those of constitutive haem-binding proteins such as myoglobin, PGMRC1 is probably interconverted between apo-monomer and haem-bound dimer forms in response to changes in the intracellular haem concentration. DISCUSS 35 41 PGRMC1 protein Since the haem-binding affinity of PGRMC1 is lower than those of constitutive haem-binding proteins such as myoglobin, PGMRC1 is probably interconverted between apo-monomer and haem-bound dimer forms in response to changes in the intracellular haem concentration. DISCUSS 65 77 constitutive protein_state Since the haem-binding affinity of PGRMC1 is lower than those of constitutive haem-binding proteins such as myoglobin, PGMRC1 is probably interconverted between apo-monomer and haem-bound dimer forms in response to changes in the intracellular haem concentration. DISCUSS 78 99 haem-binding proteins protein_type Since the haem-binding affinity of PGRMC1 is lower than those of constitutive haem-binding proteins such as myoglobin, PGMRC1 is probably interconverted between apo-monomer and haem-bound dimer forms in response to changes in the intracellular haem concentration. DISCUSS 108 117 myoglobin protein Since the haem-binding affinity of PGRMC1 is lower than those of constitutive haem-binding proteins such as myoglobin, PGMRC1 is probably interconverted between apo-monomer and haem-bound dimer forms in response to changes in the intracellular haem concentration. DISCUSS 119 125 PGMRC1 protein Since the haem-binding affinity of PGRMC1 is lower than those of constitutive haem-binding proteins such as myoglobin, PGMRC1 is probably interconverted between apo-monomer and haem-bound dimer forms in response to changes in the intracellular haem concentration. DISCUSS 161 164 apo protein_state Since the haem-binding affinity of PGRMC1 is lower than those of constitutive haem-binding proteins such as myoglobin, PGMRC1 is probably interconverted between apo-monomer and haem-bound dimer forms in response to changes in the intracellular haem concentration. DISCUSS 165 172 monomer oligomeric_state Since the haem-binding affinity of PGRMC1 is lower than those of constitutive haem-binding proteins such as myoglobin, PGMRC1 is probably interconverted between apo-monomer and haem-bound dimer forms in response to changes in the intracellular haem concentration. DISCUSS 177 187 haem-bound protein_state Since the haem-binding affinity of PGRMC1 is lower than those of constitutive haem-binding proteins such as myoglobin, PGMRC1 is probably interconverted between apo-monomer and haem-bound dimer forms in response to changes in the intracellular haem concentration. DISCUSS 188 193 dimer oligomeric_state Since the haem-binding affinity of PGRMC1 is lower than those of constitutive haem-binding proteins such as myoglobin, PGMRC1 is probably interconverted between apo-monomer and haem-bound dimer forms in response to changes in the intracellular haem concentration. DISCUSS 244 248 haem chemical Since the haem-binding affinity of PGRMC1 is lower than those of constitutive haem-binding proteins such as myoglobin, PGMRC1 is probably interconverted between apo-monomer and haem-bound dimer forms in response to changes in the intracellular haem concentration. DISCUSS 67 71 haem chemical Considering microenvironments in and around malignant tumours, the haem concentration in cancer cells is likely to be elevated through multiple mechanisms, such as (i) an increased intake of haem, (ii) mutation of enzymes in TCA cycle (for example, fumarate hydratase) that increases the level of succinyl CoA, a substrate for haem biosynthesis and (iii) metastasis to haem-rich organs such as liver, brain and bone marrow. DISCUSS 191 195 haem chemical Considering microenvironments in and around malignant tumours, the haem concentration in cancer cells is likely to be elevated through multiple mechanisms, such as (i) an increased intake of haem, (ii) mutation of enzymes in TCA cycle (for example, fumarate hydratase) that increases the level of succinyl CoA, a substrate for haem biosynthesis and (iii) metastasis to haem-rich organs such as liver, brain and bone marrow. DISCUSS 249 267 fumarate hydratase protein_type Considering microenvironments in and around malignant tumours, the haem concentration in cancer cells is likely to be elevated through multiple mechanisms, such as (i) an increased intake of haem, (ii) mutation of enzymes in TCA cycle (for example, fumarate hydratase) that increases the level of succinyl CoA, a substrate for haem biosynthesis and (iii) metastasis to haem-rich organs such as liver, brain and bone marrow. DISCUSS 297 309 succinyl CoA chemical Considering microenvironments in and around malignant tumours, the haem concentration in cancer cells is likely to be elevated through multiple mechanisms, such as (i) an increased intake of haem, (ii) mutation of enzymes in TCA cycle (for example, fumarate hydratase) that increases the level of succinyl CoA, a substrate for haem biosynthesis and (iii) metastasis to haem-rich organs such as liver, brain and bone marrow. DISCUSS 327 331 haem chemical Considering microenvironments in and around malignant tumours, the haem concentration in cancer cells is likely to be elevated through multiple mechanisms, such as (i) an increased intake of haem, (ii) mutation of enzymes in TCA cycle (for example, fumarate hydratase) that increases the level of succinyl CoA, a substrate for haem biosynthesis and (iii) metastasis to haem-rich organs such as liver, brain and bone marrow. DISCUSS 369 373 haem chemical Considering microenvironments in and around malignant tumours, the haem concentration in cancer cells is likely to be elevated through multiple mechanisms, such as (i) an increased intake of haem, (ii) mutation of enzymes in TCA cycle (for example, fumarate hydratase) that increases the level of succinyl CoA, a substrate for haem biosynthesis and (iii) metastasis to haem-rich organs such as liver, brain and bone marrow. DISCUSS 220 224 haem chemical Moreover, exposure of cancer cells to stimuli such as hypoxia, radiation and chemotherapy causes cell damages and leads to protein degradation, resulting in increased levels of TCA cycle intermediates and in an enhanced haem biosynthesis. DISCUSS 29 33 haem chemical On the other hand, excessive haem induces HO-1, the enzyme that oxidatively degrades haem and generates CO. DISCUSS 42 46 HO-1 protein On the other hand, excessive haem induces HO-1, the enzyme that oxidatively degrades haem and generates CO. DISCUSS 85 89 haem chemical On the other hand, excessive haem induces HO-1, the enzyme that oxidatively degrades haem and generates CO. DISCUSS 104 106 CO chemical On the other hand, excessive haem induces HO-1, the enzyme that oxidatively degrades haem and generates CO. DISCUSS 6 10 HO-1 protein Thus, HO-1 induction in cancer cells may inhibit the haem-mediated dimerization of PGRMC1 through the production of CO and thereby suppress tumour progression. DISCUSS 53 57 haem chemical Thus, HO-1 induction in cancer cells may inhibit the haem-mediated dimerization of PGRMC1 through the production of CO and thereby suppress tumour progression. DISCUSS 67 79 dimerization oligomeric_state Thus, HO-1 induction in cancer cells may inhibit the haem-mediated dimerization of PGRMC1 through the production of CO and thereby suppress tumour progression. DISCUSS 83 89 PGRMC1 protein Thus, HO-1 induction in cancer cells may inhibit the haem-mediated dimerization of PGRMC1 through the production of CO and thereby suppress tumour progression. DISCUSS 116 118 CO chemical Thus, HO-1 induction in cancer cells may inhibit the haem-mediated dimerization of PGRMC1 through the production of CO and thereby suppress tumour progression. DISCUSS 50 54 HO-1 protein This idea is consistent with the observation that HO-1 induction or CO inhibits tumour growth. DISCUSS 68 70 CO chemical This idea is consistent with the observation that HO-1 induction or CO inhibits tumour growth. DISCUSS 32 38 PGRMC1 protein Besides the regulatory roles of PGRMC1/Sigma-2 receptor in proliferation and chemoresistance in cancer cells (ref.), recent reports show that PGRMC1 is able to bind to amyloid beta oligomer to enhance its neurotoxicity. DISCUSS 39 46 Sigma-2 protein Besides the regulatory roles of PGRMC1/Sigma-2 receptor in proliferation and chemoresistance in cancer cells (ref.), recent reports show that PGRMC1 is able to bind to amyloid beta oligomer to enhance its neurotoxicity. DISCUSS 142 148 PGRMC1 protein Besides the regulatory roles of PGRMC1/Sigma-2 receptor in proliferation and chemoresistance in cancer cells (ref.), recent reports show that PGRMC1 is able to bind to amyloid beta oligomer to enhance its neurotoxicity. DISCUSS 168 180 amyloid beta protein Besides the regulatory roles of PGRMC1/Sigma-2 receptor in proliferation and chemoresistance in cancer cells (ref.), recent reports show that PGRMC1 is able to bind to amyloid beta oligomer to enhance its neurotoxicity. DISCUSS 181 189 oligomer oligomeric_state Besides the regulatory roles of PGRMC1/Sigma-2 receptor in proliferation and chemoresistance in cancer cells (ref.), recent reports show that PGRMC1 is able to bind to amyloid beta oligomer to enhance its neurotoxicity. DISCUSS 13 20 Sigma-2 protein Furthermore, Sigma-2 ligand-binding is decreased in transgenic amyloid beta deposition model APP/PS1 female mice. DISCUSS 48 54 PGRMC1 protein These results suggest a possible involvement of PGRMC1 in Alzheimer's disease. DISCUSS 13 17 haem chemical The roles of haem-dependent dimerization of PGRMC1 in the functional regulation of its target proteins deserve further studies to find evidence that therapeutic interventions to interfere with the function of the dimer may control varied disease conditions. DISCUSS 28 40 dimerization oligomeric_state The roles of haem-dependent dimerization of PGRMC1 in the functional regulation of its target proteins deserve further studies to find evidence that therapeutic interventions to interfere with the function of the dimer may control varied disease conditions. DISCUSS 44 50 PGRMC1 protein The roles of haem-dependent dimerization of PGRMC1 in the functional regulation of its target proteins deserve further studies to find evidence that therapeutic interventions to interfere with the function of the dimer may control varied disease conditions. DISCUSS 213 218 dimer oligomeric_state The roles of haem-dependent dimerization of PGRMC1 in the functional regulation of its target proteins deserve further studies to find evidence that therapeutic interventions to interfere with the function of the dimer may control varied disease conditions. DISCUSS 109 117 oligomer oligomeric_state Alzheimer's therapeutics targeting amyloid beta 1-42 oligomers II: Sigma-2/PGRMC1 receptors mediate Abeta 42 oligomer binding and synaptotoxicity REF 0 23 X-ray crystal structure evidence X-ray crystal structure of PGRMC1. FIG 27 33 PGRMC1 protein X-ray crystal structure of PGRMC1. FIG 21 27 PGRMC1 protein (a) Structure of the PGRMC1 dimer formed through stacked haems. FIG 28 33 dimer oligomeric_state (a) Structure of the PGRMC1 dimer formed through stacked haems. FIG 57 62 haems chemical (a) Structure of the PGRMC1 dimer formed through stacked haems. FIG 4 10 PGRMC1 protein Two PGRMC1 subunits (blue and green ribbons) dimerize via stacking of the haem molecules. FIG 11 19 subunits structure_element Two PGRMC1 subunits (blue and green ribbons) dimerize via stacking of the haem molecules. FIG 45 53 dimerize oligomeric_state Two PGRMC1 subunits (blue and green ribbons) dimerize via stacking of the haem molecules. FIG 58 66 stacking bond_interaction Two PGRMC1 subunits (blue and green ribbons) dimerize via stacking of the haem molecules. FIG 74 78 haem chemical Two PGRMC1 subunits (blue and green ribbons) dimerize via stacking of the haem molecules. FIG 4 8 Haem chemical (b) Haem coordination of PGRMC1 with Tyr113. FIG 9 21 coordination bond_interaction (b) Haem coordination of PGRMC1 with Tyr113. FIG 25 31 PGRMC1 protein (b) Haem coordination of PGRMC1 with Tyr113. FIG 37 43 Tyr113 residue_name_number (b) Haem coordination of PGRMC1 with Tyr113. FIG 14 20 PGRMC1 protein Comparison of PGRMC1 (blue) and cytochrome b5 (yellow, ID: 3NER). (c) PGRMC1 has a longer helix (a.a.147–163), which is shifted away from the haem (arrow). FIG 32 45 cytochrome b5 protein_type Comparison of PGRMC1 (blue) and cytochrome b5 (yellow, ID: 3NER). (c) PGRMC1 has a longer helix (a.a.147–163), which is shifted away from the haem (arrow). FIG 70 76 PGRMC1 protein Comparison of PGRMC1 (blue) and cytochrome b5 (yellow, ID: 3NER). (c) PGRMC1 has a longer helix (a.a.147–163), which is shifted away from the haem (arrow). FIG 90 95 helix structure_element Comparison of PGRMC1 (blue) and cytochrome b5 (yellow, ID: 3NER). (c) PGRMC1 has a longer helix (a.a.147–163), which is shifted away from the haem (arrow). FIG 101 108 147–163 residue_range Comparison of PGRMC1 (blue) and cytochrome b5 (yellow, ID: 3NER). (c) PGRMC1 has a longer helix (a.a.147–163), which is shifted away from the haem (arrow). FIG 142 146 haem chemical Comparison of PGRMC1 (blue) and cytochrome b5 (yellow, ID: 3NER). (c) PGRMC1 has a longer helix (a.a.147–163), which is shifted away from the haem (arrow). FIG 0 6 PGRCM1 protein PGRCM1 is dimerized by binding with haem. FIG 10 19 dimerized protein_state PGRCM1 is dimerized by binding with haem. FIG 36 40 haem chemical PGRCM1 is dimerized by binding with haem. FIG 4 22 Mass spectrometric experimental_method (a) Mass spectrometric analyses of the wild-type (wt) PGRMC1 or the C129S mutant in the presence or absence of haem under non-denaturing condition. FIG 39 48 wild-type protein_state (a) Mass spectrometric analyses of the wild-type (wt) PGRMC1 or the C129S mutant in the presence or absence of haem under non-denaturing condition. FIG 50 52 wt protein_state (a) Mass spectrometric analyses of the wild-type (wt) PGRMC1 or the C129S mutant in the presence or absence of haem under non-denaturing condition. FIG 54 60 PGRMC1 protein (a) Mass spectrometric analyses of the wild-type (wt) PGRMC1 or the C129S mutant in the presence or absence of haem under non-denaturing condition. FIG 68 73 C129S mutant (a) Mass spectrometric analyses of the wild-type (wt) PGRMC1 or the C129S mutant in the presence or absence of haem under non-denaturing condition. FIG 74 80 mutant protein_state (a) Mass spectrometric analyses of the wild-type (wt) PGRMC1 or the C129S mutant in the presence or absence of haem under non-denaturing condition. FIG 88 96 presence protein_state (a) Mass spectrometric analyses of the wild-type (wt) PGRMC1 or the C129S mutant in the presence or absence of haem under non-denaturing condition. FIG 100 110 absence of protein_state (a) Mass spectrometric analyses of the wild-type (wt) PGRMC1 or the C129S mutant in the presence or absence of haem under non-denaturing condition. FIG 111 115 haem chemical (a) Mass spectrometric analyses of the wild-type (wt) PGRMC1 or the C129S mutant in the presence or absence of haem under non-denaturing condition. FIG 41 47 44–195 residue_range Both proteins had identical lengths (a.a.44–195). FIG 4 10 SV-AUC experimental_method (b) SV-AUC analyses of the wt-PGRMC1 and the C129S mutant (a.a.44–195) in the presence or absence of haem. FIG 27 29 wt protein_state (b) SV-AUC analyses of the wt-PGRMC1 and the C129S mutant (a.a.44–195) in the presence or absence of haem. FIG 30 36 PGRMC1 protein (b) SV-AUC analyses of the wt-PGRMC1 and the C129S mutant (a.a.44–195) in the presence or absence of haem. FIG 45 50 C129S mutant (b) SV-AUC analyses of the wt-PGRMC1 and the C129S mutant (a.a.44–195) in the presence or absence of haem. FIG 51 57 mutant protein_state (b) SV-AUC analyses of the wt-PGRMC1 and the C129S mutant (a.a.44–195) in the presence or absence of haem. FIG 63 69 44–195 residue_range (b) SV-AUC analyses of the wt-PGRMC1 and the C129S mutant (a.a.44–195) in the presence or absence of haem. FIG 78 86 presence protein_state (b) SV-AUC analyses of the wt-PGRMC1 and the C129S mutant (a.a.44–195) in the presence or absence of haem. FIG 90 100 absence of protein_state (b) SV-AUC analyses of the wt-PGRMC1 and the C129S mutant (a.a.44–195) in the presence or absence of haem. FIG 101 105 haem chemical (b) SV-AUC analyses of the wt-PGRMC1 and the C129S mutant (a.a.44–195) in the presence or absence of haem. FIG 0 6 SV-AUC experimental_method SV-AUC experiments were performed with 1.5 mg ml−1 of PGRMC1 proteins. FIG 54 60 PGRMC1 protein SV-AUC experiments were performed with 1.5 mg ml−1 of PGRMC1 proteins. FIG 20 45 sedimentation coefficient evidence The major peak with sedimentation coefficient S20,w of 1.9∼2.0 S (monomer) or 3.1 S (dimer) was detected. FIG 46 51 S20,w evidence The major peak with sedimentation coefficient S20,w of 1.9∼2.0 S (monomer) or 3.1 S (dimer) was detected. FIG 66 73 monomer oligomeric_state The major peak with sedimentation coefficient S20,w of 1.9∼2.0 S (monomer) or 3.1 S (dimer) was detected. FIG 85 90 dimer oligomeric_state The major peak with sedimentation coefficient S20,w of 1.9∼2.0 S (monomer) or 3.1 S (dimer) was detected. FIG 4 33 Difference absorption spectra evidence (c) Difference absorption spectra of PGRMC1 (a.a.44–195) titrated with haem (left panel). FIG 37 43 PGRMC1 protein (c) Difference absorption spectra of PGRMC1 (a.a.44–195) titrated with haem (left panel). FIG 49 55 44–195 residue_range (c) Difference absorption spectra of PGRMC1 (a.a.44–195) titrated with haem (left panel). FIG 57 70 titrated with experimental_method (c) Difference absorption spectra of PGRMC1 (a.a.44–195) titrated with haem (left panel). FIG 71 75 haem chemical (c) Difference absorption spectra of PGRMC1 (a.a.44–195) titrated with haem (left panel). FIG 4 19 titration curve evidence The titration curve of haem to PGRMC1 (right panel). FIG 23 27 haem chemical The titration curve of haem to PGRMC1 (right panel). FIG 31 37 PGRMC1 protein The titration curve of haem to PGRMC1 (right panel). FIG 4 25 absorbance difference evidence The absorbance difference at 400 nm is plotted against the haem concentration. FIG 59 63 haem chemical The absorbance difference at 400 nm is plotted against the haem concentration. FIG 0 15 Carbon monoxide chemical Carbon monoxide inhibits haem-dependent PGRMC1 dimerization. FIG 25 29 haem chemical Carbon monoxide inhibits haem-dependent PGRMC1 dimerization. FIG 40 46 PGRMC1 protein Carbon monoxide inhibits haem-dependent PGRMC1 dimerization. FIG 47 59 dimerization oligomeric_state Carbon monoxide inhibits haem-dependent PGRMC1 dimerization. FIG 4 33 UV-visible absorption spectra evidence (a) UV-visible absorption spectra of PGRMC1 (a.a.44–195). FIG 37 43 PGRMC1 protein (a) UV-visible absorption spectra of PGRMC1 (a.a.44–195). FIG 49 55 44–195 residue_range (a) UV-visible absorption spectra of PGRMC1 (a.a.44–195). FIG 35 46 presence of protein_state Measurements were performed in the presence of the oxidized form of haem (ferric), the reduced form of haem (ferrous) and the reduced form of haem plus CO gas (ferrous+CO). FIG 51 59 oxidized protein_state Measurements were performed in the presence of the oxidized form of haem (ferric), the reduced form of haem (ferrous) and the reduced form of haem plus CO gas (ferrous+CO). FIG 68 72 haem chemical Measurements were performed in the presence of the oxidized form of haem (ferric), the reduced form of haem (ferrous) and the reduced form of haem plus CO gas (ferrous+CO). FIG 74 80 ferric protein_state Measurements were performed in the presence of the oxidized form of haem (ferric), the reduced form of haem (ferrous) and the reduced form of haem plus CO gas (ferrous+CO). FIG 87 94 reduced protein_state Measurements were performed in the presence of the oxidized form of haem (ferric), the reduced form of haem (ferrous) and the reduced form of haem plus CO gas (ferrous+CO). FIG 103 107 haem chemical Measurements were performed in the presence of the oxidized form of haem (ferric), the reduced form of haem (ferrous) and the reduced form of haem plus CO gas (ferrous+CO). FIG 109 116 ferrous protein_state Measurements were performed in the presence of the oxidized form of haem (ferric), the reduced form of haem (ferrous) and the reduced form of haem plus CO gas (ferrous+CO). FIG 126 133 reduced protein_state Measurements were performed in the presence of the oxidized form of haem (ferric), the reduced form of haem (ferrous) and the reduced form of haem plus CO gas (ferrous+CO). FIG 142 146 haem chemical Measurements were performed in the presence of the oxidized form of haem (ferric), the reduced form of haem (ferrous) and the reduced form of haem plus CO gas (ferrous+CO). FIG 152 154 CO chemical Measurements were performed in the presence of the oxidized form of haem (ferric), the reduced form of haem (ferrous) and the reduced form of haem plus CO gas (ferrous+CO). FIG 160 167 ferrous protein_state Measurements were performed in the presence of the oxidized form of haem (ferric), the reduced form of haem (ferrous) and the reduced form of haem plus CO gas (ferrous+CO). FIG 168 170 CO chemical Measurements were performed in the presence of the oxidized form of haem (ferric), the reduced form of haem (ferrous) and the reduced form of haem plus CO gas (ferrous+CO). FIG 21 34 haem stacking bond_interaction (b) Close-up view of haem stacking. FIG 4 33 Gel-filtration chromatography experimental_method (c) Gel-filtration chromatography analyses of PGRMC1 (a.a.44–195) wild-type (wt) and the Y113F or C129S mutant in the presence or absence of haem, dithionite and/or CO. (d) Transition model for structural regulation of PGRMC1 in response to haem and CO. FIG 46 52 PGRMC1 protein (c) Gel-filtration chromatography analyses of PGRMC1 (a.a.44–195) wild-type (wt) and the Y113F or C129S mutant in the presence or absence of haem, dithionite and/or CO. (d) Transition model for structural regulation of PGRMC1 in response to haem and CO. FIG 58 64 44–195 residue_range (c) Gel-filtration chromatography analyses of PGRMC1 (a.a.44–195) wild-type (wt) and the Y113F or C129S mutant in the presence or absence of haem, dithionite and/or CO. (d) Transition model for structural regulation of PGRMC1 in response to haem and CO. FIG 66 75 wild-type protein_state (c) Gel-filtration chromatography analyses of PGRMC1 (a.a.44–195) wild-type (wt) and the Y113F or C129S mutant in the presence or absence of haem, dithionite and/or CO. (d) Transition model for structural regulation of PGRMC1 in response to haem and CO. FIG 77 79 wt protein_state (c) Gel-filtration chromatography analyses of PGRMC1 (a.a.44–195) wild-type (wt) and the Y113F or C129S mutant in the presence or absence of haem, dithionite and/or CO. (d) Transition model for structural regulation of PGRMC1 in response to haem and CO. FIG 89 94 Y113F mutant (c) Gel-filtration chromatography analyses of PGRMC1 (a.a.44–195) wild-type (wt) and the Y113F or C129S mutant in the presence or absence of haem, dithionite and/or CO. (d) Transition model for structural regulation of PGRMC1 in response to haem and CO. FIG 98 103 C129S mutant (c) Gel-filtration chromatography analyses of PGRMC1 (a.a.44–195) wild-type (wt) and the Y113F or C129S mutant in the presence or absence of haem, dithionite and/or CO. (d) Transition model for structural regulation of PGRMC1 in response to haem and CO. FIG 104 110 mutant protein_state (c) Gel-filtration chromatography analyses of PGRMC1 (a.a.44–195) wild-type (wt) and the Y113F or C129S mutant in the presence or absence of haem, dithionite and/or CO. (d) Transition model for structural regulation of PGRMC1 in response to haem and CO. FIG 118 126 presence protein_state (c) Gel-filtration chromatography analyses of PGRMC1 (a.a.44–195) wild-type (wt) and the Y113F or C129S mutant in the presence or absence of haem, dithionite and/or CO. (d) Transition model for structural regulation of PGRMC1 in response to haem and CO. FIG 130 140 absence of protein_state (c) Gel-filtration chromatography analyses of PGRMC1 (a.a.44–195) wild-type (wt) and the Y113F or C129S mutant in the presence or absence of haem, dithionite and/or CO. (d) Transition model for structural regulation of PGRMC1 in response to haem and CO. FIG 141 145 haem chemical (c) Gel-filtration chromatography analyses of PGRMC1 (a.a.44–195) wild-type (wt) and the Y113F or C129S mutant in the presence or absence of haem, dithionite and/or CO. (d) Transition model for structural regulation of PGRMC1 in response to haem and CO. FIG 147 157 dithionite chemical (c) Gel-filtration chromatography analyses of PGRMC1 (a.a.44–195) wild-type (wt) and the Y113F or C129S mutant in the presence or absence of haem, dithionite and/or CO. (d) Transition model for structural regulation of PGRMC1 in response to haem and CO. FIG 165 167 CO chemical (c) Gel-filtration chromatography analyses of PGRMC1 (a.a.44–195) wild-type (wt) and the Y113F or C129S mutant in the presence or absence of haem, dithionite and/or CO. (d) Transition model for structural regulation of PGRMC1 in response to haem and CO. FIG 219 225 PGRMC1 protein (c) Gel-filtration chromatography analyses of PGRMC1 (a.a.44–195) wild-type (wt) and the Y113F or C129S mutant in the presence or absence of haem, dithionite and/or CO. (d) Transition model for structural regulation of PGRMC1 in response to haem and CO. FIG 241 245 haem chemical (c) Gel-filtration chromatography analyses of PGRMC1 (a.a.44–195) wild-type (wt) and the Y113F or C129S mutant in the presence or absence of haem, dithionite and/or CO. (d) Transition model for structural regulation of PGRMC1 in response to haem and CO. FIG 250 252 CO chemical (c) Gel-filtration chromatography analyses of PGRMC1 (a.a.44–195) wild-type (wt) and the Y113F or C129S mutant in the presence or absence of haem, dithionite and/or CO. (d) Transition model for structural regulation of PGRMC1 in response to haem and CO. FIG 0 4 Haem chemical Haem-dependent dimerization of PGRMC1 is necessary for tumour proliferation mediated by EGFR signalling. FIG 15 27 dimerization oligomeric_state Haem-dependent dimerization of PGRMC1 is necessary for tumour proliferation mediated by EGFR signalling. FIG 31 37 PGRMC1 protein Haem-dependent dimerization of PGRMC1 is necessary for tumour proliferation mediated by EGFR signalling. FIG 88 92 EGFR protein_type Haem-dependent dimerization of PGRMC1 is necessary for tumour proliferation mediated by EGFR signalling. FIG 9 15 PGRMC1 protein (a) FLAG-PGRMC1 wild-type (wt) and Y113F mutant proteins (a.a.44–195), in either apo- or haem-bound form, were incubated with purified EGFR and co-immunoprecipitated with anti-FLAG antibody-conjugated beads. FIG 16 25 wild-type protein_state (a) FLAG-PGRMC1 wild-type (wt) and Y113F mutant proteins (a.a.44–195), in either apo- or haem-bound form, were incubated with purified EGFR and co-immunoprecipitated with anti-FLAG antibody-conjugated beads. FIG 27 29 wt protein_state (a) FLAG-PGRMC1 wild-type (wt) and Y113F mutant proteins (a.a.44–195), in either apo- or haem-bound form, were incubated with purified EGFR and co-immunoprecipitated with anti-FLAG antibody-conjugated beads. FIG 35 40 Y113F mutant (a) FLAG-PGRMC1 wild-type (wt) and Y113F mutant proteins (a.a.44–195), in either apo- or haem-bound form, were incubated with purified EGFR and co-immunoprecipitated with anti-FLAG antibody-conjugated beads. FIG 41 47 mutant protein_state (a) FLAG-PGRMC1 wild-type (wt) and Y113F mutant proteins (a.a.44–195), in either apo- or haem-bound form, were incubated with purified EGFR and co-immunoprecipitated with anti-FLAG antibody-conjugated beads. FIG 62 68 44–195 residue_range (a) FLAG-PGRMC1 wild-type (wt) and Y113F mutant proteins (a.a.44–195), in either apo- or haem-bound form, were incubated with purified EGFR and co-immunoprecipitated with anti-FLAG antibody-conjugated beads. FIG 81 84 apo protein_state (a) FLAG-PGRMC1 wild-type (wt) and Y113F mutant proteins (a.a.44–195), in either apo- or haem-bound form, were incubated with purified EGFR and co-immunoprecipitated with anti-FLAG antibody-conjugated beads. FIG 89 99 haem-bound protein_state (a) FLAG-PGRMC1 wild-type (wt) and Y113F mutant proteins (a.a.44–195), in either apo- or haem-bound form, were incubated with purified EGFR and co-immunoprecipitated with anti-FLAG antibody-conjugated beads. FIG 111 120 incubated experimental_method (a) FLAG-PGRMC1 wild-type (wt) and Y113F mutant proteins (a.a.44–195), in either apo- or haem-bound form, were incubated with purified EGFR and co-immunoprecipitated with anti-FLAG antibody-conjugated beads. FIG 135 139 EGFR protein_type (a) FLAG-PGRMC1 wild-type (wt) and Y113F mutant proteins (a.a.44–195), in either apo- or haem-bound form, were incubated with purified EGFR and co-immunoprecipitated with anti-FLAG antibody-conjugated beads. FIG 144 165 co-immunoprecipitated experimental_method (a) FLAG-PGRMC1 wild-type (wt) and Y113F mutant proteins (a.a.44–195), in either apo- or haem-bound form, were incubated with purified EGFR and co-immunoprecipitated with anti-FLAG antibody-conjugated beads. FIG 42 58 Western blotting experimental_method Input and bound proteins were detected by Western blotting. FIG 42 58 Western blotting experimental_method Input and bound proteins were detected by Western blotting. FIG 4 26 In vitro binding assay experimental_method (b) In vitro binding assay was performed as in (a) using haem-bound FLAG-PGRMC1 wt (a.a.44–195) and purified EGFR with or without treatment of RuCl3 and CORM3. FIG 57 67 haem-bound protein_state (b) In vitro binding assay was performed as in (a) using haem-bound FLAG-PGRMC1 wt (a.a.44–195) and purified EGFR with or without treatment of RuCl3 and CORM3. FIG 73 79 PGRMC1 protein (b) In vitro binding assay was performed as in (a) using haem-bound FLAG-PGRMC1 wt (a.a.44–195) and purified EGFR with or without treatment of RuCl3 and CORM3. FIG 80 82 wt protein_state (b) In vitro binding assay was performed as in (a) using haem-bound FLAG-PGRMC1 wt (a.a.44–195) and purified EGFR with or without treatment of RuCl3 and CORM3. FIG 88 94 44–195 residue_range (b) In vitro binding assay was performed as in (a) using haem-bound FLAG-PGRMC1 wt (a.a.44–195) and purified EGFR with or without treatment of RuCl3 and CORM3. FIG 109 113 EGFR protein_type (b) In vitro binding assay was performed as in (a) using haem-bound FLAG-PGRMC1 wt (a.a.44–195) and purified EGFR with or without treatment of RuCl3 and CORM3. FIG 143 148 RuCl3 chemical (b) In vitro binding assay was performed as in (a) using haem-bound FLAG-PGRMC1 wt (a.a.44–195) and purified EGFR with or without treatment of RuCl3 and CORM3. FIG 153 158 CORM3 chemical (b) In vitro binding assay was performed as in (a) using haem-bound FLAG-PGRMC1 wt (a.a.44–195) and purified EGFR with or without treatment of RuCl3 and CORM3. FIG 9 15 PGRMC1 protein (c) FLAG-PGRMC1 wt or Y113F (full length) was over-expressed in HCT116 cells and immunoprecipitated with anti-FLAG antibody-conjugated beads. FIG 16 18 wt protein_state (c) FLAG-PGRMC1 wt or Y113F (full length) was over-expressed in HCT116 cells and immunoprecipitated with anti-FLAG antibody-conjugated beads. FIG 22 27 Y113F mutant (c) FLAG-PGRMC1 wt or Y113F (full length) was over-expressed in HCT116 cells and immunoprecipitated with anti-FLAG antibody-conjugated beads. FIG 29 40 full length protein_state (c) FLAG-PGRMC1 wt or Y113F (full length) was over-expressed in HCT116 cells and immunoprecipitated with anti-FLAG antibody-conjugated beads. FIG 46 60 over-expressed experimental_method (c) FLAG-PGRMC1 wt or Y113F (full length) was over-expressed in HCT116 cells and immunoprecipitated with anti-FLAG antibody-conjugated beads. FIG 81 99 immunoprecipitated experimental_method (c) FLAG-PGRMC1 wt or Y113F (full length) was over-expressed in HCT116 cells and immunoprecipitated with anti-FLAG antibody-conjugated beads. FIG 0 21 Co-immunoprecipitated experimental_method Co-immunoprecipitated proteins (FLAG-PGRMC1, endogenous PGRMC1 and EGFR) were detected with Western blotting by using anti-PGRMC1 or anti-EGFR antibody. FIG 37 43 PGRMC1 protein Co-immunoprecipitated proteins (FLAG-PGRMC1, endogenous PGRMC1 and EGFR) were detected with Western blotting by using anti-PGRMC1 or anti-EGFR antibody. FIG 45 55 endogenous protein_state Co-immunoprecipitated proteins (FLAG-PGRMC1, endogenous PGRMC1 and EGFR) were detected with Western blotting by using anti-PGRMC1 or anti-EGFR antibody. FIG 56 62 PGRMC1 protein Co-immunoprecipitated proteins (FLAG-PGRMC1, endogenous PGRMC1 and EGFR) were detected with Western blotting by using anti-PGRMC1 or anti-EGFR antibody. FIG 67 71 EGFR protein_type Co-immunoprecipitated proteins (FLAG-PGRMC1, endogenous PGRMC1 and EGFR) were detected with Western blotting by using anti-PGRMC1 or anti-EGFR antibody. FIG 92 108 Western blotting experimental_method Co-immunoprecipitated proteins (FLAG-PGRMC1, endogenous PGRMC1 and EGFR) were detected with Western blotting by using anti-PGRMC1 or anti-EGFR antibody. FIG 123 129 PGRMC1 protein Co-immunoprecipitated proteins (FLAG-PGRMC1, endogenous PGRMC1 and EGFR) were detected with Western blotting by using anti-PGRMC1 or anti-EGFR antibody. FIG 138 142 EGFR protein_type Co-immunoprecipitated proteins (FLAG-PGRMC1, endogenous PGRMC1 and EGFR) were detected with Western blotting by using anti-PGRMC1 or anti-EGFR antibody. FIG 62 77 succinylacetone chemical (d) HCT116 cells were treated with or without 250 μmol l−1 of succinylacetone (SA) for 48 h. The intracellular haem was extracted and quantified by reverse-phase HPLC. FIG 79 81 SA chemical (d) HCT116 cells were treated with or without 250 μmol l−1 of succinylacetone (SA) for 48 h. The intracellular haem was extracted and quantified by reverse-phase HPLC. FIG 111 115 haem chemical (d) HCT116 cells were treated with or without 250 μmol l−1 of succinylacetone (SA) for 48 h. The intracellular haem was extracted and quantified by reverse-phase HPLC. FIG 148 166 reverse-phase HPLC experimental_method (d) HCT116 cells were treated with or without 250 μmol l−1 of succinylacetone (SA) for 48 h. The intracellular haem was extracted and quantified by reverse-phase HPLC. FIG 54 70 Student's t-test experimental_method of four separate experiments. **P<0.01 using unpaired Student's t-test. (e) Co-immunoprecipitation assay was performed as in (c) with or without SA treatment in HCT116 cells. FIG 76 104 Co-immunoprecipitation assay experimental_method of four separate experiments. **P<0.01 using unpaired Student's t-test. (e) Co-immunoprecipitation assay was performed as in (c) with or without SA treatment in HCT116 cells. FIG 145 147 SA chemical of four separate experiments. **P<0.01 using unpaired Student's t-test. (e) Co-immunoprecipitation assay was performed as in (c) with or without SA treatment in HCT116 cells. FIG 36 41 shRNA chemical (f) HCT116 cells expressing control shRNA or those knocking down PGRMC1 (PGRMC1-KD) were treated with EGF or left untreated, and components of the EGFR signaling pathway were detected by Western blotting. FIG 51 64 knocking down experimental_method (f) HCT116 cells expressing control shRNA or those knocking down PGRMC1 (PGRMC1-KD) were treated with EGF or left untreated, and components of the EGFR signaling pathway were detected by Western blotting. FIG 65 71 PGRMC1 protein (f) HCT116 cells expressing control shRNA or those knocking down PGRMC1 (PGRMC1-KD) were treated with EGF or left untreated, and components of the EGFR signaling pathway were detected by Western blotting. FIG 73 82 PGRMC1-KD mutant (f) HCT116 cells expressing control shRNA or those knocking down PGRMC1 (PGRMC1-KD) were treated with EGF or left untreated, and components of the EGFR signaling pathway were detected by Western blotting. FIG 102 105 EGF protein_type (f) HCT116 cells expressing control shRNA or those knocking down PGRMC1 (PGRMC1-KD) were treated with EGF or left untreated, and components of the EGFR signaling pathway were detected by Western blotting. FIG 147 151 EGFR protein_type (f) HCT116 cells expressing control shRNA or those knocking down PGRMC1 (PGRMC1-KD) were treated with EGF or left untreated, and components of the EGFR signaling pathway were detected by Western blotting. FIG 187 203 Western blotting experimental_method (f) HCT116 cells expressing control shRNA or those knocking down PGRMC1 (PGRMC1-KD) were treated with EGF or left untreated, and components of the EGFR signaling pathway were detected by Western blotting. FIG 48 51 EGF protein_type (g,h) HCT116 cells were treated with or without EGF, SA, RuCl3 and CORM3 as indicated, and components of the EGFR signaling pathway were detected by Western blotting. FIG 53 55 SA chemical (g,h) HCT116 cells were treated with or without EGF, SA, RuCl3 and CORM3 as indicated, and components of the EGFR signaling pathway were detected by Western blotting. FIG 57 62 RuCl3 chemical (g,h) HCT116 cells were treated with or without EGF, SA, RuCl3 and CORM3 as indicated, and components of the EGFR signaling pathway were detected by Western blotting. FIG 67 72 CORM3 chemical (g,h) HCT116 cells were treated with or without EGF, SA, RuCl3 and CORM3 as indicated, and components of the EGFR signaling pathway were detected by Western blotting. FIG 109 113 EGFR protein_type (g,h) HCT116 cells were treated with or without EGF, SA, RuCl3 and CORM3 as indicated, and components of the EGFR signaling pathway were detected by Western blotting. FIG 149 165 Western blotting experimental_method (g,h) HCT116 cells were treated with or without EGF, SA, RuCl3 and CORM3 as indicated, and components of the EGFR signaling pathway were detected by Western blotting. FIG 0 4 Haem chemical Haem-dependent dimerization of PGRMC1 accelerates tumour growth through the EGFR signaling pathway. FIG 15 27 dimerization oligomeric_state Haem-dependent dimerization of PGRMC1 accelerates tumour growth through the EGFR signaling pathway. FIG 31 37 PGRMC1 protein Haem-dependent dimerization of PGRMC1 accelerates tumour growth through the EGFR signaling pathway. FIG 76 80 EGFR protein_type Haem-dependent dimerization of PGRMC1 accelerates tumour growth through the EGFR signaling pathway. FIG 28 34 PGRMC1 protein (a) Nucleotide sequences of PGRMC1 targeted by shRNA and of the shRNA-resistant full length PGRMC1 expression vector. FIG 47 52 shRNA chemical (a) Nucleotide sequences of PGRMC1 targeted by shRNA and of the shRNA-resistant full length PGRMC1 expression vector. FIG 64 79 shRNA-resistant protein_state (a) Nucleotide sequences of PGRMC1 targeted by shRNA and of the shRNA-resistant full length PGRMC1 expression vector. FIG 80 91 full length protein_state (a) Nucleotide sequences of PGRMC1 targeted by shRNA and of the shRNA-resistant full length PGRMC1 expression vector. FIG 92 98 PGRMC1 protein (a) Nucleotide sequences of PGRMC1 targeted by shRNA and of the shRNA-resistant full length PGRMC1 expression vector. FIG 7 23 PGRMC1-knockdown mutant Stable PGRMC1-knockdown (PGRMC1-KD) HCT116 cells were transiently transfected with the shRNA-resistant expression vector of wild-type PGRMC1 (wt) or the Y113F mutant (Y113F). FIG 25 34 PGRMC1-KD mutant Stable PGRMC1-knockdown (PGRMC1-KD) HCT116 cells were transiently transfected with the shRNA-resistant expression vector of wild-type PGRMC1 (wt) or the Y113F mutant (Y113F). FIG 54 77 transiently transfected experimental_method Stable PGRMC1-knockdown (PGRMC1-KD) HCT116 cells were transiently transfected with the shRNA-resistant expression vector of wild-type PGRMC1 (wt) or the Y113F mutant (Y113F). FIG 87 102 shRNA-resistant protein_state Stable PGRMC1-knockdown (PGRMC1-KD) HCT116 cells were transiently transfected with the shRNA-resistant expression vector of wild-type PGRMC1 (wt) or the Y113F mutant (Y113F). FIG 103 120 expression vector experimental_method Stable PGRMC1-knockdown (PGRMC1-KD) HCT116 cells were transiently transfected with the shRNA-resistant expression vector of wild-type PGRMC1 (wt) or the Y113F mutant (Y113F). FIG 124 133 wild-type protein_state Stable PGRMC1-knockdown (PGRMC1-KD) HCT116 cells were transiently transfected with the shRNA-resistant expression vector of wild-type PGRMC1 (wt) or the Y113F mutant (Y113F). FIG 134 140 PGRMC1 protein Stable PGRMC1-knockdown (PGRMC1-KD) HCT116 cells were transiently transfected with the shRNA-resistant expression vector of wild-type PGRMC1 (wt) or the Y113F mutant (Y113F). FIG 142 144 wt protein_state Stable PGRMC1-knockdown (PGRMC1-KD) HCT116 cells were transiently transfected with the shRNA-resistant expression vector of wild-type PGRMC1 (wt) or the Y113F mutant (Y113F). FIG 153 158 Y113F mutant Stable PGRMC1-knockdown (PGRMC1-KD) HCT116 cells were transiently transfected with the shRNA-resistant expression vector of wild-type PGRMC1 (wt) or the Y113F mutant (Y113F). FIG 159 165 mutant protein_state Stable PGRMC1-knockdown (PGRMC1-KD) HCT116 cells were transiently transfected with the shRNA-resistant expression vector of wild-type PGRMC1 (wt) or the Y113F mutant (Y113F). FIG 167 172 Y113F mutant Stable PGRMC1-knockdown (PGRMC1-KD) HCT116 cells were transiently transfected with the shRNA-resistant expression vector of wild-type PGRMC1 (wt) or the Y113F mutant (Y113F). FIG 4 13 Erlotinib chemical (b) Erlotinib was added to HCT116 (control) cells, PGRMC1-KD cells or PGRMC1-KD cells expressing shRNA-resistant PGRMC1 wt or Y113F, and cell viability was examined by MTT assay. FIG 51 60 PGRMC1-KD mutant (b) Erlotinib was added to HCT116 (control) cells, PGRMC1-KD cells or PGRMC1-KD cells expressing shRNA-resistant PGRMC1 wt or Y113F, and cell viability was examined by MTT assay. FIG 70 79 PGRMC1-KD mutant (b) Erlotinib was added to HCT116 (control) cells, PGRMC1-KD cells or PGRMC1-KD cells expressing shRNA-resistant PGRMC1 wt or Y113F, and cell viability was examined by MTT assay. FIG 97 112 shRNA-resistant protein_state (b) Erlotinib was added to HCT116 (control) cells, PGRMC1-KD cells or PGRMC1-KD cells expressing shRNA-resistant PGRMC1 wt or Y113F, and cell viability was examined by MTT assay. FIG 113 119 PGRMC1 protein (b) Erlotinib was added to HCT116 (control) cells, PGRMC1-KD cells or PGRMC1-KD cells expressing shRNA-resistant PGRMC1 wt or Y113F, and cell viability was examined by MTT assay. FIG 120 122 wt protein_state (b) Erlotinib was added to HCT116 (control) cells, PGRMC1-KD cells or PGRMC1-KD cells expressing shRNA-resistant PGRMC1 wt or Y113F, and cell viability was examined by MTT assay. FIG 126 131 Y113F mutant (b) Erlotinib was added to HCT116 (control) cells, PGRMC1-KD cells or PGRMC1-KD cells expressing shRNA-resistant PGRMC1 wt or Y113F, and cell viability was examined by MTT assay. FIG 168 177 MTT assay experimental_method (b) Erlotinib was added to HCT116 (control) cells, PGRMC1-KD cells or PGRMC1-KD cells expressing shRNA-resistant PGRMC1 wt or Y113F, and cell viability was examined by MTT assay. FIG 30 32 *P evidence of four separate experiments. *P<0.01 using ANOVA with Fischer's LSD test. FIG 44 49 ANOVA experimental_method of four separate experiments. *P<0.01 using ANOVA with Fischer's LSD test. FIG 55 73 Fischer's LSD test experimental_method of four separate experiments. *P<0.01 using ANOVA with Fischer's LSD test. FIG 30 32 *P evidence of four separate experiments. *P<0.01 using ANOVA with Fischer's LSD test. FIG 44 49 ANOVA experimental_method of four separate experiments. *P<0.01 using ANOVA with Fischer's LSD test. FIG 55 73 Fischer's LSD test experimental_method of four separate experiments. *P<0.01 using ANOVA with Fischer's LSD test. FIG 38 47 PGRMC1-KD mutant (c) Spheroid formation in control and PGRMC1-KD HCT116 cells. FIG 54 56 *P evidence The graph represents mean±s.e. of each spheroid size. *P<0.01 using ANOVA with Fischer's LSD test. FIG 68 73 ANOVA experimental_method The graph represents mean±s.e. of each spheroid size. *P<0.01 using ANOVA with Fischer's LSD test. FIG 79 97 Fischer's LSD test experimental_method The graph represents mean±s.e. of each spheroid size. *P<0.01 using ANOVA with Fischer's LSD test. FIG 74 96 intrasplenic injection experimental_method Scale bar: 0.1 mm. (d) Tumour-bearing livers of NOG mice at 10 days after intrasplenic injection of HCT116 (control) or PGRMC1-KD cells. FIG 120 129 PGRMC1-KD mutant Scale bar: 0.1 mm. (d) Tumour-bearing livers of NOG mice at 10 days after intrasplenic injection of HCT116 (control) or PGRMC1-KD cells. FIG 28 30 *P evidence of 10 separate experiments. *P<0.05 using unpaired Student's t-test. FIG 51 67 Student's t-test experimental_method of 10 separate experiments. *P<0.05 using unpaired Student's t-test. FIG 0 4 Haem chemical Haem-dependent PGRMC1 dimerization enhances tumour chemoresistance through interaction with cytochromes P450. FIG 15 21 PGRMC1 protein Haem-dependent PGRMC1 dimerization enhances tumour chemoresistance through interaction with cytochromes P450. FIG 22 34 dimerization oligomeric_state Haem-dependent PGRMC1 dimerization enhances tumour chemoresistance through interaction with cytochromes P450. FIG 92 108 cytochromes P450 protein_type Haem-dependent PGRMC1 dimerization enhances tumour chemoresistance through interaction with cytochromes P450. FIG 11 17 PGRMC1 protein (a,b) FLAG-PGRMC1 wild-type (wt) and Y113F mutant proteins (a.a.44–195), in either apo or haem-bound form, were incubated with CYP1A2 (a) or CYP3A4 (b) and immunoprecipitated with anti-FLAG antibody-conjugated beads. FIG 18 27 wild-type protein_state (a,b) FLAG-PGRMC1 wild-type (wt) and Y113F mutant proteins (a.a.44–195), in either apo or haem-bound form, were incubated with CYP1A2 (a) or CYP3A4 (b) and immunoprecipitated with anti-FLAG antibody-conjugated beads. FIG 29 31 wt protein_state (a,b) FLAG-PGRMC1 wild-type (wt) and Y113F mutant proteins (a.a.44–195), in either apo or haem-bound form, were incubated with CYP1A2 (a) or CYP3A4 (b) and immunoprecipitated with anti-FLAG antibody-conjugated beads. FIG 37 42 Y113F mutant (a,b) FLAG-PGRMC1 wild-type (wt) and Y113F mutant proteins (a.a.44–195), in either apo or haem-bound form, were incubated with CYP1A2 (a) or CYP3A4 (b) and immunoprecipitated with anti-FLAG antibody-conjugated beads. FIG 43 49 mutant protein_state (a,b) FLAG-PGRMC1 wild-type (wt) and Y113F mutant proteins (a.a.44–195), in either apo or haem-bound form, were incubated with CYP1A2 (a) or CYP3A4 (b) and immunoprecipitated with anti-FLAG antibody-conjugated beads. FIG 64 70 44–195 residue_range (a,b) FLAG-PGRMC1 wild-type (wt) and Y113F mutant proteins (a.a.44–195), in either apo or haem-bound form, were incubated with CYP1A2 (a) or CYP3A4 (b) and immunoprecipitated with anti-FLAG antibody-conjugated beads. FIG 83 86 apo protein_state (a,b) FLAG-PGRMC1 wild-type (wt) and Y113F mutant proteins (a.a.44–195), in either apo or haem-bound form, were incubated with CYP1A2 (a) or CYP3A4 (b) and immunoprecipitated with anti-FLAG antibody-conjugated beads. FIG 90 100 haem-bound protein_state (a,b) FLAG-PGRMC1 wild-type (wt) and Y113F mutant proteins (a.a.44–195), in either apo or haem-bound form, were incubated with CYP1A2 (a) or CYP3A4 (b) and immunoprecipitated with anti-FLAG antibody-conjugated beads. FIG 112 121 incubated experimental_method (a,b) FLAG-PGRMC1 wild-type (wt) and Y113F mutant proteins (a.a.44–195), in either apo or haem-bound form, were incubated with CYP1A2 (a) or CYP3A4 (b) and immunoprecipitated with anti-FLAG antibody-conjugated beads. FIG 127 133 CYP1A2 protein (a,b) FLAG-PGRMC1 wild-type (wt) and Y113F mutant proteins (a.a.44–195), in either apo or haem-bound form, were incubated with CYP1A2 (a) or CYP3A4 (b) and immunoprecipitated with anti-FLAG antibody-conjugated beads. FIG 141 147 CYP3A4 protein (a,b) FLAG-PGRMC1 wild-type (wt) and Y113F mutant proteins (a.a.44–195), in either apo or haem-bound form, were incubated with CYP1A2 (a) or CYP3A4 (b) and immunoprecipitated with anti-FLAG antibody-conjugated beads. FIG 156 174 immunoprecipitated experimental_method (a,b) FLAG-PGRMC1 wild-type (wt) and Y113F mutant proteins (a.a.44–195), in either apo or haem-bound form, were incubated with CYP1A2 (a) or CYP3A4 (b) and immunoprecipitated with anti-FLAG antibody-conjugated beads. FIG 4 17 Binding assay experimental_method (c) Binding assay was performed as in (a) using haem-bound FLAG-PGRMC1 wt and CYP1A2 with or without RuCl3 and CORM3. FIG 48 58 haem-bound protein_state (c) Binding assay was performed as in (a) using haem-bound FLAG-PGRMC1 wt and CYP1A2 with or without RuCl3 and CORM3. FIG 64 70 PGRMC1 protein (c) Binding assay was performed as in (a) using haem-bound FLAG-PGRMC1 wt and CYP1A2 with or without RuCl3 and CORM3. FIG 71 73 wt protein_state (c) Binding assay was performed as in (a) using haem-bound FLAG-PGRMC1 wt and CYP1A2 with or without RuCl3 and CORM3. FIG 78 84 CYP1A2 protein (c) Binding assay was performed as in (a) using haem-bound FLAG-PGRMC1 wt and CYP1A2 with or without RuCl3 and CORM3. FIG 101 106 RuCl3 chemical (c) Binding assay was performed as in (a) using haem-bound FLAG-PGRMC1 wt and CYP1A2 with or without RuCl3 and CORM3. FIG 111 116 CORM3 chemical (c) Binding assay was performed as in (a) using haem-bound FLAG-PGRMC1 wt and CYP1A2 with or without RuCl3 and CORM3. FIG 30 41 doxorubicin chemical (d) Schematic illustration of doxorubicin metabolism is shown on the left. FIG 0 11 Doxorubicin chemical Doxorubicin was incubated with HCT116 cells expressing control shRNA or shPGRMC1 (PGRMC1-KD), and the doxorubicinol/doxorubicin ratios in cell pellets were determined using LC-MS. FIG 16 25 incubated experimental_method Doxorubicin was incubated with HCT116 cells expressing control shRNA or shPGRMC1 (PGRMC1-KD), and the doxorubicinol/doxorubicin ratios in cell pellets were determined using LC-MS. FIG 63 68 shRNA chemical Doxorubicin was incubated with HCT116 cells expressing control shRNA or shPGRMC1 (PGRMC1-KD), and the doxorubicinol/doxorubicin ratios in cell pellets were determined using LC-MS. FIG 72 80 shPGRMC1 chemical Doxorubicin was incubated with HCT116 cells expressing control shRNA or shPGRMC1 (PGRMC1-KD), and the doxorubicinol/doxorubicin ratios in cell pellets were determined using LC-MS. FIG 82 91 PGRMC1-KD mutant Doxorubicin was incubated with HCT116 cells expressing control shRNA or shPGRMC1 (PGRMC1-KD), and the doxorubicinol/doxorubicin ratios in cell pellets were determined using LC-MS. FIG 102 115 doxorubicinol chemical Doxorubicin was incubated with HCT116 cells expressing control shRNA or shPGRMC1 (PGRMC1-KD), and the doxorubicinol/doxorubicin ratios in cell pellets were determined using LC-MS. FIG 116 127 doxorubicin chemical Doxorubicin was incubated with HCT116 cells expressing control shRNA or shPGRMC1 (PGRMC1-KD), and the doxorubicinol/doxorubicin ratios in cell pellets were determined using LC-MS. FIG 173 178 LC-MS experimental_method Doxorubicin was incubated with HCT116 cells expressing control shRNA or shPGRMC1 (PGRMC1-KD), and the doxorubicinol/doxorubicin ratios in cell pellets were determined using LC-MS. FIG 31 33 *P evidence of four separate experiments. **P<0.01 versus control using unpaired Student's t-test. (e) Indicated amounts of doxorubicin were added to HCT116 (control) cells, PGRMC1-KD cells, or PGRMC1-KD cells expressing shRNA-resistant full-length PGRMC1 wt or Y113F, and cell viability was examined by MTT assay. FIG 69 85 Student's t-test experimental_method of four separate experiments. **P<0.01 versus control using unpaired Student's t-test. (e) Indicated amounts of doxorubicin were added to HCT116 (control) cells, PGRMC1-KD cells, or PGRMC1-KD cells expressing shRNA-resistant full-length PGRMC1 wt or Y113F, and cell viability was examined by MTT assay. FIG 112 123 doxorubicin chemical of four separate experiments. **P<0.01 versus control using unpaired Student's t-test. (e) Indicated amounts of doxorubicin were added to HCT116 (control) cells, PGRMC1-KD cells, or PGRMC1-KD cells expressing shRNA-resistant full-length PGRMC1 wt or Y113F, and cell viability was examined by MTT assay. FIG 162 171 PGRMC1-KD mutant of four separate experiments. **P<0.01 versus control using unpaired Student's t-test. (e) Indicated amounts of doxorubicin were added to HCT116 (control) cells, PGRMC1-KD cells, or PGRMC1-KD cells expressing shRNA-resistant full-length PGRMC1 wt or Y113F, and cell viability was examined by MTT assay. FIG 182 191 PGRMC1-KD mutant of four separate experiments. **P<0.01 versus control using unpaired Student's t-test. (e) Indicated amounts of doxorubicin were added to HCT116 (control) cells, PGRMC1-KD cells, or PGRMC1-KD cells expressing shRNA-resistant full-length PGRMC1 wt or Y113F, and cell viability was examined by MTT assay. FIG 209 224 shRNA-resistant protein_state of four separate experiments. **P<0.01 versus control using unpaired Student's t-test. (e) Indicated amounts of doxorubicin were added to HCT116 (control) cells, PGRMC1-KD cells, or PGRMC1-KD cells expressing shRNA-resistant full-length PGRMC1 wt or Y113F, and cell viability was examined by MTT assay. FIG 225 236 full-length protein_state of four separate experiments. **P<0.01 versus control using unpaired Student's t-test. (e) Indicated amounts of doxorubicin were added to HCT116 (control) cells, PGRMC1-KD cells, or PGRMC1-KD cells expressing shRNA-resistant full-length PGRMC1 wt or Y113F, and cell viability was examined by MTT assay. FIG 237 243 PGRMC1 protein of four separate experiments. **P<0.01 versus control using unpaired Student's t-test. (e) Indicated amounts of doxorubicin were added to HCT116 (control) cells, PGRMC1-KD cells, or PGRMC1-KD cells expressing shRNA-resistant full-length PGRMC1 wt or Y113F, and cell viability was examined by MTT assay. FIG 244 246 wt protein_state of four separate experiments. **P<0.01 versus control using unpaired Student's t-test. (e) Indicated amounts of doxorubicin were added to HCT116 (control) cells, PGRMC1-KD cells, or PGRMC1-KD cells expressing shRNA-resistant full-length PGRMC1 wt or Y113F, and cell viability was examined by MTT assay. FIG 250 255 Y113F mutant of four separate experiments. **P<0.01 versus control using unpaired Student's t-test. (e) Indicated amounts of doxorubicin were added to HCT116 (control) cells, PGRMC1-KD cells, or PGRMC1-KD cells expressing shRNA-resistant full-length PGRMC1 wt or Y113F, and cell viability was examined by MTT assay. FIG 292 301 MTT assay experimental_method of four separate experiments. **P<0.01 versus control using unpaired Student's t-test. (e) Indicated amounts of doxorubicin were added to HCT116 (control) cells, PGRMC1-KD cells, or PGRMC1-KD cells expressing shRNA-resistant full-length PGRMC1 wt or Y113F, and cell viability was examined by MTT assay. FIG 40 46 PGRMC1 protein Schematic diagram for the regulation of PGRMC1 functions. FIG 0 3 Apo protein_state Apo-PGRMC1 exists as an inactive monomer. FIG 4 10 PGRMC1 protein Apo-PGRMC1 exists as an inactive monomer. FIG 24 32 inactive protein_state Apo-PGRMC1 exists as an inactive monomer. FIG 33 40 monomer oligomeric_state Apo-PGRMC1 exists as an inactive monomer. FIG 3 13 binding to protein_state On binding to haem, PGRMC1 forms a dimer through stacking interactions between the haem moieties, which enables PGRMC1 to interact with EGFR and cytochromes P450, leading to an enhanced proliferation and chemoresistance of cancer cells. FIG 14 18 haem chemical On binding to haem, PGRMC1 forms a dimer through stacking interactions between the haem moieties, which enables PGRMC1 to interact with EGFR and cytochromes P450, leading to an enhanced proliferation and chemoresistance of cancer cells. FIG 20 26 PGRMC1 protein On binding to haem, PGRMC1 forms a dimer through stacking interactions between the haem moieties, which enables PGRMC1 to interact with EGFR and cytochromes P450, leading to an enhanced proliferation and chemoresistance of cancer cells. FIG 35 40 dimer oligomeric_state On binding to haem, PGRMC1 forms a dimer through stacking interactions between the haem moieties, which enables PGRMC1 to interact with EGFR and cytochromes P450, leading to an enhanced proliferation and chemoresistance of cancer cells. FIG 49 70 stacking interactions bond_interaction On binding to haem, PGRMC1 forms a dimer through stacking interactions between the haem moieties, which enables PGRMC1 to interact with EGFR and cytochromes P450, leading to an enhanced proliferation and chemoresistance of cancer cells. FIG 83 87 haem chemical On binding to haem, PGRMC1 forms a dimer through stacking interactions between the haem moieties, which enables PGRMC1 to interact with EGFR and cytochromes P450, leading to an enhanced proliferation and chemoresistance of cancer cells. FIG 112 118 PGRMC1 protein On binding to haem, PGRMC1 forms a dimer through stacking interactions between the haem moieties, which enables PGRMC1 to interact with EGFR and cytochromes P450, leading to an enhanced proliferation and chemoresistance of cancer cells. FIG 136 140 EGFR protein_type On binding to haem, PGRMC1 forms a dimer through stacking interactions between the haem moieties, which enables PGRMC1 to interact with EGFR and cytochromes P450, leading to an enhanced proliferation and chemoresistance of cancer cells. FIG 145 161 cytochromes P450 protein_type On binding to haem, PGRMC1 forms a dimer through stacking interactions between the haem moieties, which enables PGRMC1 to interact with EGFR and cytochromes P450, leading to an enhanced proliferation and chemoresistance of cancer cells. FIG 0 2 CO chemical CO interferes with the stacking interactions of the haems and thereby inhibits PGRMC1 functions. FIG 23 44 stacking interactions bond_interaction CO interferes with the stacking interactions of the haems and thereby inhibits PGRMC1 functions. FIG 52 57 haems chemical CO interferes with the stacking interactions of the haems and thereby inhibits PGRMC1 functions. FIG 79 85 PGRMC1 protein CO interferes with the stacking interactions of the haems and thereby inhibits PGRMC1 functions. FIG 39 51 dimerization oligomeric_state PGRMC1 proteins exhibit haem-dependent dimerization in solution. TABLE 360 365 C129S mutant "  Apo form Haem-bound form     Mass (Da)   Mass (Da) aPGRMC1 wt (a.a.44–195)  ESI-MS — 17,844.14 — 36,920.19  Theoretical   17,843.65   36,918.06   Hydrodynamic radius 10−9 (m) MW (kDa) Hydrodynamic radius 10−9 (m) MW (kDa)  DOSY 2.04–2.15 20 2.94–3.02 42   S20,w (S) MW (kDa) S20,w (S) MW (kDa)  SV-AUC 1.9 17.6 3.1 35.5           bPGRMC1 C129S (a.a.44–195)  ESI-MS — 17,827.91 — 36,887.07  Theoretical   17,827.59   36,885.6   S20,w (S) MW (kDa) S20,w (S) MW (kDa)  SV-AUC 2.0 18.1 3.1 35.8 " TABLE 66 71 C129S mutant Differences in molecular weights of the wild-type (wt; a) and the C129S mutant (b) PGRMC1 proteins in the absence (apo form) or the presence of haem (haem-bound form). TABLE 32 37 C129S mutant The protein sizes of the wt and C129S PGRMC1 cytosolic domains (a.a.44–195) in the presence or absence of haem were estimated by ESI-MS, DOSY and SV-AUC. TABLE