Q60648 (SAP3_MOUSE) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names

Recommended name:
Ganglioside GM2 activator

Alternative name(s):
Cerebroside sulfate activator protein
GM2-AP
Shingolipid activator protein 3
Short name=SAP-3

Gene names

Name:

Gm2a

Organism

Mus musculus (Mouse) [Reference proteome]

Taxonomic identifier

10090 [NCBI]

Taxonomic lineage

cellular organisms › Eukaryota › Opisthokonta › Metazoa › Eumetazoa › Bilateria › Deuterostomia › Chordata › Craniata › Vertebrata › Gnathostomata › Teleostomi › Euteleostomi › Sarcopterygii › Tetrapoda › Amniota › Mammalia › Theria › Eutheria › Euarchontoglires › Glires › Rodentia › Sciurognathi › Muroidea › Muridae › Murinae › Mus › Mus

Protein attributes

Sequence length	193 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is further processed into a mature form.
Protein existence	Evidence at protein level

General annotation (Comments)

Function	Binds gangliosides and stimulates ganglioside GM2 degradation. It stimulates only the breakdown of ganglioside GM2 and glycolipid GA2 by beta-hexosaminidase A. It extracts single GM2 molecules from membranes and presents them in soluble form to beta-hexosaminidase A for cleavage of N-acetyl-D-galactosamine and conversion to GM3. The large binding pocket can accommodate several single chain phospholipids and fatty acids, GM2A also exhibits some calcium-independent phospholipase activity. Ref.5
Subcellular location	Lysosome.
Tissue specificity	Widely expressed. Most abundant in kidney and testis.

Ontologies

Keywords
Biological process	Lipid metabolism Sphingolipid metabolism
Cellular component	Lysosome
Domain	Signal
Molecular function	Hydrolase
PTM	Disulfide bond Glycoprotein
Technical term	3D-structure Complete proteome Reference proteome
Gene Ontology (GO)
Biological_process	ganglioside catabolic process Inferred from mutant phenotype PubMed 9223328. Source: MGI learning or memory Inferred from mutant phenotype PubMed 9223328. Source: MGI lipid storage Inferred from mutant phenotype PubMed 9223328. Source: MGI neuromuscular process controlling balance Inferred from mutant phenotype PubMed 9223328. Source: MGI oligosaccharide catabolic process Inferred from mutant phenotype PubMed 9584189. Source: MGI
Cellular_component	lysosome Inferred from electronic annotation. Source: UniProtKB-SubCell mitochondrion Inferred from direct assay PubMed 14651853. Source: MGI nucleolus Inferred from electronic annotation. Source: Compara
Molecular_function	beta-N-acetylhexosaminidase activity Inferred from mutant phenotype PubMed 9584189. Source: MGI enzyme activator activity Inferred from direct assay PubMed 7980537. Source: MGI
Complete GO annotation...

Sequence annotation (Features)

Feature key

Position(s)

Length

Description

Graphical view

Feature identifier

Molecule processing

Signal peptide

1 – 20

20

Potential

Chain

21 – 193

173

Ganglioside GM2 activator

PRO_0000031643

Amino acid modifications

Glycosylation

151

1

N-linked (GlcNAc...) Potential

Disulfide bond

39 ↔ 183

Ref.5

Disulfide bond

99 ↔ 106

Ref.5

Disulfide bond

112 ↔ 138

Ref.5

Disulfide bond

125 ↔ 136

Ref.5

Experimental info

Mutagenesis

168

1

Y → S: Abolishes phospholipid binding. Ref.5

Sequence conflict

53

1

I → T in AAA21543. Ref.1

Secondary structure

1

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193

Helix Strand Turn

Details...

Beta strand

35 – 39

5

Helix

40 – 42

3

Beta strand

44 – 58

15

Beta strand

60 – 74

15

Beta strand

81 – 90

10

Beta strand

93 – 96

4

Beta strand

107 – 109

3

Helix

111 – 118

8

Turn

127 – 133

7

Beta strand

142 – 153

12

Beta strand

165 – 176

12

Beta strand

179 – 190

12

Sequences

	Sequence		Length	Mass (Da)
	Q60648 [UniParc]. Last modified November 1, 1997. Version 2. Checksum: 59CC4ABE56FA1FC7	FASTA	193	20,824
	10 20 30 40 50 60 MHRLPLLLLL GLLLAGSVAP ARLVPKRLSQ LGGFSWDNCD EGKDPAVIKS LTIQPDPIVV 70 80 90 100 110 120 PGDVVVSLEG KTSVPLTAPQ KVELTVEKEV AGFWVKIPCV EQLGSCSYEN ICDLIDEYIP 130 140 150 160 170 180 PGESCPEPLH TYGLPCHCPF KEGTYSLPTS NFTVPDLELP SWLSTGNYRI QSILSSGGKR 190 LGCIKIAASL KGR

References

	« Hide 'large scale' referencesShow 'large scale' references »
[1]	"The mouse gene encoding the GM2 activator protein (Gm2a): cDNA sequence, expression, and chromosome mapping." Yamanaka S., Johnson O.N., Lyu M.S., Kozak C.A., Proia R.L. Genomics 24:601-604(1994) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE. Strain: C57BL/6 X CBA. Tissue: Liver.
[2]	"Cloning and sequence analysis of a cDNA clone coding for the mouse GM2 activator protein." Bellachioma G., Stirling J.L., Orlacchio A., Beccari T. Biochem. J. 294:227-230(1993) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA].
[3]	"Structural organization and expression of the gene for the mouse GM2 activator protein." Bertoni C., Appolloni M.G., Stirling J.L., Li S.C., Li Y.T., Orlacchio A., Beccari T. Mamm. Genome 8:90-93(1997) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA]. Strain: C57BL/6 X CBA.
[4]	"The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC)." The MGC Project Team Genome Res. 14:2121-2127(2004) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA]. Strain: C57BL/6J. Tissue: Mammary gland.
[5]	"Crystal structure analysis of phosphatidylcholine-GM2-activator product complexes: evidence for hydrolase activity." Wright C.S., Mi L.Z., Lee S., Rastinejad F. Biochemistry 44:13510-13521(2005) [PubMed] [Europe PMC] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (2.5 ANGSTROMS) OF 32-193 IN COMPLEX WITH LYSOPHOSPHATIDYLCHOLINE, FUNCTION, DISULFIDE BONDS, MUTAGENESIS OF TYR-168.
+	Additional computationally mapped references.

Cross-references

Sequence databases

EMBL
GenBank
DDBJ

U09816 mRNA. Translation: AAA21543.1.
L19526 mRNA. Translation: AAA61929.1.
U34359 , U34356, U34357, U34358 Genomic DNA. Translation: AAB06275.1. Sequence problems.
BC004651 mRNA. Translation: AAH04651.1.

IPI

IPI00119095.

PIR

S35613.

RefSeq

NP_034429.1. NM_010299.3.

UniGene

Mm.287807.

3D structure databases

PDBe
RCSB PDB
PDBj

Entry	Method	Resolution (Å)	Chain	Positions	PDBsum
2AGC	X-ray	2.50	A	32-193	[»]

ProteinModelPortal

Q60648.

SMR

Q60648. Positions 32-193.

ModBase

Search...

Proteomic databases

PaxDb

Q60648.

PRIDE

Q60648.

Protocols and materials databases

StructuralBiologyKnowledgebase

Search...

Genome annotation databases

Ensembl

ENSMUST00000000608; ENSMUSP00000000608; ENSMUSG00000000594.

GeneID

14667.

KEGG

mmu:14667.

Organism-specific databases

CTD

2760.

MGI

MGI:95762. Gm2a.

Phylogenomic databases

eggNOG

NOG47814.

GeneTree

ENSGT00390000003288.

HOGENOM

HOG000031350.

HOVERGEN

HBG000260.

InParanoid

Q60648.

KO

K12383.

OMA

PFKEGTY.

OrthoDB

EOG48PMMH.

Gene expression databases

ArrayExpress

Q60648.

Bgee

Q60648.

CleanEx

MM_GM2A.

Genevestigator

Q60648.

GermOnline

ENSMUSG00000000594. Mus musculus.

Family and domain databases

ProtoNet

Search...

Other

EvolutionaryTrace

Q60648.

NextBio

286546.

SOURCE

Search...

Entry information

Entry name

SAP3_MOUSE

Accession

Primary (citable) accession number: Q60648
Secondary accession number(s): Q61610, Q61819

Entry history

Integrated into UniProtKB/Swiss-Prot:	November 1, 1997
Last sequence update:	November 1, 1997
Last modified:	April 3, 2013
This is version 95 of the entry and version 2 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Chordata Protein Annotation Program