ID:HEXA_HUMAN DESCRIPTION: RecName: Full=Beta-hexosaminidase subunit alpha; EC=3.2.1.52; AltName: Full=Beta-N-acetylhexosaminidase subunit alpha; Short=Hexosaminidase subunit A; AltName: Full=N-acetyl-beta-glucosaminidase subunit alpha; Flags: Precursor; FUNCTION: Responsible for the degradation of GM2 gangliosides, and a variety of other molecules containing terminal N-acetyl hexosamines, in the brain and other tissues. The form B is active against certain oligosaccharides. The form S has no measurable activity. CATALYTIC ACTIVITY: Hydrolysis of terminal non-reducing N-acetyl- D-hexosamine residues in N-acetyl-beta-D-hexosaminides. SUBUNIT: There are 3 forms of beta-hexosaminidase: hexosaminidase A is a trimer composed of one subunit alpha, one subunit beta chain A and one subunit beta chain B; hexosaminidase B is a tetramer of two subunit beta chains A and two subunit beta chains B; hexosaminidase S is a homodimer of two alpha subunits. The two beta chains are derived from the cleavage of the beta subunit. INTERACTION: P00519:ABL1; NbExp=1; IntAct=EBI-723519, EBI-375543; P46108:CRK; NbExp=1; IntAct=EBI-723519, EBI-886; P06241:FYN; NbExp=1; IntAct=EBI-723519, EBI-515315; SUBCELLULAR LOCATION: Lysosome. PTM: N-linked glycan at Asn-115 consists of Man(3)-GlcNAc(2). DISEASE: Defects in HEXA are the cause of GM2-gangliosidosis type 1 (GM2G1) [MIM:272800]; also known as Tay-Sachs disease. GM2- gangliosidosis is an autosomal recessive lysosomal storage disease marked by the accumulation of GM2 gangliosides in the neuronal cells. GM2G1 is characterized by GM2 gangliosides accumulation in the absence of HEXA activity, leading to neurodegeneration and, in the infantile form, death in early childhood. GM2G1 has an increased incidence among Ashkenazi Jews and French Canadians in eastern Quebec. It exists in several forms: infantile (most common and most severe), juvenile and adult (late onset). SIMILARITY: Belongs to the glycosyl hydrolase 20 family. WEB RESOURCE: Name=HEXAdb; Note=HEXA mutation database; URL="http://www.hexdb.mcgill.ca/?Topic=HEXAdb"; WEB RESOURCE: Name=GeneReviews; URL="http://www.ncbi.nlm.nih.gov/sites/GeneTests/lab/gene/HEXA";
ModBase Predicted Comparative 3D Structure on P06865
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Other Names for This Gene
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Methods, Credits, and Use Restrictions
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