Exocyst Complex Component 3 Like Protein 4 (EXOC3L4)

EXOC3L4 belongs to the SEC6 family. Sec6 is the core subunit of the exocyst complex. An isoform of Sec6, deposited as Exocyst complex component 3-like (Exoc3l) in the database, by in silico screening using rat Sec6 as a probe. The amino acid sequence of Exoc3l has 31% identity and 53% similarity with that of Sec6. RT-PCR analysis reveals that Exoc3l is expressed in insulin-secreting MIN6 cells as well as in various tissues including pancreatic islets and brain. In co-immunoprecipitation experiments, Exoc3l was found to interact with Sec5, Sec8, and Sec10, all of which are binding partners of Sec6 in the exocyst complex. Furthermore, overexpression of a deletion mutant of Exoc3l in MIN6 cells suppressed glucose-stimulated secretion. Exoc3l is involved in regulated exocytosis of insulin granules.