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HEXA - hexosaminidase subunit alpha (human)

Gene
Symbol
Dates
  • Create:
    2016-09-14
  • Modify:
    2025-01-29
Description
This gene encodes a member of the glycosyl hydrolase 20 family of proteins. The encoded preproprotein is proteolytically processed to generate the alpha subunit of the lysosomal enzyme beta-hexosaminidase. This enzyme, together with the cofactor GM2 activator protein, catalyzes the degradation of the ganglioside GM2, and other molecules containing terminal N-acetyl hexosamines. Mutations in this gene lead to an accumulation of GM2 ganglioside in neurons, the underlying cause of neurodegenerative disorders termed the GM2 gangliosidoses, including Tay-Sachs disease (GM2-gangliosidosis type I). Alternative splicing results in multiple transcript variants, at least one of which encodes a preproprotein that is proteolytically processed. [provided by RefSeq, Jan 2016]
Enables acetylglucosaminyltransferase activity; beta-N-acetylhexosaminidase activity; and protein heterodimerization activity. Involved in ganglioside catabolic process and glycosaminoglycan biosynthetic process. Located in azurophil granule and cytosol. Part of beta-N-acetylhexosaminidase complex. Implicated in Tay-Sachs disease.

The HEXA gene provides instructions for making one part (subunit) of an enzyme called beta-hexosaminidase A. Specifically, the protein produced from the HEXA gene forms the alpha subunit of this enzyme. One alpha subunit joins with one beta subunit (produced from the HEXB gene) to form a functioning enzyme.

Beta-hexosaminidase A plays a critical role in the brain and spinal cord (central nervous system). This enzyme is found in lysosomes, which are structures in cells that break down toxic substances and act as recycling centers. Within lysosomes, beta-hexosaminidase A forms part of a complex that breaks down a fatty substance called GM2 ganglioside.

1 Names and Identifiers

1.1 Synonyms

  • TSD
  • beta-hexosaminidase subunit alpha
  • N-acetyl-beta-glucosaminidase subunit alpha
  • beta-N-acetylhexosaminidase subunit alpha
  • hexosaminidase A (alpha polypeptide)
  • hexosaminidase subunit A

1.2 Other Identifiers

1.2.1 HGNC ID

1.2.2 Ensembl ID

1.2.3 Alliance Gene ID

1.2.4 Bgee Gene ID

1.2.5 Enzyme Commission (EC) Number

1.2.6 GenCC ID

1.2.7 GlyCosmos Gene

1.2.8 KEGG Gene

1.2.9 MIM Number

1.2.10 NCI Thesaurus Code

1.2.11 Open Targets ID

1.2.12 PharmGKB ID

1.2.13 Pharos Target

1.2.14 VEuPathDB ID

1.2.15 Wikidata

3 Proteins

3.1 Protein Function

Hydrolyzes the non-reducing end N-acetyl-D-hexosamine and/or sulfated N-acetyl-D-hexosamine of glycoconjugates, such as the oligosaccharide moieties from proteins and neutral glycolipids, or from certain mucopolysaccharides (PMID: 11707436, PMID: 8123671, PMID: 8672428, PMID: 9694901). The isozyme S is as active as the isozyme A on the anionic bis-sulfated glycans, the chondroitin-6-sulfate trisaccharide (C6S-3), and the dermatan sulfate pentasaccharide, and the sulfated glycosphingolipid SM2 (PMID: 11707436). The isozyme B does not hydrolyze each of these substrates, however hydrolyzes efficiently neutral oligosaccharide (PMID: 11707436). Only the isozyme A is responsible for the degradation of GM2 gangliosides in the presence of GM2A (PMID: 8123671, PMID: 8672428, PMID: 9694901).

3.2 Protein Isoforms

Isoform
Isoform 1
UniProt ID
RefSeq Accession
Isoform
Isoform 2
UniProt ID
RefSeq Accession

3.3 Protein 3D Structures

3.3.1 PDB Structures

3.3.2 NCBI Protein Structures

3.3.3 AlphaFold Structures

Highly accurate protein structure prediction with AlphaFold. Nature. 2021 Aug;596(7873):583-589. DOI:10.1038/s41586-021-03819-2. PMID:34265844; PMCID:PMC8371605

3.4 Protein Targets

4 Chemicals and Bioactivities

4.1 Tested Compounds

5 BioAssays

5.1 Small-Molecule BioAssays

5.2 RNAi BioAssays

6 Diseases and Phenotypes

6.1 GHR Health Conditions

6.2 KEGG Diseases

6.3 OMIM Phenotypes

6.4 MedGen Diseases

6.5 Gene-Disease Associations

Glyco-Disease Genes Database (GDGDB): https://acgg.asia/db/diseases/gdgdb

7 Interactions and Pathways

7.1 Chemical-Gene Interactions

7.2 Interactions

7.3 Pathways

8 Biochemical Reactions

9 Expression

10 Target Development Level

11 Literature

11.1 Consolidated References

11.2 Gene-Chemical Co-Occurrences in Literature

11.3 Gene-Gene Co-Occurrences in Literature

11.4 Gene-Disease Co-Occurrences in Literature

12 Patents

13 Classification

13.1 Gene Family

13.2 NCI Thesaurus Tree

13.3 Gene Ontology: Biological Process

13.4 Gene Ontology: Cellular Component

13.5 Gene Ontology: Molecular Function

13.6 ChEMBL Target Tree

13.7 Enzyme Classification

14 Information Sources

  1. NCBI Gene
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    https://www.ncbi.nlm.nih.gov/home/about/policies/
  2. PubChem
  3. Alliance of Genome Resources
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    All annotations and data produced by Alliance members that are accessible from alliancegenome.org are distributed under a CC BY 4.0 license (https://creativecommons.org/licenses/by/4.0/).
    https://www.alliancegenome.org/privacy-warranty-licensing
  4. MedlinePlus Genetics
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    https://medlineplus.gov/about/using/usingcontent/
  5. BindingDB
    LICENSE
    All data curated by BindingDB staff are provided under the Creative Commons Attribution 3.0 License (https://creativecommons.org/licenses/by/3.0/us/).
    https://www.bindingdb.org/rwd/bind/info.jsp
  6. Comparative Toxicogenomics Database (CTD)
    LICENSE
    It is to be used only for research and educational purposes. Any reproduction or use for commercial purpose is prohibited without the prior express written permission of NC State University.
    http://ctdbase.org/about/legal.jsp
  7. Drug Gene Interaction database (DGIdb)
    LICENSE
    The data used in DGIdb is all open access and where possible made available as raw data dumps in the downloads section.
    http://www.dgidb.org/downloads
  8. BioGRID
    LICENSE
    The MIT License (MIT); Copyright Mike Tyers Lab
    https://wiki.thebiogrid.org/doku.php/terms_and_conditions
  9. STRING: functional protein association networks
  10. GlyCosmos Glycoscience Portal
    LICENSE
    All copyrightable parts of the datasets in GlyCosmos are under the Creative Commons Attribution (CC BY 4.0) License.
    https://glycosmos.org/license
  11. Open Targets
    LICENSE
    Datasets generated by the Open Targets Platform are freely available for download.
    https://platform-docs.opentargets.org/licence
  12. Gene Curation Coalition (GenCC)
    LICENSE
    The GenCC data are available free of restriction under a CC0 1.0 Universal (CC0 1.0) Public Domain Dedication.
    https://thegencc.org/terms.html
    HEXA
  13. HUGO Gene Nomenclature Committee (HGNC)
    LICENSE
    No restrictions are imposed on access to, or use of, the data provided by the HGNC, which are provided to enhance knowledge and encourage progress in the scientific community.
    https://www.genenames.org/about/
  14. KEGG
    LICENSE
    Academic users may freely use the KEGG website. Non-academic use of KEGG generally requires a commercial license
    https://www.kegg.jp/kegg/legal.html
  15. NCBI Gene Expression Omnibus (GEO)
  16. NCBI MedGen
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    NCBI Website and Data Usage Policies and Disclaimers
    https://www.ncbi.nlm.nih.gov/home/about/policies/
  17. NCBI Structure
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    NCBI Website and Data Usage Policies and Disclaimers
    https://www.ncbi.nlm.nih.gov/home/about/policies/
  18. NCI Thesaurus (NCIt)
    LICENSE
    Unless otherwise indicated, all text within NCI products is free of copyright and may be reused without our permission. Credit the National Cancer Institute as the source.
    https://www.cancer.gov/policies/copyright-reuse
  19. Online Mendelian Inheritance in Man (OMIM)
    LICENSE
    The OMIM database is made available to the general public subject to certain restrictions.
    https://omim.org/help/copyright
  20. PharmGKB
    LICENSE
    PharmGKB data are subject to the Creative Commons Attribution-ShareALike 4.0 license (https://creativecommons.org/licenses/by-sa/4.0/).
    https://www.pharmgkb.org/page/policies
  21. Pharos
    LICENSE
    Data accessed from Pharos and TCRD is publicly available from the primary sources listed above. Please respect their individual licenses regarding proper use and redistribution.
    https://pharos.nih.gov/about
  22. RCSB Protein Data Bank (RCSB PDB)
    LICENSE
    Data files contained in the PDB archive (ftp://ftp.wwpdb.org) are free of all copyright restrictions and made fully and freely available for both non-commercial and commercial use. Users of the data should attribute the original authors of that structural data.
    https://www.rcsb.org/pages/policies
  23. Swiss Institute of Bioinformatics Bgee
    LICENSE
    Creative Commons Zero license (CC0)
    https://www.bgee.org/about/
  24. UniProt
    LICENSE
    We have chosen to apply the Creative Commons Attribution (CC BY 4.0, http://creativecommons.org/licenses/by/4.0/) License to all copyrightable parts of our databases.
    https://www.uniprot.org/help/license
  25. VEuPathDB: The Eukaryotic Pathogen, Vector and Host Informatics Resource
    LICENSE
    All data on VEuPathDB websites are provided freely for public use.
    https://veupathdb.org/veupathdb/app/static-content/about.html
  26. Wikidata
  27. ChEMBL
    LICENSE
    Access to the web interface of ChEMBL is made under the EBI's Terms of Use (http://www.ebi.ac.uk/Information/termsofuse.html). The ChEMBL data is made available on a Creative Commons Attribution-Share Alike 3.0 Unported License (http://creativecommons.org/licenses/by-sa/3.0/).
    http://www.ebi.ac.uk/Information/termsofuse.html
  28. Swiss Institute of Bioinformatics ENZYME
    LICENSE
    Copyrighted by the SIB Swiss Institute of Bioinformatics and distributed under the Creative Commons Attribution (CC BY 4.0) License (https://creativecommons.org/licenses/by/4.0/).
    https://enzyme.expasy.org/enzyme.get
    Enzyme Classification
    https://enzyme.expasy.org/
  29. Gene Ontology (GO)
    LICENSE
    Gene Ontology Consortium data and data products are licensed under the Creative Commons Attribution 4.0 Unported License (https://creativecommons.org/licenses/by/4.0/legalcode)
    http://geneontology.org/docs/go-citation-policy/
  30. AlphaFold DB
    LICENSE
    All of the data provided is freely available for both academic and commercial use under Creative Commons Attribution 4.0 (CC-BY 4.0) licence terms.
    https://alphafold.ebi.ac.uk/faq
  31. Rhea - annotated reactions database
    LICENSE
    Rhea has chosen to apply the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/). This means that you are free to copy, distribute, display and make commercial use of the database in all legislations, provided you credit (cite) Rhea.
    https://www.rhea-db.org/help/license-disclaimer
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