Protein: Peroxisome biogenesis protein 5 (Peroxin-5) (AtPEX5) (Peroxisomal targeting signal type 1 receptor) (Pex5p) (Q9FMA3)
Organism: Arabidopsis thaliana (Mouse-ear cress)
Function: Receptor that mediates peroxisomal import of proteins containing a C-terminal PTS1-type tripeptide peroxisomal targeting signal (SKL-type). Binds to cargo proteins containing a PTS1 peroxisomal targeting signal in the cytosol, and translocates them into the peroxisome matrix by passing through the PEX13-PEX14 docking complex along with cargo proteins. PEX5 receptor is then retrotranslocated into the cytosol, leading to release of bound cargo in the peroxisome matrix, and reset for a subsequent peroxisome import cycle (By similarity). In addition to promoting peroxisomal translocation of proteins containing a PTS1 peroxisomal targeting signal, mediates peroxisomal import of proteins containing a C-terminal PTS2-type peroxisomal targeting signal via its interaction with PEX7. Interaction with PEX7 only takes place when PEX7 is associated with cargo proteins containing a PTS2 peroxisomal targeting signal (By similarity). PEX7 along with PTS2-containing cargo proteins are then translocated through the PEX13-PEX14 docking complex together with PEX5 (By similarity). Necessary for the developmental elimination of obsolete peroxisome matrix proteins.
Subcellular location: Cytoplasm, cytosol {ECO:0000269|PubMed:16813573}. Peroxisome matrix {ECO:0000269|PubMed:16813573}. Note=Cycles between the cytosol and the peroxisome matrix (By similarity). Following binding to cargo proteins containing a PTS1 peroxisomal targeting signal in the cytosol, recruited to the docking complex, composed of PEX13 and PEX14, leading to translocation into the peroxisome matrix along with cargo proteins (By similarity). Export and recycling to the cytosol is initiated by binding to the PEX2-PEX10-PEX12 ligase complex via its unstructured N-terminus that inserts into the ligase pore and emerges in the cytosol (By similarity). Cys-13 of PEX5 is then monoubiquitinated, promoting its extraction from peroxisomal membrane by the PEX1-PEX6 AAA ATPase complex (By similarity). Extraction is accompanied by unfolding of the TPR repeats and release of bound cargo in the peroxisome matrix (By similarity). The TPR repeats refold in the cytosol and ubiquitination is removed by deubiquitinating enzymes, resetting PEX5 for a subsequent import cycle (By similarity). {ECO:0000250|UniProtKB:A0A1L8FDW4}.
Interaction partners:
- Peroxisome biogenesis protein 12
- Peroxisome biogenesis protein 7
- Peroxisome biogenesis factor 10
- Peroxisomal membrane protein PEX14
- Peroxisomal ATPase PEX6
- Protein NBR1 homolog
- Serine--glyoxylate aminotransferase
- Peroxisomal ATPase PEX1
- Peroxisomal acyl-coenzyme A oxidase 1
- Peroxisome biogenesis protein 16
Sequence:
MAMRDLVNGGAACAVPGSSSSSNPLGALTNALLGSSSKTQERLKEIPNANRSGPRPQFYSEDQQIRSLPGSELDQPLLQPGAQGSEFFRGFRSVDQNGLGAAWDEVQQGGPMPPMGPMFEPVQPTFEGPPQRVLSNFLHSFVESSRGGIPFRPAPVPVLGLSQSDKQCIRDRSSIMARHFFADRGEEFINSQVNALLSSLDIDDGIQARGHVPGRFRELDDYWNESQAVVKPNLHPADNWAAEFNQHGMDHGGPDSWVQSFEQQHGVNGWATEFEQGQSQLMSSQMRSMDMQNIAAMEQTRKLAHTLSQDGNPKFQNSRFLQFVSKMSRGELIIDENQVKQASAPGEWATEYEQQYLGPPSWADQFANEKLSHGPEQWADEFASGRGQQETAEDQWVNEFSKLNVDDWIDEFAEGPVGDSSADAWANAYDEFLNEKNAGKQTSGVYVFSDMNPYVGHPEPMKEGQELFRKGLLSEAALALEAEVMKNPENAEGWRLLGVTHAENDDDQQAIAAMMRAQEADPTNLEVLLALGVSHTNELEQATALKYLYGWLRNHPKYGAIAPPELADSLYHADIARLFNEASQLNPEDADVHIVLGVLYNLSREFDRAITSFQTALQLKPNDYSLWNKLGATQANSVQSADAISAYQQALDLKPNYVRAWANMGISYANQGMYKESIPYYVRALAMNPKADNAWQYLRLSLSCASRQDMIEACESRNLDLLQKEFPL