synaptotagmin-1; synaptotagmin I; SytI; p65 (SYT1 SVP65 SYT)

Function

• may have a regulatory role in the membrane interactions during trafficking of synaptic vesicles at the active zone of the synapse
• possibly couples secretion to neuronal activity
• component of the neuronal secretory machinary
• binds acidic phospholipids with a specificity that requires both an acidic headgroup & a diacyl backbone
• facilitates actin-dependent filopodial extension of neurites
• Ca+2-dependent interaction between synaptotagmin & putative receptors for activated protein kinase C has been reported
• Ca+2-independent binding of neurexins, syntaxin & HA2/AP2 adaptor complex
• binds 3 Ca+2 per subunit via C2 domains
• interacts with SCAMP5, STN2, SV2A, SV2B, SV2C & RIMS1
• forms a complex with SV2B, syntaxin 1 & SNAP25 (putative)

Structure

• homotetramer (probable).
• the first C2 domain mediates Ca+2-dependent phospholipid binding
• the second C2 domain mediates interaction with SV2A & STN2 (putative)
• belongs to the synaptotagmin family
• contains 2 C2 domains

Compartment

• cytoplasmic vesicle, secretory vesicle,
• synaptic vesicle membrane
• cytoplasmic vesicle, secretory vesicle,
• chromaffin granule membrane
• cytoplasm
• synaptic vesicles & chromaffin granules

Comparative biology

• no yeast counterpart

More general terms

• synaptotagmin

Database

• UniProt: http://www.uniprot.org/uniprot/P21579.html
• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=6857
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:6857
• OMIM: https://mirror.omim.org/entry/185605