Function
Acts as a lysosomal activator protein that stimulates acid ceramidase (EC 3.5.1.23) by solubilizing and presenting ceramide substrates at the lipid-water interface, facilitating their hydrolysis into sphingosine and fatty acids. It also activates acid sphingomyelinase (EC 3.1.4.12), though ceramide catabolism represents its primary physiological role.
Biological Context
Subcellular Location: Secreted
Disease Association: Combined saposin deficiency (PSAPD) : An autosomal recessive storage disorder characterized by hepatosplenomegaly and severe neurologic disease, due to absence of all saposins. PSAPD has a fatal outcome in infancy. [The disease is caused by variants affecting the gene represented in this entry] | Metachromatic leukodystrophy due to saposin B deficiency (MLDSAPB) : A form of metachromatic leukodystrophy biochemically characterized by tissue accumulation of cerebroside-3-sulfate, saposin B deficiency, and normal arylsulfatase A activity. Clinical manifestations include periventricular white matter abnormalities, demyelination, and peripheral neuropathy. Additional neurological features include dysarthria, ataxic gait, psychomotor regression, seizures, cognitive decline and spastic quadriparesis. [The disease is caused by variants affecting the gene represented in this entry] | Gaucher disease, atypical, due to saposin C deficiency (GDSAPC) : A disease characterized by marked glucosylceramide accumulation in the spleen without having a deficiency of glucosylceramide-beta glucosidase characteristic of classic Gaucher disease. Gaucher disease is a lysosomal storage disorder characterized by skeletal deterioration, hepatosplenomegaly, and organ dysfunction. There are several subtypes based on the presence and severity of neurological involvement. [The disease is caused by variants affecting the gene represented in this entry] | Krabbe disease, atypical, due to saposin A deficiency (KRBSAPA) : An autosomal recessive disorder of galactosylceramide metabolism. Clinical features include neurologic regression around age 3 months, loss of spontaneous movements, hyporeflexia, generalized brain atrophy, and diffuse white matter dysmyelination. [The disease is caused by variants affecting the gene represented in this entry] | [Defects in PSAP saposin-D region are found in a variant of Tay-Sachs disease (GM2-gangliosidosis)] | Parkinson disease 24, autosomal dominant (PARK24) : An autosomal dominant form of Parkinson disease, a complex neurodegenerative disorder characterized by bradykinesia, resting tremor, muscular rigidity and postural instability, as well as by a clinically significant response to treatment with levodopa. The pathology involves the loss of dopaminergic neurons in the substantia nigra and the presence of Lewy bodies (intraneuronal accumulations of aggregated proteins), in surviving neurons in various areas of the brain. PARK24 shows incomplete penetrance. [Disease susceptibility is associated with variants affecting the gene represented in this entry]
Product Specifications
Recombinant Human Prosaposin (PSAP), partial is a recombinant protein from Homo sapiens (Human), expressed in Yeast, covering amino acids 311-391aa, with N-terminal 6xHis-tagged tag, molecular weight 11.1kDa, purity Greater than 90% as determined by SDS-PAGE.. Suitable for ELISA and Western Blot applications.
