Protein: Testis-expressed protein 264 homolog (E9Q137)
Organism: Mus musculus (Mouse)
Function: Major reticulophagy (also called ER-phagy) receptor that acts independently of other candidate reticulophagy receptors to remodel subdomains of the endoplasmic reticulum into autophagosomes upon nutrient stress, which then fuse with lysosomes for endoplasmic reticulum turnover. The ATG8-containing isolation membrane (IM) cradles a tubular segment of TEX264-positive ER near a three-way junction, allowing the formation of a synapse of 2 juxtaposed membranes with trans interaction between the TEX264 and ATG8 proteins. Expansion of the IM would extend the capture of ER, possibly through a 'zipper-like' process involving continued trans TEX264-ATG8 interactions, until poorly understood mechanisms lead to the fission of relevant membranes and, ultimately, autophagosomal membrane closure. Also involved in the repair of covalent DNA-protein cross-links (DPCs) during DNA synthesis: acts by bridging VCP/p97 to covalent DNA-protein cross-links (DPCs) and initiating resolution of DPCs by SPRTN.
Subcellular location: Endoplasmic reticulum membrane {ECO:0000250|UniProtKB:Q9Y6I9}; Single-pass type III membrane protein {ECO:0000250|UniProtKB:Q9Y6I9}. Cytoplasmic vesicle, autophagosome {ECO:0000250|UniProtKB:Q9Y6I9}. Cytoplasm, cytosol {ECO:0000250|UniProtKB:Q9Y6I9}. Nucleus {ECO:0000250|UniProtKB:Q9Y6I9}. Chromosome {ECO:0000250|UniProtKB:Q9Y6I9}. Note=Is trafficked from tubular ER to growing autophagosomes via its cytosolic LIR motif. Also found in the cytosol, nucleus and chromatin. In response to formation of covalent DNA-protein cross-links (DPCs), localizes to the nuclear periphery, and associates with DNA replication forks. {ECO:0000250|UniProtKB:Q9Y6I9}.
Sequence: MPDLLLLGLIGALTLLLLLTLLAFAGYSGLLTGVTVSAGSPPIRNITVAYKFHVGSYGDTGHLFTESCSISPKLRSIAVYYDNPHTVPPEKCRCAVGSILSEGEESPSPELIHLYQKFGFKIFSFPAPSHVVIATFPYTTPISIWLAARRVHPALDTYIKERKLCAHPRLEIYHQDKIHFMCPLARQGDFYVPEVKETERKCRELAEATDTQTDGTGADTSDASSVSLDVRPGSRETSATTLSPGAGNRGWDDGDNRSEHSYSESGASGSSFEELDLEGEGPLGEPRLNPEAKLLGPPRELSTPERGEE
InterPro domains: - IPR011256: Regulatory factor, effector binding domain superfamily (homologous_superfamily) [42-193]
Interaction partners: - Cell cycle progression protein 1
- Atlastin-3
- Translocation protein SEC62
- Reticulophagy regulator 1
- Reticulon-3
- Gamma-aminobutyric acid receptor-associated protein
Gene Ontology annotations:
Molecular Function (MF): GO:0003674 (molecular function), GO:0005488 (binding), GO:0060089 (molecular transducer activity), GO:0038023 (signaling receptor activity), GO:0005515 (protein binding)
Biological Process (BP): GO:0008150 (biological process), GO:0008152 (metabolic process), GO:0050896 (response to stimulus), GO:0009987 (cellular process), GO:0044237 (cellular metabolic process), GO:0006807 (nitrogen compound metabolic process), GO:0051716 (cellular response to stimulus), GO:0071840 (cellular component organization or biogenesis), GO:0006950 (response to stress), GO:0061919 (process utilizing autophagic mechanism), GO:0071704 (organic substance metabolic process), GO:0009056 (catabolic process), GO:0044238 (primary metabolic process), GO:1901360 (organic cyclic compound metabolic process), GO:0006139 (nucleobase-containing compound metabolic process), GO:0046483 (heterocycle metabolic process), GO:0033554 (cellular response to stress), GO:0044248 (cellular catabolic process), GO:0016043 (cellular component organization), GO:0006725 (cellular aromatic compound metabolic process), GO:0034641 (cellular nitrogen compound metabolic process), GO:0044260 (cellular macromolecule metabolic process), GO:0043170 (macromolecule metabolic process), GO:0006914 (autophagy), GO:0016236 (macroautophagy), GO:0090304 (nucleic acid metabolic process), GO:0006974 (cellular response to DNA damage stimulus), GO:0006259 (DNA metabolic process), GO:0006996 (organelle organization), GO:0022411 (cellular component disassembly), GO:0061912 (selective autophagy), GO:0006281 (DNA repair), GO:1903008 (organelle disassembly), GO:0061709 (reticulophagy)
Cellular Component (CC): GO:0005575 (cellular component), GO:0110165 (cellular anatomical entity), GO:0005622 (intracellular anatomical structure), GO:0043226 (organelle), GO:0016020 (membrane), GO:0005737 (cytoplasm), GO:0012505 (endomembrane system), GO:0031984 (organelle subcompartment), GO:0042175 (nuclear outer membrane-endoplasmic reticulum membrane network), GO:0031090 (organelle membrane), GO:0005783 (endoplasmic reticulum), GO:0043229 (intracellular organelle), GO:0043227 (membrane-bounded organelle), GO:0098827 (endoplasmic reticulum subcompartment), GO:0043231 (intracellular membrane-bounded organelle), GO:0005789 (endoplasmic reticulum membrane)