EMBO/soda-nel huggingface dataset:
ZBTB2 links p53-deficiency to HIF-1-mediated hypoxia signaling to promote cancer aggressiveness (2022)
Figure 4

Figure 4. Homodimerization of ZBTB2 via its N terminus increases the transactivation activity of HIF-1α.

A, The indicated cells transiently transfected with pEF6/ZBTB2 (ZBTB2) or pEF6/myc-His B (EV) were cultured under the indicated oxygen conditions for 24 hours and subjected to Western blotting using the indicated antibodies.

B-F, The indicated cells transiently transfected with both pG5H1bLuc and either pcDNA6/Gal4 DBD-HIF-1α TAD P564A (B-D,F) or pcDNA6/Gal4 DBD-HIF-1α TAD P564A and N803A (E) were additionally co-transfected with either pEF6/myc-His B (EV), pEF6/ZBTB2 (ZBTB2), pEF6/ZBTB2 del[1-23] (del[1-23]), pEF6/ZBTB2 del[BTB/POZ] (del[BTB]), pEF6/ZBTB2 del[ZF1] (del[ZF1]), pEF6/ZBTB2 del[ZF2] (del[ZF2]), pEF6/ZBTB2 del[ZF3] (del[ZF3]), or pEF6/ZBTB2 del[ZF4]- (del[ZF4]), as indicated (B,D,E,F) or with the indicated siRNA (C,D). The cells were then cultured under the indicated oxygen conditions for 24 hours and subjected to the luciferase assay.

G, Protein sequence alignments of the N-terminus regions of hMN and ZBTB2.

H, After transient transfection with the expression vectors for ZBTB2-V5, ZBTB2-myc, or their empty vector (-), ZBTB2-myc protein was immunoprecipitated using the anti-myc antibody and co-precipitated ZBTB2-V5 was detected using the anti-V5 antibody (upper). One-tenth of the whole cell lysate (WCL) was subjected to immunoblotting with the indicated antibodies (lower).

I,J, The indicated cells transiently transfected with or without either pcDNA4/ZBTB2-LgBiT or pcDNA4/LgBiT and either pcDNA4/ZBTB2-SmBiT or pcDNA4/SmBiT, as indicated, were cultured under < 0.1% oxygen (I) or the indicated oxygen conditions (J) and subjected to the split luciferase complementation assay.

K, HeLa cells overexpressing wildtype or the indicated mutant of ZBTB2 (ZF2 or ZF3-deletion) were cultured under < 0.1% oxygen conditions, and subjected to immunoprecipitation with anti-myc antibody. Coprecipitated DNA was subjected to the qRT-PCR experiment using primers against HRE regions of the STC1 promoter.

L, The same experiment as I was conducted using the indicated combination of pcDNA4/ZBTB2-LgBiT (WT), pcDNA4/ZBTB2ΔZF2-LgBiT (ΔZF2), or pcDNA4/ZBTB2ΔZF3-LgBiT (ΔZF3), and pcDNA4/ZBTB2-SmBiT (WT), pcDNA4/ZBTB2ΔZF2-SmBiT (ΔZF2), or pcDNA4/ZBTB2ΔZF3-SmBiT (ΔZF3).

Data information: Mean ± s.d. The number of technical replicates in all of the experimental groups was 3 (B-F,I-L), and reproducibility of the results was confirmed at least 3 times by biologically independent experiments (A-L). N.S.: not significant, *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001, Student's t-test (B-F,I-L).
ZBTB2 links p53-deficiency to HIF-1-mediated hypoxia signaling to promote cancer aggressiveness (2022)
Figure 5

Figure 5. Targeting ZBTB2 homodimer formation as a rational strategy to inhibit the growth of functional p53-deficient cancers.

A, A homology model of the N terminus of ZBTB2 based on the hMN crystal structure. L3-23L (cyan), A86-L89 (pink), and P106-L113 (yellow). (Left) Top view. (Right) Side view.

B, HCT116 p53-/- cells co-transfected with pG5H1bLuc, pcDNA6/Gal4 DBD-HIF-1α TAD P564A, and either pEF6/ZBTB2 (ZBTB2), pEF6/ZBTB2 del[8-11] (ZBTB2 del[8-11]), pEF6/ZBTB2 del[51-54] (ZBTB2 del[51-54]), or pEF6/myc-His B (EV), as indicated, were cultured under < 0.1% oxygen conditions for 24 hours and subjected to the luciferase assay.

C, After transient transfection with or without the expression vectors for ZBTB2-V5, ZBTB2 4A-V5, ZBTB2-myc, ZBTB2 4A-myc, or their empty vector, as indicated, the myc-fused proteins were immunoprecipitated using an anti-myc antibody and co-precipitated ZBTB2-V5 or ZBTB2 4A-V5 was detected (upper). One-tenth of the whole cell lysate (WCL) was subjected to immunoblotting with the indicated antibodies (lower).

D, HCT116 p53-/- (left) cells transiently transfected with or without either pcDNA4/ZBTB2-LgBiT (ZBTB2), pcDNA4/ZBTB2 4A-LgBiT 4A (4A), or pcDNA4/LgBiT (-) and either pcDNA4/ZBTB2-SmBiT (ZBTB2), pcDNA4/ZBTB2 4A-SmBiT (4A), or pcDNA4/SmBiT (-), as indicated, were cultured under < 0.1% oxygen and subjected to the split luciferase complementation assay.

E, Root mean square deviation (RMSD) of the backbone Cα atoms with respect to the MD-initial structure for the native (blue) and 4A mutant (red) ZBTB2 monomer proteins.

F, RMSF of the backbone Cα atoms for the native (blue) and 4A mutant (red) ZBTB2 monomer proteins.

G, The same kind of luciferase assay to quantify the transactivation activity as B was carried out using either pEF6/ZBTB2 (ZBTB2), pEF6/ZBTB2 4A (4A), or pEF6/myc-His B (EV).

H, Growth of the indicated tumor xenografts was analyzed.

Data information: Mean ± s.d. The number of technical replicates was 3 (B,D,G) and 7 (H), and reproducibility of the results was confirmed at least 3 times by biologically independent experiments (B-D,G,H). N.S.: not significant, *P < 0.05, **P < 0.01, ****P < 0.0001, Student's t-test (B,D,G,H).
Humanized COVID-19 decoy antibody effectively blocks viral entry and prevents SARS-CoV-2 infection (2020)
Figure 1

Figure 1. Production of the decoy antibody (chimeric ACE2-Fc).

(A) Schematic diagram of SARS-CoV-2 Spike protein and the Spike constructs, Spike 1-1273 (full length), 1-674 (S1), and 319-591 (RBD-SD1) used in this study. The arrows indicate the cleavage sites of furin and TMPRSS2.

(B) Western blot analysis of SARS-CoV-2 Spike 1-1273, 1-674, and 319-591 expression in HEK293T cells. The black arrows indicate the location of the induced target proteins.

(C) Detection of decoy antibody ACE2-Fc and Spike S1-Fc chimeric homodimer formation in nonreducing Coomassie Brilliant Blue staining.

(D) Recognition of the ACE2-Fc and Spike S1-Fc by anti-human IgG Fc antibody in nonreducing sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). (E, F) Deglycosylation of ACE2-Fc and Spike 1-674-Fc by PNGase F. PNGase F digested ACE2-Fc (500 ng) and Spike 1-674-Fc (500 ng) were subjected to Coomassie Brilliant Blue staining (E) and Western blot analysis by anti-human IgG Fc antibody (F).

Data information: NTD: N-terminal domain; RBD: receptor-binding domain; SD: connector domain; TM: transmembrane domain; CT: cytoplasmic tail; FP: fusion peptide. IB, immunoblotted with the indicated antibodies. GAPDH served as a loading control. Experiments were performed at least three times with similar results.
Humanized COVID-19 decoy antibody effectively blocks viral entry and prevents SARS-CoV-2 infection (2020)
Figure 2

Figure 2. Functional characterization of the decoy antibody.

(A) Competitive ELISA. ACE2-Fc can compete with ACE2-Fc-Biotin for Spike 1-674 binding in a dose-dependent manner. The competition effects of ACE2-Fc on ACE2-Spike protein binding was normalized to PBS control. Error bars represent the standard deviation (SD), n=2. Statistical analysis was performed by unpaired two tail t-test. **P < 0.01, ***P < 0.001.

(B) Recognition of full-length Spike on H1975 (left panel as negative control) or H1975-Spike (right panel) cells by ACE2-Fc using flow cytometry analysis. Isotype control: 40 μg/mL mouse IgG-FITC.

(C) Confocal microscopy of H1975-Spike-overexpressing cells. Spikes on H1975 cells were stained with anti-Spike antibody and Alexa Fluor® 594-conjugated secondary antibody on ice for 1 hr. After that, ACE2-Fc-FITC was incubated for another 1 hr. Scale bars equal to 20 µm. DAPI was used as a nuclear counterstain.

(D) Preservation of ACE2-Fc peptidase activity. The peptidase activity of ACE2-Fc was measured by cleavage of the fluorescent peptide substrates.

(E) Inhibition of angiotensin II (Ang II)-induced TNF-α production by ACE2-Fc. Ang II was preincubated with indicated amounts of ACE2-Fc or IgG for 30 minutes. After that, the mixtures were added to RAW264.7 cells for 12 hr. The concentration of TNF-α in the culture medium was determined by ELISA. Error bars represent the standard deviation (SD), n=3. Statistical analysis was performed by unpaired two tail t-test. *P < 0.05. The dotted line represents the mean value of TNF-α in control group.

(F) Inhibition of Ang II-induced ADAM17 (a disintegrin and metalloprotease 17) phosphorylation by ACE2-Fc. The protein extracts from (E) were immunoblotted with the indicated antibodies (left panel). β-actin served as the loading control. The signal intensity was normalized to cells only (right panel). Data are representative of three independent experiments, and the values are expressed as the mean ± SD (right panel). Error bars represent the standard deviation (SD), n=2. Statistical analysis was performed by unpaired two tail t-test. *P < 0.05. IgG represents the human normal IgG control.
Humanized COVID-19 decoy antibody effectively blocks viral entry and prevents SARS-CoV-2 infection (2020)
Figure 3

Figure 3. Inhibition of Spike-induced cell-cell fusion and syncytia formation by ACE2-Fc.

(A) The schematic diagram for cell-cell fusion and syncytia formation.

(B) HEK293 and H1975 cells were transduced with full-length ACE2 by lentivirus. Protein extracts were immunoblotted with the indicated antibodies. O/E represents overexpression.

(C) GFP and full-length Spike co-transfected HEK293T cells were used as effector cells (293-S). HEK293/ACE2 (HEK293T-overexpressing ACE2) (left panel) or H1975/ACE2 (H1975-overexpressing ACE2) (right panel) cells were used as target cells. The 293-S cells were preincubated with normal human IgG or ACE2-Fc at 37°C for 1 hr. After that, the mixtures were added to target cells for 4 hr (cell-cell fusion) or 24 hr (syncytia formation). The fluorescent areas were measured by inverted fluorescence microscopy and Metamorph software (Metamorphosis). Scale bars equal to 50 µm. The white arrows indicate the cell-cell fusion or syncytia formation.

(D) The inhibition of cell-cell fusion and syncytia formation by ACE2-Fc in HEK293/ACE2 and H1975/ACE2 was determined with the formula described in the Methods section. Error bars represent the standard deviation (SD), n=6. Statistical analysis was performed by unpaired two tail t-test. ** P < 0.01, *** P < 0.001.
Humanized COVID-19 decoy antibody effectively blocks viral entry and prevents SARS-CoV-2 infection (2020)
Figure 4

Figure 4. Blockage of Spike-expressing pseudovirus entry into ACE2-expressing cells by ACE2-Fc.

(A) ACE2-Fc blocked the entry of Spike-expressing pseudotyped lentivirus into HEK293T-ACE2 and H1975-ACE2 cells. The relative luciferase activities, normalized to the only virus group, represent the efficiency of virus entry. MOI: Multiplicity of infection.

(B-D) Airway organoid model system. (B) Confocal microscopy images of the airway organoids. The green fluorescence represents the specific staining of indicated monoclonal antibodies and Alexa Fluor 488-conjugated secondary antibodies. DAPI was used as a nuclear counterstain. Hematoxylin and eosin (H&E) stain: hematoxylin stained the nuclei in blue color; eosin stained the cytoplasm in pink color. Scale bars equal to 20 µm. (C) Lung cancer A549 cells, human normal bronchial epithelial cells (HBEpc), and HBEpc-differentiated cells (airway organoids) were harvested for immunoblotting with the indicated antibodies. (D) Blockage of pseudovirus entry into airway organoids by ACE2-Fc. Mixtures of pseudotyped lentivirus with or without ACE2-Fc were cocultured with airway organoids for 72 hr. The virus entry was determined by quantifying the luciferase activity in the cell lysates.

Data information: Error bars represent the standard deviation (SD), n=3. Statistical analysis was performed by unpaired two tail t-test. * P < 0,05, ** P < 0.01, *** P < 0.001. Experiments were performed at least three times with similar results.
Humanized COVID-19 decoy antibody effectively blocks viral entry and prevents SARS-CoV-2 infection (2020)
Figure 5

Figure 5. Blockage of SARS-CoV-2 entry into host cells by ACE2-Fc.

(A) Inhibition of SARS-CoV-2 infection by ACE2-Fc in the plaque assay. Mixtures of ACE2-Fc and SARS-CoV-2 were incubated for one hour before adding to Vero E6 cells for another 1 hr at 37°C. The ACE2-Fc and SARS-CoV-2 premixtures were removed, and the cells were washed once with PBS and overlaid with methylcellulose with 2% FBS for 5-7 days before being stained with crystal violet. Those results showed increase of plaque formation was regarded as no inhibition of plaque formation. TPCK-treated trypsin: N-tosyl-L-phenylalanine chloromethyl ketone-treated trypsin.

(B-C) Yield reduction assay was performed to determine the inhibitory effects of ACE2-Fc on virus titers and protein expression. The culture medium and cell extracts were harvested 24 hours post-infection for real-time PCR (B) and western blot (C). The NP/PCNA represents the relative NP expression as compared to that of PCNA, which served as a loading control. The NP/PCNA numbers below the panel are the ratios of NP/PCNA normalized to that of the human IgG control group. PCNA: Proliferating cell nuclear antigen.

(D) Schematic illustration of the ACE2-Fc pretreatment and full-time experiment procedure, delineating the stages where the ACE2-Fc was present during the experiment.

(E) The cell lysates from the pretreatment and full-time experiments were harvested and immunoblotted with the indicated antibodies.

(F) The SARS-CoV-2 titer in the pretreatment and full-time experiments was analyzed by real-time PCR.

Data information: Error bars represent the standard deviation (SD), n=3. Statistical analysis was performed by unpaired two tail t-test. * P < 0,05, ** P < 0.01.
Humanized COVID-19 decoy antibody effectively blocks viral entry and prevents SARS-CoV-2 infection (2020)
Figure 6

Figure 6. Neutralization activity of ACE2-Fc on different SARS-CoV-2 strains. Yield reduction assay was performed to determine the inhibitory effects of ACE2-Fc on the entry of 5 different SARS-CoV-2 strains into Vero E6 cells.

(A) The (A) NP proteins in the cell lysates were determined by Western blot analysis.

(B, C) The virus RNA in the (B) culture medium and (C) cell lysates was quantified by real-time RT-PCR. The genetic information and sequence reference numbers for the 5 SARS-CoV-2 strains were summarized in Table EV1. Error bars represent the standard deviation (SD), n=3. Statistical analysis was performed by unpaired two tail t-test. ** P < 0.01, *** P < 0.001. Experiments were performed at least three times with similar results.
Humanized COVID-19 decoy antibody effectively blocks viral entry and prevents SARS-CoV-2 infection (2020)
Figure 7

Figure 7. Effects of ACE2-Fc on NK cell degranulation.

IL-2 activated NK cells were incubated with H1975-Spike cells at a 1:1 cell ratio in the presence of ACE2-Fc or ACE2. The activation of NK cell were determined by the CD107a, IFN-γ, and TNF-α expression levels.

(A) H1975 cells were transduced with full-length Spike by Lentiviral vector. Protein extracts were immunoblotted with the indicated antibodies. O/E represents overexpress.

(B) The effect of ACE2-Fc activation on degranulative capacity of NK cells. The experiments were performed with the primary human NK cells derived from three independent donors. Error bars represent the standard deviation (SD), n= 3. Statistical analysis was performed by unpaired two tail t-test. * P < 0.05 (each concentration of ACE2-Fc vs control).

(C) The CD107a, IFN-γ, and TNF-α expression levels were determined by flow cytometry after the NK cells and H1975-Spike cells coincubation in the presence or absence of ACE2-Fc or ACE2 control. Error bars represent the standard deviation (SD), n=3. Statistical analysis was performed by unpaired two tail t-test. * P < 0.05. The percentage of positive cells in both groups were normalized to the NK/H1975-Spike only group.

(D) The differential expression of degranulation markers after the treatment of ACE2-Fc or ACE2 by the flow cytometry. The numbers in each plot indicate the percentages of positive cells.
Identification of ROCK1 kinase as a critical regulator of Beclin1-mediated autophagy during metabolic stress (2013)
f1

(a) Identification of Beclin1 as a substrate of ROCK1 via affinity purification. Left panel: HeLa cells growing in control (C: nutrient-rich media) or starved in HBSS (H) for 4 h were lysed and subjected to IP with ROCK1 cross-linked beads. Proteins bound were eluted and detected by SDS–PAGE, followed by silver staining that presents precipitated proteins identified by LC-MS/MS. Right panel: HeLa cells grown in control media or HBSS (4 h) were collected, whole cell lysates prepared and immunoprecipitated with ROCK1 cross-linked beads. The resulting immune complexes were divided into two, and were subjected to SDS–PAGE and analysed for Beclin1 (MES buffer) and ROCK1 (MOPS buffer). Inputs and IP were analysed by western blotting. HBSS-treated cell extracts were used for IgG IP controls. Whole cell lysates (10%) were run for inputs. Total cell lysates were rerun and analysed for LC3 and β-actin. (b) Co-IP was performed with 293T whole cell extracts by using ROCK1-crosslinked agarose, and the resulting IP was blotted with indicated antibodies. 293T cells transfected with Flag-Beclin1 for 36 h, cultured in control media or starved (4 h), were immunoprecipitated with anti-Flag beads. Inputs and immune complexes were resolved and detected. Total cell lysates were rerun and examined for LC3 and β-actin expression. (c) Interaction of YFP-ROCK1 and CFP-Beclin1 was examined by using live cell spinning disk microscopy and FRET in live cells. Graph represents FRETAverage ratio changes (YFP-ROCK1/CFP-Beclin1) upon starvation. Data represents mean±s.e.m.; n=6. Three different experiments were performed. For the control, the right top graph represents CFP intensity over time (corrected for photobleach), and the right bottom right represents YFP intensity (corrected for photobleach). In both control FRET experiments, no significant change was observed in fluorescence, in the presence or absence of HBSS medium. P values were calculated using Student's t-test.
Identification of ROCK1 kinase as a critical regulator of Beclin1-mediated autophagy during metabolic stress (2013)
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(a) Inhibition of ROCK1 activity ablates the interaction between Beclin1 and ROCK1. HeLa cells were untreated (H2O) or treated with 10 μM ROCK1 inhibitor, Y27632, for 8 h and then cultured in control media (+) or HBSS (−) for 4 h. Cells were collected, lysed and immunoprecipitated with Beclin1 (left panel) or ROCK1 (right panel) antibody. Left panel: immune complexes were divided into two (ROCK1-MOPS buffer and Beclin1-MES buffer) and probed for ROCK1 and Beclin1. Relative values of ROCK1 versus Beclin1 are shown. (b) An increase in ROCK1-mediated phosphorylation of MYPT1 upon starvation. HeLa and EJ cells were starved in HBSS for indicated time points and endogenous ROCK1 was immunoprecipitated. An in vitro kinase assay was performed using MYPT1 as substrate and immune-complexed ROCK1. Proteins were resolved and visualized with Coomassie staining (top), western blot analysis (middle) and autoradiography (bottom). Inputs were examined for ROCK1 and β-actin. (c) HeLa cells incubated in HBSS were collected and endogenous phosphorylation of MYPT1 was determined by western blotting. The same blot was then washed in TBST for 30 min, blocked in 5% milk and was analysed for total MYPT1 as a control. Extracts from this experiment were rerun on 7.5% gel and analysed for ROCK1 and β-actin. (d) ROCK activity is increased upon starvation. Cell lines (HeLa and EJ) grown in control (+Glu) or starved with HBSS for 1 and 3 h were lysed, extracts normalized and ROCK kinase activity was measured by performing enzyme-linked immunosorbent assay. Graphs represent ROCK activity in starved cells plotted as percent of ROCK1 activity in control (glucose-rich) cells. Data were obtained from triplicates performed at the same time (mean±s.d.). P-value was calculated using Student’s t-test. (e) ROCK1 activity is not dependent on Beclin1. siControl (siCont.) and siBeclin1 knockdown cells were incubated in starvation media (HBSS) for indicated time. Resulting cell extracts were used to confirm Beclin1 knockdown and ROCK1 expression (left panel). Cell extracts from the same experiment were used for enzyme-linked immunosorbent assay measuring ROCK activity (right panel). Graph represents mean±s.d. of duplicate samples read at the same time (Student’s t-test; NS, not significant).
Identification of ROCK1 kinase as a critical regulator of Beclin1-mediated autophagy during metabolic stress (2013)
f3

(a) The effect of ROCK1 depletion on autophagy marker, LC3II. MEF ROCK1flox/flox cells were generated and treated with Con or Ad-Cre for 72 h. Cells were then incubated in nutrient-rich (+Glucose) or HBSS media for 2 h. Cell extracts were resolved by SDS–PAGE and ROCK1 KO was confirmed by western blotting (left panel). The same blot was used for LC3 and β-actin expression. Cells from the same experiment were fixed with chilled acetone and immunofluroscence was performed against endogenous LC3 (red). Blue represents nuclear DAPI staining. Scale bar, 20 μm. (b) EJ cells (left) with a stable knockdown using shCont. or shROCK1#1 were incubated in control (+glucose) or nutrient-free (HBSS) medium (−glucose) for 24 h and lysed. Lysates were subjected to western blotting with antibodies indicated. HeLa cells (right) with a transient knockdown using siCont. and siROCK1#2 for 30 h were further incubated in control or HBSS media for 8 h. Whole cell extracts were prepared, resolved by SDS–PAGE and analysed for ROCK1, LC3 and β-actin. Relative ratios of LC3II/LC3I are shown. (c) HeLa cells were treated with H2O or 10 μM ROCK1 inhibitor, Y27632, for 8 h. Cells were then cultured in high glucose (0 h) or starved for in HBSS nutrient-free media for 6 h. One hour before collection, cells were incubated in dimethylsulphoxide (control) or 0.1 μM bafilomycin-A1. Whole cell lysates were resolved by SDS–PAGE and were analysed by western blotting with indicated antibodies. (d) HeLa cells incubated with H2O or 10 μM Y27632 for 8 h were washed with PBS and cultured in control (+Glu) or HBSS media (−Glu) for an additional 8 h. Cells were fixed in acetone and immunofluorescence was performed against endogenous LC3 antibody (green). Scale bar, 20 μm. Graph represents % of LC3 punctae/cell (mean±s.d.), n=25 cells; (Student’s t-test) **P=0.00041. (e) Transmission electron micrographs of EJ cells with stable shCont. or shROCK1#1 knockdown, cultured in control or HBSS medium for 16 h. Arrow bars indicate autophagic vacuoles. Scale bar, 500 nm.