Protein: Signal recognition particle receptor subunit alpha homolog (SR-alpha) (Docking protein alpha) (DP-alpha) (P32916)
Organism: Saccharomyces cerevisiae (strain ATCC 204508 / S288c) (Baker's yeast)
Function: Component of the SRP (signal recognition particle) receptor (SR). Ensures, in conjunction with the signal recognition particle, the correct targeting of the nascent secretory proteins to the endoplasmic reticulum membrane system. GTP hydrolysis may enhance the fidelity of and provide unidirectionality to the targeting reaction. It is important but not essential for cell growth. May be directly involved in mitochondrial protein import.
Subcellular location: Endoplasmic reticulum membrane {ECO:0000269|PubMed:1327299}; Peripheral membrane protein {ECO:0000269|PubMed:1327299}; Cytoplasmic side {ECO:0000269|PubMed:1327299}. Note=Thought to be anchored in the membrane through an interaction with SRP102/SR-beta, which contains a bona fide transmembrane domain. {ECO:0000269|PubMed:1327299}.
Sequence: MFDQLAVFTPQGQVLYQYNCLGKKFSEIQINSFISQLITSPVTRKESVANANTDGFDFNLLTINSEHKNSPSFNALFYLNKQPELYFVVTFAEQTLELNQETQQTLALVLKLWNSLHLSESILKNRQGQNEKNKHNYVDILQGIEDDLKKFEQYFRIKYEESIKQDHINPDNFTKNGSVPQSHNKNTKKKLRDTKGKKQSTGNVGSGRKWGRDGGMLDEMNHEDAAKLDFSSSNSHNSSQVALDSTINKDSFGDRTEGGDFLIKEIDDLLSSHKDEITSGNEAKNSGYVSTAFGFLQKHVLGNKTINESDLKSVLEKLTQQLITKNVAPEAADYLTQQVSHDLVGSKTANWTSVENTARESLTKALTQILTPGVSVDLLREIQSKRSKKDEEGKCDPYVFSIVGVNGVGKSTNLSKLAFWLLQNNFKVLIVACDTFRSGAVEQLRVHVENLAQLMDDSHVRGSKNKRGKTGNDYVELFEAGYGGSDLVTKIAKQAIKYSRDQNFDIVLMDTAGRRHNDPTLMSPLKSFADQAKPDKIIMVGEALVGTDSVQQAKNFNDAFGKGRNLDFFIISKCDTVGEMLGTMVNMVYATGIPILFVGVGQTYTDLRTLSVKWAVNTLMS
InterPro domains: - IPR015284: Signal recognition particle (SRP) receptor alpha subunit, N-terminal (domain) [1-155]
- IPR000897: Signal recognition particle, SRP54 subunit, GTPase domain (domain) [397-621]
- IPR042101: Signal recognition particle SRP54, N-terminal domain superfamily (homologous_superfamily) [264-372]
- IPR003593: AAA+ ATPase domain (domain) [396-557]
- IPR036225: SRP/SRP receptor, N-terminal (homologous_superfamily) [294-372]
- IPR011012: Longin-like domain superfamily (homologous_superfamily) [1-155]
- IPR027417: P-loop containing nucleoside triphosphate hydrolase (homologous_superfamily) [375-621]
- IPR013822: Signal recognition particle SRP54, helical bundle (domain) [288-370]
Interaction partners: - Signal recognition particle receptor subunit beta
- Signal recognition particle subunit SRP54
- Signal recognition particle subunit SRP72
- Signal recognition particle subunit SRP68
- Signal recognition particle subunit SEC65
- Large ribosomal subunit protein uL23
- Signal recognition particle subunit SRP21
- Large ribosomal subunit protein uL18
- Protein transport protein SEC61
- Signal recognition particle subunit SRP14
Gene Ontology annotations:
Molecular Function (MF): GO:0003674 (molecular function), GO:0005488 (binding), GO:0097159 (organic cyclic compound binding), GO:1901363 (heterocyclic compound binding), GO:0003676 (nucleic acid binding), GO:0003723 (RNA binding)
Biological Process (BP): GO:0008150 (biological process), GO:0009987 (cellular process), GO:0051179 (localization), GO:0051234 (establishment of localization), GO:0051641 (cellular localization), GO:0033036 (macromolecule localization), GO:0070727 (cellular macromolecule localization), GO:0051649 (establishment of localization in cell), GO:0046907 (intracellular transport), GO:0051668 (localization within membrane), GO:0045184 (establishment of protein localization), GO:0006810 (transport), GO:0071702 (organic substance transport), GO:0006886 (intracellular protein transport), GO:0071705 (nitrogen compound transport), GO:0008104 (protein localization), GO:0015031 (protein transport), GO:0072594 (establishment of protein localization to organelle), GO:0090150 (establishment of protein localization to membrane), GO:0072657 (protein localization to membrane), GO:0033365 (protein localization to organelle), GO:0006612 (protein targeting to membrane), GO:0006605 (protein targeting), GO:0072599 (establishment of protein localization to endoplasmic reticulum), GO:0045047 (protein targeting to ER), GO:0070972 (protein localization to endoplasmic reticulum), GO:0006613 (cotranslational protein targeting to membrane), GO:0006614 (SRP-dependent cotranslational protein targeting to membrane)
Cellular Component (CC): GO:0005575 (cellular component), GO:0032991 (protein-containing complex), GO:0110165 (cellular anatomical entity), GO:0005622 (intracellular anatomical structure), GO:0043226 (organelle), GO:0140534 (endoplasmic reticulum protein-containing complex), GO:0016020 (membrane), GO:0098796 (membrane protein complex), GO:0031984 (organelle subcompartment), GO:0005737 (cytoplasm), GO:0012505 (endomembrane system), GO:0031090 (organelle membrane), GO:0043229 (intracellular organelle), GO:0098827 (endoplasmic reticulum subcompartment), GO:0042175 (nuclear outer membrane-endoplasmic reticulum membrane network), GO:0005783 (endoplasmic reticulum), GO:0043227 (membrane-bounded organelle), GO:0043231 (intracellular membrane-bounded organelle), GO:0098588 (bounding membrane of organelle), GO:0005791 (rough endoplasmic reticulum), GO:0005789 (endoplasmic reticulum membrane), GO:0030867 (rough endoplasmic reticulum membrane)