UniProt Accession

 SAP_HUMAN; P07602; P07292; P15793; P78538; P78541; P78546; P78547; P78558; Q53Y86; Q6IBQ6; Q92739; Q92740; Q92741; Q92742 

Genbank Protein ID

 J03077; D00422; BT006849; CR456746; AL731541; AC073370; CH471083; BC001503; BC004275; BC007612; M86181; X57107; X57108; M12710; J03015; M32221; M60257; M60258; M60255 

Genbank Nucleotide ID

 AAA52560.1; BAA00321.1; AAP35495.1; CAG33027.1; CAI40837.1; CAI40837.1; EAW54437.1; AAH01503.1; AAH04275.1; AAH07612.1; CAA40391.1; CAA40392.1; AAB59494.1; AAA60303.1; AAA36595.1; AAA36596.1; AAA36594.1 

Protein Name

 Proactivator polypeptide 

Protein Synonyms/Alias

 Saposin-A; Protein A; Saposin-B-Val; Saposin-B; Cerebroside sulfate activator; CSAct; Dispersin; Sphingolipid activator protein 1; SAP-1; Sulfatide/GM1 activator; Saposin-C; A1 activator; Co-beta-glucosidase; Glucosylceramidase activator; Sphingolipid activator protein 2; SAP-2; Saposin-D; Component C; Protein C 

Gene Name

 PSAP 

Gene Synonyms/Alias

 GLBA; SAP1 

Created Date

 July 27, 2013 

Organism

 Homo sapiens (Human) 

NCBI Taxa ID

 9606 

Lysine Modification

Position	Peptide	Type	References
303	LELVEPIKKHEVPAK	ubiquitination	[1]

Reference

 [1] Systematic and quantitative assessment of the ubiquitin-modified proteome.
 Kim W, Bennett EJ, Huttlin EL, Guo A, Li J, Possemato A, Sowa ME, Rad R, Rush J, Comb MJ, Harper JW, Gygi SP.
 Mol Cell. 2011 Oct 21;44(2):325-40. [PMID: 21906983] 

Functional Description

 The lysosomal degradation of sphingolipids takes place by the sequential action of specific hydrolases. Some of these enzymes require specific low-molecular mass, non-enzymic proteins: the sphingolipids activator proteins (coproteins). 

Sequence Annotation

 DOMAIN 18 58 Saposin A-type 1.
 DOMAIN 59 142 Saposin B-type 1.
 DOMAIN 194 275 Saposin B-type 2.
 DOMAIN 311 392 Saposin B-type 3.
 DOMAIN 405 486 Saposin B-type 4.
 DOMAIN 488 524 Saposin A-type 2.
 CARBOHYD 80 80 N-linked (GlcNAc...).
 CARBOHYD 101 101 N-linked (GlcNAc...).
 CARBOHYD 215 215 N-linked (GlcNAc...) (complex).
 CARBOHYD 332 332 N-linked (GlcNAc...).
 CARBOHYD 426 426 N-linked (GlcNAc...).
 DISULFID 63 138
 DISULFID 66 132
 DISULFID 94 106
 DISULFID 198 271
 DISULFID 201 265
 DISULFID 230 241
 DISULFID 315 388
 DISULFID 318 382
 DISULFID 346 357
 DISULFID 409 482
 DISULFID 412 476
 DISULFID 440 451  

Keyword

 3D-structure; Alternative splicing; Complete proteome; Direct protein sequencing; Disease mutation; Disulfide bond; Gangliosidosis; Gaucher disease; Glycoprotein; Leukodystrophy; Lipid metabolism; Lysosome; Metachromatic leukodystrophy; Reference proteome; Repeat; Signal; Sphingolipid metabolism. 

Sequence Source

 UniProt (SWISSPROT/TrEMBL); GenBank; EMBL 

Protein Length

 524 AA 

Protein Sequence

Gene Ontology

 GO:0005615; C:extracellular space; IDA:BHF-UCL.
 GO:0005794; C:Golgi apparatus; IDA:HPA.
 GO:0016021; C:integral to membrane; TAS:ProtInc.
 GO:0043202; C:lysosomal lumen; TAS:Reactome.
 GO:0005765; C:lysosomal membrane; TAS:Reactome.
 GO:0005739; C:mitochondrion; IEA:Compara.
 GO:0008047; F:enzyme activator activity; TAS:ProtInc.
 GO:0008289; F:lipid binding; TAS:ProtInc.
 GO:0071310; P:cellular response to organic substance; IEA:Compara.
 GO:0060742; P:epithelial cell differentiation involved in prostate gland development; IEA:Compara.
 GO:0006687; P:glycosphingolipid metabolic process; TAS:Reactome.
 GO:0006869; P:lipid transport; TAS:ProtInc.
 GO:0030168; P:platelet activation; TAS:Reactome.
 GO:0002576; P:platelet degranulation; TAS:Reactome.
 GO:0060736; P:prostate gland growth; IEA:Compara.
 GO:0019216; P:regulation of lipid metabolic process; IEA:Compara.
 GO:0043408; P:regulation of MAPK cascade; IEA:Compara.
 GO:0044281; P:small molecule metabolic process; TAS:Reactome. 

Interpro

 IPR003119; SapA.
 IPR007856; SapB_1.
 IPR008138; SapB_2.
 IPR008373; Saposin.
 IPR011001; Saposin-like.
 IPR021165; Saposin_chordata.
 IPR008139; SaposinB. 

Pfam

 PF02199; SapA
 PF05184; SapB_1
 PF03489; SapB_2 

SMART

 SM00162; SAPA
 SM00741; SapB 

PROSITE

 PS51110; SAP_A
 PS50015; SAP_B 

PRINTS

 PR01797; SAPOSIN.