Overview
| Uniprot ID | P17900 |
|---|
| Protein Name | Ganglioside GM2 activator |
|---|
| Gene Name | GM2A |
|---|
| Organism | Homo sapiens |
|---|
Kla Sites from experimental identification
| Position |
Flanking peptide |
| 179 |
SVLSSSGKRLGCIKI |
Function
Lipid-binding and transfer protein essential for lysosomal degradation of ganglioside GM2. Extracts single GM2 molecules from intralysosomal luminal vesicle (ILV) membranes and presents them in soluble form to beta-hexosaminidase A (HEXA) for cleavage of N-acetyl-D-galactosamine and conversion to GM3 (PubMed:30988135, PubMed:8900233). Forms a stoichiometric GM2-GM2A complex that serves as the substrate for HEXA (PubMed:30988135, PubMed:8900233). Also stimulates the breakdown of glycolipid GA2 by HEXA (By similarity). Possesses dual function: membrane lipid mobilization/solubilization and lipid substrate presentation to hydrolases (PubMed:30988135). The large binding pocket can accommodate several single-chain phospholipids and fatty acids (By similarity). Exhibits some calcium-independent phospholipase activity (By similarity). Participates in cholesterol transfer (PubMed:17552909)
Protein Sequence
10
MQSLMQAPLL
20
IALGLLLAAP
30
AQAHLKKPSQ
40
LSSFSWDNCD
50
EGKDPAVIRS
60
LTLEPDPIIV
70
PGNVTLSVMG
80
STSVPLSSPL
90
KVDLVLEKEV
100
AGLWIKIPCT
110
DYIGSCTFEH
120
FCDVLDMLIP
130
TGEPCPEPLR
140
TYGLPCHCPF
150
KEGTYSLPKS
160
EFVVPDLELP
170
SWLTTGNYRI
180
ESVLSSSGKR
190
LGCIKIAASL
KGI
Gene Ontology
| Classification |
GO ID |
Description |
| Cellular Component |
GO:0016324 |
apical plasma membrane |
| Cellular Component |
GO:0035578 |
azurophil granule lumen |
| Cellular Component |
GO:0016323 |
basolateral plasma membrane |
| Cellular Component |
GO:0009898 |
cytoplasmic side of plasma membrane |
| Cellular Component |
GO:0070062 |
extracellular exosome |
| Cellular Component |
GO:0005576 |
extracellular region |
| Cellular Component |
GO:0043202 |
lysosomal lumen |
| Molecular Function |
GO:0032428 |
beta-N-acetylgalactosaminidase activity |
| Molecular Function |
GO:0005319 |
lipid transporter activity |
| Molecular Function |
GO:0016004 |
phospholipase activator activity |
| Molecular Function |
GO:0030290 |
sphingolipid activator protein activity |
| Biological Process |
GO:0006689 |
ganglioside catabolic process |
| Biological Process |
GO:0046479 |
glycosphingolipid catabolic process |
| Biological Process |
GO:0006869 |
lipid transport |
Reference
[1] Yang Z, Yan C, Ma J, Peng P, Ren X et al.. Lactylome analysis suggests lactylation-dependent mechanisms of metabolic adaptation in hepatocellular carcinoma.. Nat Metab 5(1):61-79. 2023 Jan. PMID: 36593272.