Go Annotations as Summary Text (Tabular View) (GO Graph)

GO curators for mouse genes have assigned the following annotations to the gene product of Hexa. (This text reflects annotations as of Wednesday, January 23, 2013.) MGI curation of this mouse gene is considered complete, including annotations derived from the biomedical literature as of July 20, 2005. If you know of any additional information regarding this mouse gene please let us know. Please supply mouse gene symbol and a PubMed ID.

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Summary from NCBI RefSeq

[Summary is not available for the mouse gene. This summary is for the human ortholog.] This gene encodes the alpha subunit of the lysosomal enzyme beta-hexosaminidase that, together with the cofactor GM2 activator protein, catalyzes the degradation of the ganglioside GM2, and other molecules containing terminal N-acetyl hexosamines. Beta-hexosaminidase is composed of two subunits, alpha and beta, which are encoded by separate genes. Both beta-hexosaminidase alpha and beta subunits are members of family 20 of glycosyl hydrolases. Mutations in the alpha or beta subunit genes lead to an accumulation of GM2 ganglioside in neurons and neurodegenerative disorders termed the GM2 gangliosidoses. Alpha subunit gene mutations lead to Tay-Sachs disease (GM2-gangliosidosis type I). [provided by RefSeq, Jul 2009]

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Summary text based on GO annotations supported by experimental evidence in mouse

• Researchers have inferred from direct assay, that the gene product of Hexa
  • participates in the following biological processes:
    • metabolic process ^{[2, 5, 15, 16]}
  • performs the following molecular functions:
    • beta-N-acetylhexosaminidase activity ^{[2, 5, 15, 16]}
  • is located in the following cellular components:
    • lysosome ^{[5, 13]}
    • membrane ^[5]
• Researchers have inferred, based on phenotypic analysis of mouse mutants, that the gene product of Hexa
  • participates in the following biological processes:
    • adult walking behavior ^[8]
    • cell morphogenesis involved in neuron differentiation ^[8]
    • ganglioside catabolic process ^{[7, 9, 13, 14]}
    • lipid storage ^{[6, 7, 8]}
    • lysosome organization ^{[1, 2, 4, 8, 10, 13, 14]}
    • neuromuscular process controlling posture ^[8]
    • sexual reproduction ^[13]
  • performs the following molecular functions:
    • beta-N-acetylhexosaminidase activity ^{[2, 3, 9, 14]}
• Researchers have inferred, based on genetic interactions, that the gene product of Hexa
  • participates in the following biological processes:
    • glycosaminoglycan metabolic process based on interactions with Hexb ^[11]
    • locomotory behavior based on interactions with Hexb ^[11]
    • lysosome organization based on interactions with Hexb ^{[11, 12]}
    • myelination based on interactions with Hexb ^[12]
    • neuromuscular process controlling balance based on interactions with Hexb ^[11]
    • sensory perception of sound based on interactions with Hexb ^[11]
    • skeletal system development based on interactions with Hexb ^{[11, 12]}
  • performs the following molecular functions:
    • beta-N-acetylhexosaminidase activity based on interactions with Hexb ^[11]

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Summary text based on GO annotations supported by experimental evidence in other organisms

• From comparative sequence analysis (see table for details), MGI curators have determined that the gene product of Hexa:
  • performs the following molecular functions:
    • protein heterodimerization activity

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Summary text based on GO annotations supported by structural data

• Hexa encodes a protein or proteins that contain the following InterPro domains: Beta-hexosaminidase subunit alpha/beta, Glycoside hydrolase family 20, catalytic core, Glycoside hydrolase, catalytic domain, Glycoside hydrolase, superfamily, Glycosyl hydrolase family 20, domain 2, indicating that the gene product:
  • participates in the following biological processes:
    • carbohydrate metabolic process
  • performs the following molecular functions:
    • catalytic activity
    • cation binding
    • hydrolase activity, hydrolyzing O-glycosyl compounds

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Summary text for additional MGI annotations

• Automated translation to GO terms of SwissProt keywords that describe Hexa indicates that it:
  • performs the following molecular functions:
    • hydrolase activity
    • hydrolase activity, acting on glycosyl bonds

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References

1. Adamali HI et al. (1999) II. Characterization and development of the regional- and cellular-specific abnormalities in the epididymis of mice with beta-hexosaminidase A deficiency. J Androl, 20:803-24. (PubMed:10591619)
2. Cohen-Tannoudji M et al. (1995) Disruption of murine Hexa gene leads to enzymatic deficiency and to neuronal lysosomal storage, similar to that observed in Tay-Sachs disease. Mamm Genome, 6:844-9. (PubMed:8747922)
3. Guidotti JE et al. (1999) Adenoviral gene therapy of the Tay-Sachs disease in hexosaminidase A-deficient knock-out mice. Hum Mol Genet, 8:831-8. (PubMed:10196372)
4. Huang JQ et al. (1997) Apoptotic cell death in mouse models of GM2 gangliosidosis and observations on human Tay-Sachs and Sandhoff diseases. Hum Mol Genet, 6:1879-85. (PubMed:9302266)
5. Lankar D et al. (2002) Dynamics of major histocompatibility complex class II compartments during B cell receptor-mediated cell activation. J Exp Med, 195:461-72. (PubMed:11854359)
6. Liu Y et al. (1999) A genetic model of substrate deprivation therapy for a glycosphingolipid storage disorder [see comments] J Clin Invest, 103:497-505. (PubMed:10021458)
7. Liu Y et al. (1997) Mouse model of GM2 activator deficiency manifests cerebellar pathology and motor impairment. Proc Natl Acad Sci U S A, 94:8138-43. (PubMed:9223328)
8. Miklyaeva EI et al. (2004) Late onset Tay-Sachs disease in mice with targeted disruption of the Hexa gene: behavioral changes and pathology of the central nervous system. Brain Res, 1001:37-50. (PubMed:14972652)
9. Phaneuf D et al. (1996) Dramatically different phenotypes in mouse models of human Tay-Sachs and Sandhoff diseases. Hum Mol Genet, 5:1-14. (PubMed:8789434)
10. Platt FM et al. (1997) Prevention of lysosomal storage in Tay-Sachs mice treated with N-butyldeoxynojirimycin. Science, 276:428-31. (PubMed:9103204)
11. Sango K et al. (1996) Mice lacking both subunits of lysosomal beta-hexosaminidase display gangliosidosis and mucopolysaccharidosis. Nat Genet, 14:348-52. (PubMed:8896570)
12. Suzuki K et al. (1997) Mice deficient in all forms of lysosomal beta-hexosaminidase show mucopolysaccharidosis-like pathology. J Neuropathol Exp Neurol, 56:693-703. (PubMed:9184660)
13. Trasler J et al. (1998) Characterization of the testis and epididymis in mouse models of human Tay Sachs and Sandhoff diseases and partial determination of accumulated gangliosides. Endocrinology, 139:3280-8. (PubMed:9645704)
14. Yamanaka S et al. (1994) Targeted disruption of the Hexa gene results in mice with biochemical and pathologic features of Tay-Sachs disease. Proc Natl Acad Sci U S A, 91:9975-9. (PubMed:7937929)
15. Yasue M et al. (1991) Chromosomal assignments of 23 biochemical loci of the rat by using rat x mouse somatic cell hybrids. Cytogenet Cell Genet, 57:142-8. (PubMed:1914521)
16. Yuziuk JA et al. (1998) Specificity of mouse GM2 activator protein and beta-N-acetylhexosaminidases A and B. Similarities and differences with their human counterparts in the catabolism of GM2. J Biol Chem, 273:66-72. (PubMed:9417048)

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Gene Ontology Evidence Code Abbreviations:

EXP Inferred from experiment

IC Inferred by curator

IDA Inferred from direct assay

IEA Inferred from electronic annotation

IGI Inferred from genetic interaction

IMP Inferred from mutant phenotype

IPI Inferred from physical interaction

ISS Inferred from sequence or structural similarity

ISO Inferred from sequence orthology

ISA Inferred from sequence alignment

ISM Inferred from sequence model

NAS Non-traceable author statement

ND No biological data available

RCA Reviewed computational analysis

TAS Traceable author statement

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