Names & Taxonomy
- Uniprot ID:
- Q9Y4P1
- Entry Name:
- ATG4B_HUMAN
- Status:
- reviewed
- Protein Names:
- Cysteine protease ATG4B (EC 3.4.22.-) (AUT-like 1 cysteine endopeptidase) (Autophagin-1) (Autophagy-related cysteine endopeptidase 1) (Autophagy-related protein 4 homolog B) (hAPG4B)
- Gene Names:
- ATG4B APG4B AUTL1 KIAA0943
- Gene Names Primary:
- ATG4B
- Organism:
- Homo sapiens (Human)
Structure
- Length:
- 393
- Sequence:
- MDAATLTYDTLRFAEFEDFPETSEPVWILGRKYSIFTEKDEILSDVASRLWFTYRKNFPAIGGTGPTSDTGWGCMLRCGQMIFAQALVCRHLGRDWRWTQRKRQPDSYFSVLNAFIDRKDSYYSIHQIAQMGVGEGKSIGQWYGPNTVAQVLKKLAVFDTWSSLAVHIAMDNTVVMEEIRRLCRTSVPCAGATAFPADSDRHCNGFPAGAEVTNRPSPWRPLVLLIPLRLGLTDINEAYVETLKHCFMMPQSLGVIGGKPNSAHYFIGYVGEELIYLDPHTTQPAVEPTDGCFIPDESFHCQHPPCRMSIAELDPSIAVGFFCKTEDDFNDWCQQVKKLSLLGGALPMFELVELQPSHLACPDVLNLSLDSSDVERLERFFDSEDEDFEILSL
- Proteomes:
- UP000005640
Subcellular location
- Subcellular Location:
- Cytoplasm
Function
- Function:
- Cysteine protease required for the cytoplasm to vacuole transport (Cvt) and autophagy. Cleaves the C-terminal amino acid of ATG8 family proteins MAP1LC3, GABARAPL1, GABARAPL2 and GABARAP, to reveal a C-terminal glycine. Exposure of the glycine at the C-terminus is essential for ATG8 proteins conjugation to phosphatidylethanolamine (PE) and insertion to membranes, which is necessary for autophagy. Has also an activity of delipidating enzyme for the PE-conjugated forms.
- Kinetics:
- BIOPHYSICOCHEMICAL PROPERTIES: Kinetic parameters: KM=5.1 uM for MAP1LC3B
- Enzyme Regulation:
- ENZYME REGULATION: Inhibited by N-ethylmaleimide. Redox-regulated during autophagy since reducing conditions activate ATG4A whereas an oxidizing environment such as the presence of H(2)O(2) inhibits its activity.
- Active Site:
- ACT_SITE 74 74 Nucleophile.; ACT_SITE 278 278
- Gene Ontology Go:
- cytoplasm
cytosol
cysteine-type endopeptidase activity
cysteine-type peptidase activity
endopeptidase activity
autophagosome assembly
autophagy
C-terminal protein lipidation
macroautophagy
mitophagy
nucleophagy
positive regulation of protein catabolic process
protein delipidation
protein processing
protein targeting to membrane
proteolysis - Gene Ontology Biological Process:
- autophagosome assembly
autophagy
C-terminal protein lipidation
macroautophagy
mitophagy
nucleophagy
positive regulation of protein catabolic process
protein delipidation
protein processing
protein targeting to membrane
proteolysis - Gene Ontology Molecular Function:
- cysteine-type endopeptidase activity
cysteine-type peptidase activity
endopeptidase activity - Gene Ontology Cellular Component:
- cytoplasm
cytosol - Keywords:
- 3D-structure
Acetylation
Alternative splicing
Autophagy
Complete proteome
Cytoplasm
Direct protein sequencing
Hydrolase
Phosphoprotein
Polymorphism
Protease
Protein transport
Reference proteome
Thiol protease
Transport
Ubl conjugation pathway - Interacts With:
- O95166; Q9H0R8; P60520; Q9GZQ8