Beta-hexosaminidase subunit alpha (Hex A)

Beta-hexosaminidase subunit alpha is the protein product of the HEXA gene in humans, forming part of the lysosomal enzyme beta-hexosaminidase A. The functional enzyme is a heterodimer of one alpha subunit (HEXA) and one beta subunit (HEXB) and is essential for breaking down GM2 ganglioside, a glycolipid found in neuronal membranes. Deficiency or dysfunction of the alpha subunit results in the accumulation of GM2 ganglioside, notably in the central nervous system, leading to the fatal neurodegenerative disorder Tay-Sachs disease. The alpha subunit forms a distinct active site capable of hydrolyzing specific substrates that the beta subunit cannot, and mutations in HEXA can have effects ranging from severe, rapid-onset infantile disease to milder, late-onset forms. The subunit is a member of the glycosyl hydrolase family, is subject to post-translational modification, and is a focus of research for gene therapy and enzyme replacement treatments for lysosomal storage disorders.

Other names

Beta-hexosaminidase Ahexosaminidase A (alpha polypeptide)N-acetyl-beta-glucosaminidaseHEXA_HUMANbeta-N-acetylhexosaminidase A

Enzyme replacement therapy: supplement functional HexA enzyme to compensate for genetic deficiency; Substrate reduction therapy: reduce levels of ganglioside GM2 to slow disease progression; Gene therapy: delivery of functional HEXA gene for enzyme restoration