Beta-galactosidase (GLB1) (GLB1)

Beta-galactosidase is a critical lysosomal hydrolase encoded by the GLB1 gene, primarily responsible for cleaving terminal beta-galactose residues from substrates such as GM1 gangliosides and keratan sulfate. Mutations in the GLB1 gene lead to the accumulation of these substrates, resulting in severe lysosomal storage disorders including GM1 gangliosidosis, which causes progressive neurodegeneration, and Morquio syndrome type B, which is characterized by systemic skeletal abnormalities. Beyond its enzymatic role, an alternatively spliced isoform of GLB1 serves as an elastin-binding protein (EBP) essential for the proper assembly of elastic fibers in connective tissues. In the context of aging and oncology, a specific activity level known as senescence-associated beta-galactosidase (SA-beta-gal) is widely utilized as a biomarker for cellular senescence. Current therapeutic development focuses on gene therapies to provide a functional GLB1 transgene and pharmacological chaperones designed to restore the stability and activity of mutant enzyme forms.

Other names

Acid beta-galactosidaseGalactosidase beta 1Elastin-binding proteinEBPELNR1LactaseMPS4B

Therapeutic strategies include gene therapy to restore functional enzyme expression, pharmacological chaperone therapy to stabilize misfolded mutant proteins, and substrate reduction therapy to decrease the accumulation of toxic metabolites like GM1 gangliosides.