SNAPIN
Developmental stage
Expressed in germ cells of 22-week prenatal testis.
Function
Component of the BLOC-1 complex, a complex that is required for normal biogenesis of lysosome-related organelles (LRO), such as platelet dense granules and melanosomes. In concert with the AP-3 complex, the BLOC-1 complex is required to target membrane protein cargos into vesicles assembled at cell bodies for delivery into neurites and nerve terminals. The BLOC-1 complex, in association with SNARE proteins, is also proposed to be involved in neurite extension. Plays a role in intracellular vesicle trafficking and synaptic vesicle recycling. May modulate a step between vesicle priming, fusion and calcium-dependent neurotransmitter release through its ability to potentiate the interaction of synaptotagmin with the SNAREs and the plasma-membrane-associated protein SNAP25. Its phosphorylation state influences exocytotic protein interactions and may regulate synaptic vesicle exocytosis. May also have a role in the mechanisms of SNARE-mediated membrane fusion in non-neuronal cells (PubMed:17182842, PubMed:18167355). As part of the BORC complex may play a role in lysosomes movement and localization at the cell periphery. Associated with the cytosolic face of lysosomes, the BORC complex may recruit ARL8B and couple lysosomes to microtubule plus-end-directed kinesin motor (PubMed:25898167).
Post-translational modifications
Phosphorylated by CSNK1D/CK1 (By similarity). Phosphorylated by PKD, phosphorylation controls SNAPIN protein stability.
Sequence Similarities
Belongs to the SNAPIN family.
Tissue Specificity
Expressed in male germ cells of adult testis (at protein level).
Cellular localization
- Membrane
- Peripheral membrane protein
- Cytoplasmic side
- Cytoplasm
- Cytosol
- Cytoplasm
- Perinuclear region
- Golgi apparatus membrane
- Lysosome membrane
- Cytoplasmic vesicle
- Secretory vesicle
- Synaptic vesicle membrane
- Colocalizes with NANOS1 and PUM2 in the perinuclear region of germ cells.
Alternative names
BLOC1S7, SNAP25BP, SNAPAP, SNAPIN, SNARE-associated protein Snapin, Biogenesis of lysosome-related organelles complex 1 subunit 7, Synaptosomal-associated protein 25-binding protein, BLOC-1 subunit 7, SNAP-associated protein