Protein: Calcium-dependent secretion activator (Calcium-activated protein for secretion) (Q9NHE5)
Organism: Drosophila melanogaster (Fruit fly)
Function: Calcium-binding protein involved in exocytosis of vesicles filled with neurotransmitters and neuropeptides. May specifically mediate the Ca(2+)-dependent exocytosis of large dense-core vesicles (DCVs) and other dense-core vesicles. However, it probably also participates in small clear synaptic vesicles (SVs) exocytosis and it is unclear whether its function is related to Ca(2+) triggering.
Subcellular location: Cytoplasmic vesicle membrane {ECO:0000269|PubMed:11516399}. Synapse {ECO:0000269|PubMed:11516399}. Note=Membrane-associated to vesicles. Restricted to all classes of presynaptic termini independent of the ratio of vesicular content (dense core vesicles versus synaptic vesicles). Found in all identified classes of peripheral and central synapses. In the CNS, it is highly enriched in the synapse-dense neuropil, which lacks cell bodies. Present in all synapses in the neuropil where it precisely colocalizes with other pansynaptic markers. Similarly abundant in all classes of neuromuscular junction (NMJ) termini, including type I, II, and III NMJs, where it localizes to all 3 bouton types. Expressed at similar levels in boutons which contain primarily small clear glutamatergic vesicles, as well as boutons very highly enriched in large DCVs. It appears that neither bouton class contains a pure population of either SVs or DCVs, but only differs dramatically in the relative abundance of the vesicular classes. Thus, the level of expression does not correlate with the abundance of DCVs. Clearly present presynaptically and colocalizes exclusively with presynaptic markers. {ECO:0000269|PubMed:11516399}.
Interaction partners:
- Unc-13, isoform E
Sequence:
MIDPSSSEEEGEDDAVPNVSSKGRLTNTTKGTSAVSIIGGSAGSVVGSNIPVSGSNTDLIGNQRQSNISSICNRNDVGNISVAALGSTSNKIEQICGNRADTGNLEVPSNGIPSGISQETLNQSVGSSRANSLPRPLSPSPSLTSEKHETAEPHGKHEREEEERKRRIQLYVFISRCISYPFNAKQPTDMTKRQTKISKQQLEIITQRFQAFLKGETQIMADEAFQNAVQSYHDVFLKSERVLKMVQSGASSQHDFREVFRNNIEKRVRSLPEIDGLSKETVLTSWMAKFDIILKGTGEEDSKRPSRMQQSLNSELILSKEQLYDMFQQILLVKKFEHQILFNALMLDSADEQAAAIRRELDGRMQRVGEMEKNRKLMPKFVLKEMESLYVEELKSSINLLMANLESLPVSKGNMDSKYGLQKLKRYNHSTPSFLKLILRSHGSLSKLEGDSEDGSTQLTKLDVVLTFQLEVIVMEVENGEKLQTDQAEASKPMWDTQGDFTTTHPLPVVKVKLYTENPGMLALEDKELGKVTLKPTPLSSKSPEWHRMIVPKNLPDQDIRIKIACRLDKPLNMKHCGYLYAIGKSVWKKWKRRYFVLVQVSQYTFAMCSYKEKKSEPSEMMQLDGYTVDYIEAASANLMFGIDLNGGRYFFNAVREGDSISFACDDENECSLWVMAMYRATGQSHKPTPPITQDKNSAMSKIQGDADKARKHGMEDFISTDPCTFDHATLFKTLQNLTLEYRLNDPYASLGWFSPGQVFVLDEYCARYGVRGCYRHLCYLSDLLDRAEKQHMIDPTLIHYSFAFCASHVHGNRPDGVGSITHEEKEKFSEIKERLRQLLEFQITNFRYCFPFGRPEGALKATLSLLERVLMKDIVTPVPPEEVRQMIKKSLETAALVNYTRLSNKAKIDEDLRGDVIVPAPKKLEDLIHLAELCVDLLQQNEEHYGEAFAWFSDLLVEHAEIFWSLFAVDMDRVLSEQAPDTWDSFPLFQILNDYLRTDDNLRNGRFHQHLRDTFAPLVVRYVDLMESSIAQSIHKGFEKERWESKGINAALNPAALNNAAQALNTAALNPSMILCGKKDQVNFYVPKLPKQSNSTAANDEMRNGCATSEDLFWKLDALQSFIRDLHWPDAEFRQHLEQRLKMMAVDMIEQCIQRTDSSFQSWLKKNIAFISTDYILPSEMCAMVNVILDAKNQSFKLTTIDGIDLYKFHAKIDDQIDKANVAMTQGLSGKLMSVLESTLSKLARYDEGSLIGSILSFTNVSSSGKDLGQGYVNFFRNNMDQVRGKIADDLWTLHFFEQWYSQQINMLCNWLSERVDHALHYAQVASISHIIKKIYSDFELQGVLEDKLNSKAYQAVAQRMATEEATCALTMPDACEDEPCDEIREGEEEDNGDESTSNIPRGLPKPKVAAAQAAAVTNVVAGRVGNLLGKGIGGLSSKLGSGSWF