SYTL2 Antibody – Rabbit Polyclonal

The protein encoded by this gene is a synaptotagmin-like protein (SLP) that belongs to a C2 domain-containing protein family. The SLP homology domain (SHD) of this protein has been shown to specifically bind the GTP-bound form of Ras-related protein Rab-27A (RAB27A). This protein plays a role in RAB27A-dependent vesicle trafficking and controls melanosome distribution in the cell periphery. Alternative splicing results in multiple transcript variants encoding distinct isoforms.[provided by RefSeq, Jun 2009]

Function: Isoform 1 acts as a RAB27A effector protein and plays a role in cytotoxic granule exocytosis in lymphocytes. It is required for cytotoxic granule docking at the immunologic synapse. Isoform 4 binds phosphatidylserine (PS) and phosphatidylinositol-4,5-bisphosphate (PIP2) and promotes the recruitment of glucagon-containing granules to the cell membrane in pancreatic alpha cells. Binding to PS is inhibited by Ca2+ while binding to PIP2 is Ca2+ insensitive. Ref.1 Ref.9 Ref.10

Subunit structure: Monomer. Binds NRXN1. Interacts with RAB27B

By similarity. Binds RAB27A that has been activated by GTP-binding. Ref.1 Ref.11

Subcellular location: Isoform 1: Cytoplasm. Cell membrane. Note: Recruited on vesicular structures in cytotoxic T-lymphocytes (CTL) by RAB27A. Ref.1 Ref.9 Ref.10Isoform 4: Cell membrane. Note: In the pancreatic alpha cells distributed in both peripheral and anterior regions. Localizes on the glucagon granules in the cell periphery. Ref.1 Ref.9 Ref.10

Tissue specificity: Isoform 1 is expressed in hematopoietic lineages with a strong expression in CD4 and CD8 T-lymphocytes. It is also widely expressed in nonhematopoietic tissues. Isoform 5 is expressed only in nonhematopoietic tissues. Isoform 4 is expressed in pancreatic alpha cells. Ref.1 Ref.9 Ref.10

Domain: The RabBD domain mediates interaction with RAB27A and recruitment on to vesicular structures in cytotoxic T-lymphocytes (CTL). Ref.1 Ref.9The C2 1 domain mediates binding to phosphatidylserine (PS) and phosphatidylinositol 4,5-bisphosphate (PIP2) and localization to the cell membrane. Ref.1 Ref.9

Post-translational modification: Isoform 1 is highly susceptible to proteolytic degradation and is stabilized by the interaction with RAB27A.

Sequence similarities: Contains 2 C2 domains.Contains 1 RabBD (Rab-binding) domain.

Sequence caution: The sequence AAR25619.1 differs from that shown. Reason: Erroneous initiation. Translation N-terminally shortened.The sequence BAA90989.1 differs from that shown. Reason: Probable cloning artifact.The sequence BAB13423.1 differs from that shown. Reason: Erroneous initiation. Translation N-terminally extended.The sequence BAB13423.1 differs from that shown. Reason: Frameshift at position 13. The sequence BAB13423.1 differs from that shown. Reason: Sequencing errors.The sequence BAD18516.1 differs from that shown. Reason: Erroneous initiation. Translation N-terminally extended.