Prosaposin

PSAP
Available structures
PDB	Ortholog search: PDBe RCSB
List of PDB id codes
	1M12, 1N69, 1SN6, 2DOB, 2GTG, 2QYP, 2R0R, 2R1Q, 2RB3, 2Z9A, 3BQP, 3BQQ, 4DDJ, 4UEX, 4V2O
Identifiers
Aliases	PSAP, GLBA, SAP1, prosaposin, SAP2, PSAPD, PARK24
External IDs	OMIM: 176801; MGI: 97783; HomoloGene: 37680; GeneCards: PSAP; OMA:PSAP - orthologs
Gene location (Human)
Chr.	Chromosome 10 (human)
End	71,851,251 bp
Gene location (Mouse)
Chr.	Chromosome 10 (mouse)
End	60,138,376 bp
RNA expression pattern
	Top expressed in
	monocyte; ; tendon of biceps brachii; ; right adrenal cortex; ; gallbladder; ; internal globus pallidus; ; stromal cell of endometrium; ; Achilles tendon; ; left adrenal gland; ; visceral pleura; ; left adrenal cortex;
	Top expressed in
	stroma of bone marrow; ; gastrula; ; decidua; ; vestibular membrane of cochlear duct; ; choroid plexus of fourth ventricle; ; dentate gyrus of hippocampal formation granule cell; ; superior frontal gyrus; ; cerebellar cortex; ; mesenteric lymph nodes; ; primary visual cortex;
	More reference expression data
	; ;
	More reference expression data
Gene ontology
Molecular function	G protein-coupled receptor binding; protein binding; lipid binding; enzyme activator activity; beta-galactosidase activity; phospholipid binding; protein homodimerization activity; ganglioside GM1 binding; ganglioside GM2 binding; ganglioside GM3 binding; ganglioside GT1b binding; ganglioside GP1c binding; identical protein binding; protease binding;
Cellular component	lysosomal membrane; integral component of membrane; mitochondrion; lysosomal lumen; extracellular exosome; extracellular space; lysosome; plasma membrane; azurophil granule membrane; intracellular membrane-bounded organelle; extracellular matrix; extracellular region; cytoplasm; collagen-containing extracellular matrix; late endosome;
Biological process	lipid metabolism; lipid transport; epithelial cell differentiation involved in prostate gland development; regulation of MAPK cascade; glycosphingolipid metabolic process; developmental growth; adenylate cyclase-inhibiting G protein-coupled receptor signaling pathway; regulation of autophagy; positive regulation of MAPK cascade; cellular response to organic substance; negative regulation of hydrogen peroxide-induced cell death; regulation of lipid metabolic process; prostate gland growth; platelet degranulation; sphingolipid metabolic process; positive regulation of catalytic activity; neutrophil degranulation; ganglioside GM1 transport to membrane; corneocyte development; galactosylceramide catabolic process; G protein-coupled receptor signaling pathway; hearing; myelination; neuromuscular process controlling balance; positive regulation of hydrolase activity; urination; cochlea development; walking behavior; cornified envelope assembly; lysosomal transport;
	Sources:Amigo / QuickGO
Orthologs
	5660
	19156
	ENSG00000197746
	ENSMUSG00000004207
	P07602; Q5BJH1
	Q61207
	NM_002778; NM_001042465; NM_001042466
NM_001146120; NM_001146121; NM_001146122; NM_001146123; NM_001146124;
	NM_011179
	NP_001035930; NP_001035931; NP_002769; NP_002769.1
NP_001139592; NP_001139593; NP_001139594; NP_001139595; NP_001139596;
	NP_035309
	Wikidata
View/Edit Human	View/Edit Mouse

Prosaposin, also known as PSAP, is a protein which in humans is encoded by the PSAP gene.

This highly conserved glycoprotein 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 sphingolipids by specific lysosomal hydrolases.