| IED ID | IndEnz0002014451 |
| Enzyme Type ID | protease014451 |
| Protein Name |
Cysteine protease ATG4 EC 3.4.22.- Autophagy-related protein 4 |
| Gene Name | ATG4 APG4 AUT2 YNL223W N1274 |
| Organism | Saccharomyces cerevisiae (strain ATCC 204508 / S288c) (Baker's yeast) |
| Taxonomic Lineage | cellular organisms Eukaryota Opisthokonta Fungi Dikarya Ascomycota saccharomyceta Saccharomycotina (true yeasts) Saccharomycetes Saccharomycetales Saccharomycetaceae Saccharomyces Saccharomyces cerevisiae (Baker's yeast) Saccharomyces cerevisiae (strain ATCC 204508 / S288c) (Baker's yeast) |
| Enzyme Sequence | MQRWLQLWKMDLVQKVSHGVFEGSSEEPAALMNHDYIVLGEVYPERDEESGAEQCEQDCRYRGEAVSDGFLSSLFGREISSYTKEFLLDVQSRVNFTYRTRFVPIARAPDGPSPLSLNLLVRTNPISTIEDYIANPDCFNTDIGWGCMIRTGQSLLGNALQILHLGRDFRVNGNESLERESKFVNWFNDTPEAPFSLHNFVSAGTELSDKRPGEWFGPAATARSIQSLIYGFPECGIDDCIVSVSSGDIYENEVEKVFAENPNSRILFLLGVKLGINAVNESYRESICGILSSTQSVGIAGGRPSSSLYFFGYQGNEFLHFDPHIPQPAVEDSFVESCHTSKFGKLQLSEMDPSMLIGILIKGEKDWQQWKLEVAESAIINVLAKRMDDFDVSCSMDDVESVSSNSMKKDASNNENLGVLEGDYVDIGAIFPHTTNTEDVDEYDCFQDIHCKKQKIVVMGNTHTVNANLTDYEVEGVLVEKETVGIHSPIDEKC |
| Enzyme Length | 494 |
| Uniprot Accession Number | P53867 |
| Absorption | |
| Active Site | ACT_SITE 147; /note=Nucleophile; /evidence=ECO:0000305|PubMed:11038174; ACT_SITE 322; /evidence=ECO:0000250|UniProtKB:Q9Y4P1; ACT_SITE 324; /evidence=ECO:0000250|UniProtKB:Q9Y4P1 |
| Activity Regulation | ACTIVITY REGULATION: Inhibited by N-ethylmaleimide. {ECO:0000269|PubMed:11038174}. |
| Binding Site | |
| Calcium Binding | |
| catalytic Activity | CATALYTIC ACTIVITY: Reaction=[protein]-C-terminal L-amino acid-glycyl-phosphatidylethanolamide + H2O = [protein]-C-terminal L-amino acid-glycine + a 1,2-diacyl-sn-glycero-3-phosphoethanolamine; Xref=Rhea:RHEA:67548, Rhea:RHEA-COMP:17323, Rhea:RHEA-COMP:17324, ChEBI:CHEBI:15377, ChEBI:CHEBI:64612, ChEBI:CHEBI:172940, ChEBI:CHEBI:172941; Evidence={ECO:0000269|PubMed:22240591, ECO:0000269|PubMed:22652539};PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:67549; Evidence={ECO:0000269|PubMed:22240591, ECO:0000269|PubMed:22652539}; |
| DNA Binding | |
| EC Number | 3.4.22.- |
| Enzyme Function | FUNCTION: Cysteine protease that plays a key role in cytoplasm to vacuole transport (Cvt) and autophagy by mediating both proteolytic activation and delipidation of ATG8 (PubMed:11038174, PubMed:11100732, PubMed:11149920, PubMed:11904149, PubMed:16680092, PubMed:18701704, PubMed:18725539, PubMed:8050581, PubMed:8224160, PubMed:9649430, PubMed:28330855, PubMed:28821724, PubMed:28704456). Required for selective autophagic degradation of the nucleus (nucleophagy) as well as for mitophagy which contributes to regulate mitochondrial quantity and quality by eliminating the mitochondria to a basal level to fulfill cellular energy requirements and preventing excess ROS production (PubMed:11038174, PubMed:11100732, PubMed:11149920, PubMed:11904149, PubMed:16680092, PubMed:18701704, PubMed:18725539, PubMed:8050581, PubMed:8224160, PubMed:9649430). The protease activity is required for proteolytic activation of ATG8: cleaves the C-terminal amino acid of ATG8 to reveal a C-terminal glycine (PubMed:11038174, PubMed:11100732, PubMed:11149920, PubMed:11904149, PubMed:16680092, PubMed:18701704, PubMed:18725539, PubMed:8050581, PubMed:8224160, PubMed:9649430). ATG8 ubiquitin-like activity requires the exposure of the glycine at the C-terminus for its conjugation to phosphatidylethanolamine (PE) and its insertion to membranes, which is necessary for autophagy (PubMed:11038174, PubMed:11100732, PubMed:11149920, PubMed:11904149, PubMed:16680092, PubMed:18701704, PubMed:18725539, PubMed:8050581, PubMed:8224160, PubMed:9649430). The ATG8-PE conjugate mediates tethering between adjacent membranes and stimulates membrane hemifusion, leading to expansion of the autophagosomal membrane during autophagy (PubMed:17632063). In addition to the protease activity, also catalyzes deconjugation of PE-conjugated forms of ATG8 during macroautophagy: ATG8 delipidation is required to release the protein from membranes, which facilitates multiple events during macroautophagy, and especially for efficient autophagosome biogenesis, the assembly of ATG9-containing tubulovesicular clusters into phagophores/autophagosomes, and for the disassembly of PAS-associated ATG components (PubMed:22240591, PubMed:22652539, PubMed:28330855, PubMed:28821724, PubMed:28704456). ATG8 delipidation by ATG4 also recycles ATG8-PE generated on inappropriate membranes to maintain a reservoir of unlipidated ATG8 that is required for autophagosome formation at the PAS (PubMed:22240591, PubMed:22652539). {ECO:0000269|PubMed:11038174, ECO:0000269|PubMed:11100732, ECO:0000269|PubMed:11149920, ECO:0000269|PubMed:11904149, ECO:0000269|PubMed:16680092, ECO:0000269|PubMed:17632063, ECO:0000269|PubMed:18701704, ECO:0000269|PubMed:18725539, ECO:0000269|PubMed:22240591, ECO:0000269|PubMed:22652539, ECO:0000269|PubMed:28330855, ECO:0000269|PubMed:28704456, ECO:0000269|PubMed:28821724, ECO:0000269|PubMed:8050581, ECO:0000269|PubMed:8224160, ECO:0000269|PubMed:9649430}. |
| Temperature Dependency | |
| PH Dependency | |
| Pathway | |
| nucleotide Binding | |
| Features | Active site (3); Chain (1); Disulfide bond (1); Erroneous initiation (2); Modified residue (2); Motif (2); Mutagenesis (11) |
| Keywords | Autophagy;Cytoplasm;Disulfide bond;Hydrolase;Isopeptide bond;Nucleus;Phosphoprotein;Protease;Protein transport;Reference proteome;Thiol protease;Transport;Ubl conjugation pathway |
| Interact With | P38182 |
| Induction | INDUCTION: Expression is induced upon starvation, through the action of transcription factors GCN2 and GCN4. {ECO:0000269|PubMed:20647741}. |
| Subcellular Location | SUBCELLULAR LOCATION: Cytoplasm {ECO:0000269|PubMed:11149920}. Nucleus {ECO:0000269|PubMed:14562095}. Preautophagosomal structure {ECO:0000269|PubMed:25483965, ECO:0000269|PubMed:28330855, ECO:0000269|PubMed:28821724}. |
| Modified Residue | MOD_RES 307; /note="Phosphoserine; by ATG1"; /evidence="ECO:0000269|PubMed:28821724"; MOD_RES 488; /note="Phosphoserine"; /evidence="ECO:0007744|PubMed:18407956, ECO:0007744|PubMed:19779198" |
| Post Translational Modification | PTM: Phosphorylation at Ser-307 by ATG1 inhibits autophagy: it takes place on autophagosome membranes and decreases its interaction with ATG8, thereby impairing deconjugation of PE-conjugated forms of ATG8. {ECO:0000269|PubMed:28821724}.; PTM: Formation of a disulfide bond between Cys-338 and Cys-394 leads to reduced autophagy (PubMed:25483965). The disulfide bond is reduced by thioredoxin (PubMed:25483965). {ECO:0000269|PubMed:25483965}. |
| Signal Peptide | |
| Structure 3D | |
| Cross Reference PDB | - |
| Mapped Pubmed ID | 10525546; 10649453; 11086004; 11099404; 11139573; 11169858; 11486014; 11528006; 11689437; 11805837; 11995965; 15140988; 15178341; 15350980; 15615779; 16230342; 16247502; 16429126; 16860663; 17204848; 17224625; 17382324; 17890363; 17909521; 18006683; 18039653; 18719252; 19079287; 19491929; 19535904; 19536198; 19619494; 19653858; 19659885; 19744312; 19793921; 19923912; 19941614; 20083110; 20124347; 20146925; 20184884; 20223289; 20487284; 20712412; 20811355; 21194379; 21315770; 21317551; 21404646; 21548784; 21801009; 22150273; 22240478; 22257882; 22399380; 22480867; 22489171; 22536249; 22550491; 22661635; 22722653; 22768199; 22782902; 22992453; 23064313; 23416930; 23545414; 23669359; 23733851; 23750326; 23943849; 24121596; 24258026; 24366339; 24366340; 24462201; 24485455; 24710476; 24789822; 24879146; 24914435; 24928445; 25426852; 25484070; 25500271; 25568152; 25654548; 25691244; 25747593; 25759175; 26081468; 26108642; 26344037; 26438722; 26490118; 26908221; 27189367; 27381245; 27957648; 8663607; 8901576; |
| Motif | MOTIF 102..105; /note="APEAR"; /evidence="ECO:0000269|PubMed:28330855"; MOTIF 424..427; /note="LIR"; /evidence="ECO:0000269|PubMed:28287329, ECO:0000269|PubMed:28330855" |
| Gene Encoded By | |
| Mass | 55,143 |
| Kinetics | |
| Metal Binding | |
| Rhea ID | RHEA:67548; RHEA:67549 |
| Cross Reference Brenda |