Glyceraldehyde 3-Phosphate Dehydrogenase (GAPDH) is a ubiquitous enzyme involved in glycolysis, converting glyceraldehyde-3-phosphate into 1,3 diphosphoglycerate. This constitutively expressed, homotetramer protein can be found in the nucleus and cytoplasm, and the monomer has a theoretical molecular weight of 36 kDa. Known as a housekeeping gene, GAPDH routinely serves as a control for real-time PCR (RT-PCR) and as a loading control for Western Blots (1-3). In addition to its role in glycolysis, GAPDH has multiple cellular functions including membrane trafficking, transcription activation, apoptosis, DNA repair, and has been implicated in various pathologies such as cancer and neurodegenerative diseases including Alzheimer's and Huntington's (4,5).
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5) Tristan C, Shahani N, Sedlak TW, Sawa A. (2011) The diverse functions of GAPDH: views from different subcellular compartments. Cell Signal. 23(2):317-23. PMID: 20727968