Glyceraldehyde-3-phosphate dehydrogenase (GAPDH)

Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is a catalytic enzyme commonly known to be involved in glycolysis. The enzyme exists as a tetramer of identical 37 kDa subunits. GAPDH catalyzes the reversible reduction of 1,3– bisphos-phoglycerate to glyceraldehyde 3– phosphophate in the presence of NADPH. Apart from playing a key role in glycolysis, this ubiquitously expressed enzyme also displays other activities unrelated to its glycolytic function. GAPDH is reported to be involved in the processes of DNA replication, DNA repair, nuclear RNA export, membrane fusion and microtubule bundling. Other studies also provide evidence of GAPDH playing an essential part of the program of gene expression observed in apoptosis and as part of the cellular phenotype of age-related neurodegenerative diseases.