Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is well known as one of the key enzymes involved in glycolysis. It catalyzes an important energy-yielding step in carbohydrate metabolism, thereversible oxidative phosphorylation of glyceraldehyde-3-phosphatein the presence of inorganic phosphate and nicotinamide adenine dinucleotide (NAD). Recent evidence suggests that it also is involved in a number of cellular processes such as membrane fusion, phosphotransferase activity, DNA replication and repair, and nuclear RNA export (1). GAPDH has also been implicated in playing a role in different pathologies such as cancer progression, apoptosis, and neuronal diseases such as Alzheimer and Huntington disease (2). GAPDH is constitutively expressed at high levels in almost all tissues and cell lines making it ideal for use as a loading control marker in immunoblots.
