Synaptotagmin XIII (SYT13)

SYT13 belongs to the large synaptotagmin protein family. All synaptotagmins show type I membrane topology, with an extracellular N terminus, a single transmembrane region, and a cytoplasmic C terminus containing tandem C2 domains. Major functions of synaptotagmins include vesicular traffic, exocytosis, and secretion. The deduced 439-amino acid protein shares 32% identity with mouse Syt1. RT-PCR ELISA detected moderate expression in adult and fetal brain and kidney, as well as in all adult brain regions tested. SYT13 was expressed at lower levels in heart, testis, and spinal cord, but was not expressed in lung, liver, skeletal muscle, pancreas, spleen, or fetal liver.The deduced 426-amino acid protein has a calculated molecular mass of about 47 kD and shares 90% identity with human SYT13.