Prosaposin (PSAP)

SAP1; GLBA; CSAct; Dispersin; Pro-Saposin; Proactivator polypeptide; Glucosylceramidase activator; Sulfatide/GM1 activator; Cerebroside sulfate activator; Sphingolipid Activator 1

SPN	U101
HGNC	9498
MGI	97783
PubMed	15743835
RGD	3423
UniProt	P07602
Wiki	Prosaposin

Prosaposin also known as PSAP is a highly conserved glycoprotein which is a precursor for 4 cleavage products: saposins A, B, C, and D. Saposin is an acronym for Sphingolipid Activator PrO[S]teINs. Each domain of the precursor protein is approximately 80 amino acid residues long with nearly identical placement of cysteine residues and glycosylation sites. Saposins A-D localize primarily to the lysosomal compartment where they facilitate the catabolism of glycosphingolipids with short oligosaccharide groups. The precursor protein exists both as a secretory protein and as an integral membrane protein and has neurotrophic activities.Saposins A-D are required for the hydrolysis of certain shingolipids by specific lysosomal hydrolases.

Reference

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