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Details on Person UniProt:P07602-1 PSAP

Class:IdReferenceIsoform:402541
_chainChangeLogsignal peptide:1-16 added on Fri February 6 2015;chain:17-524 added on Fri February 6 2015;propeptide:17-58 added on Fri February 6 2015;chain:60-142 added on Fri February 6 2015;propeptide:144-194 added on Fri February 6 2015;chain:195-274 added on Fri February 6 2015;chain:195-273 added on Fri February 6 2015;propeptide:276-309 added on Fri February 6 2015;chain:311-391 added on Fri February 6 2015;propeptide:393-403 added on Fri February 6 2015;chain:405-486 added on Fri February 6 2015;propeptide:488-524 added on Fri February 6 2015;propeptide:17-58 removed on Fri February 12 2016;propeptide:144-194 removed on Fri February 12 2016;propeptide:276-309 removed on Fri February 12 2016;chain:311-391 removed on Fri February 12 2016;propeptide:393-403 removed on Fri February 12 2016;propeptide:488-524 removed on Fri February 12 2016;propeptide:17-59 added on Fri February 12 2016;propeptide:143-194 added on Fri February 12 2016;propeptide:275-310 added on Fri February 12 2016;chain:311-390 added on Fri February 12 2016;propeptide:393-404 added on Fri February 12 2016;propeptide:487-524 added on Fri February 12 2016
_displayNameUniProt:P07602-1 PSAP
_timestamp2024-11-03 20:11:59
chainsignal peptide:1-16
chain:17-524
propeptide:17-59
chain:60-142
propeptide:143-194
chain:195-274
chain:195-273
propeptide:275-310
chain:311-390
propeptide:393-404
chain:405-486
propeptide:487-524
checksum71977F7A8C9E1533
commentFUNCTION Saposin-A and saposin-C stimulate the hydrolysis of glucosylceramide by beta-glucosylceramidase (EC 3.2.1.45) and galactosylceramide by beta-galactosylceramidase (EC 3.2.1.46). Saposin-C apparently acts by combining with the enzyme and acidic lipid to form an activated complex, rather than by solubilizing the substrate.FUNCTION Saposin-B stimulates the hydrolysis of galacto-cerebroside sulfate by arylsulfatase A (EC 3.1.6.8), GM1 gangliosides by beta-galactosidase (EC 3.2.1.23) and globotriaosylceramide by alpha-galactosidase A (EC 3.2.1.22). Saposin-B forms a solubilizing complex with the substrates of the sphingolipid hydrolases.FUNCTION Saposin-D is a specific sphingomyelin phosphodiesterase activator (EC 3.1.4.12).FUNCTION Behaves as a myelinotrophic and neurotrophic factor, these effects are mediated by its G-protein-coupled receptors, GPR37 and GPR37L1, undergoing ligand-mediated internalization followed by ERK phosphorylation signaling.FUNCTION Saposins are specific low-molecular mass non-enzymic proteins, they participate in the lysosomal degradation of sphingolipids, which takes place by the sequential action of specific hydrolases.SUBUNIT Saposin-B is a homodimer. Prosaposin exists as a roughly half-half mixture of monomers and disulfide-linked dimers (PubMed:10406958, PubMed:12510003, PubMed:21835174, PubMed:7730378). Monomeric prosaposin interacts (via C-terminus) with sortilin/SORT1, the interaction is required for targeting to lysosomes (PubMed:14657016, PubMed:22431521). Interacts with GRN; facilitates lysosomal delivery of progranulin from the extracellular space and the biosynthetic pathway (PubMed:26370502).INTERACTION Secreted as a fully glycosylated 70 kDa protein composed of complex glycans.ALTERNATIVE PRODUCTS Additional isoforms seem to exist.PTM The lysosomal precursor is proteolytically processed to 4 small peptides, which are similar to each other and are sphingolipid hydrolase activator proteins.PTM N-linked glycans show a high degree of microheterogeneity.PTM The one residue extended Saposin-B-Val is only found in 5% of the chains.DISEASE The disease is caused by variants affecting the gene represented in this entry.DISEASE The disease is caused by variants affecting the gene represented in this entry.DISEASE The disease is caused by variants affecting the gene represented in this entry.DISEASE The disease is caused by variants affecting the gene represented in this entry.DISEASE Defects in PSAP saposin-D region are found in a variant of Tay-Sachs disease (GM2-gangliosidosis).DISEASE Disease susceptibility is associated with variants affecting the gene represented in this entry.MISCELLANEOUS Saposin-B co-purifies with 1 molecule of phosphatidylethanolamine.
created[InstanceEdit:400710] Schmidt, EE, 2009-03-25 05:33:35
descriptionrecommendedName: Prosaposin alternativeName: Proactivator polypeptide component recommendedName: Saposin-A alternativeName: Protein A /component component recommendedName: Saposin-B-Val /component component recommendedName: Saposin-B alternativeName: Cerebroside sulfate activator shortName: CSAct alternativeName: Dispersin alternativeName: Sphingolipid activator protein 1 shortName: SAP-1 alternativeName: Sulfatide/GM1 activator /component component recommendedName: Saposin-C alternativeName: A1 activator alternativeName: Co-beta-glucosidase alternativeName: Glucosylceramidase activator alternativeName: Sphingolipid activator protein 2 shortName: SAP-2 /component component recommendedName: Saposin-D alternativeName: Component C alternativeName: Protein C /component
geneNamePSAP
GLBA
SAP1
identifierP07602
isoformParent
isSequenceChangedFALSE
keyword3D-structure
Alternative splicing
Direct protein sequencing
Disease variant
Disulfide bond
Gangliosidosis
Gaucher disease
Glycoprotein
Leukodystrophy
Lipid metabolism
Lysosome
Metachromatic leukodystrophy
Neurodegeneration
Parkinson disease
Parkinsonism
Proteomics identification
Reference proteome
Repeat
Secreted
Signal
Sphingolipid metabolism
modified[InstanceEdit:9836292] Weiser, Joel, 2023-05-25
[InstanceEdit:9852000] Weiser, Joel, 2023-11-03
[InstanceEdit:9917590] Weiser, Joel, 2024-08-09
[InstanceEdit:9926675] Weiser, Joel, 2024-11-03
namePSAP
referenceDatabase[ReferenceDatabase:2] UniProt
referenceGene[ReferenceDNASequence:8958531] ENSEMBL:ENSG00000197746 PSAP [Homo sapiens]
secondaryIdentifierSAP_HUMAN
P07292
P15793
P78538
P78541
P78546
P78547
P78558
Q53Y86
Q6IBQ6
Q92739
Q92740
Q92741
Q92742
sequenceLength524
species[Species:48887] Homo sapiens
variantIdentifierP07602-1
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