What kind of enzyme is GAPDH?
Glyceraldehyde 3-phosphate dehydrogenase (abbreviated GAPDH) (EC 1.2. 1.12) is an enzyme of about 37kDa that catalyzes the sixth step of glycolysis and thus serves to break down glucose for energy and carbon molecules.
What is the normal function of GAPDH?
Glyceraldehyde 3-phosphate dehydrogenase (GAPDH) is an enzyme involved in breaking down glucose to obtain energy. More specifically, in eukaryotes, this enzyme catalyzes the sixth step in glycolysis, converting glyceraldehyde 3-phosphate to D-glycerate 1,3-bisphosphate (1,3-BPG).
Why is GAPDH so important?
Abstract. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) has long been recognized as an important enzyme for energy metabolism and the production of ATP and pyruvate through anaerobic glycolysis in the cytoplasm. Recent studies have shown that GAPDH has multiple functions independent of its role in energy metabolism.
Is GAPDH a transcription factor?
GAPDH is the target of different transcription factors, and various control regions have been identified in its promoter, including hypoxia and insulin-responsive elements22, 23 (Figure 1). In the context of cancer, hypoxia is of particular interest.
What produces GAPDH?
The key function of GAPDH is attributed to glycolysis, which means that the active tetrameric molecule catalyzes the conversion of glyceraldehyde-3-phosphate to 1,3-bisphospho-d-glycerate [80].
Where is GAPDH found?
In addition to the cytoplasm where majority of GAPDH is located under the basal condition, GAPDH is also found in the particulate fractions, such as the nucleus, the mitochondria, and the small vesicular fractions. When cells are exposed to various stressors, dynamic subcellular re-distribution of GAPDH occurs.
Why GAPDH is a housekeeping gene?
GAPDH is a key regulatory enzyme, which catalyzes the oxidative phosphorylation of glyceraldehyde-3-phosphate during glycolysis. β-actin is a cytoskeletal protein involved in cell structure and motility. Based on these basic and ubiquitous cellular functions, GAPDH and β-actin are considered as housekeeping genes.
Is GAPDH in all organisms?
Amongst these proteins / enzymes, the glyceraldeyde-3-phosphate dehydrogenase (GAPDH) is present in all living organisms, as the key enzyme in glycolysis, the common pathway both in organ- isms that live in free oxygen and the ones that do not.
What are the other physiological functions of GAPDH?
Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is an energy metabolism-related enzyme in the glycolytic pathway. Recently, it has been reported that GAPDH has other physiological functions, such as apoptosis, DNA repair and autophagy.
What is the role of GAPDH in glycolysis?
The key function of GAPDH is attributed to glycolysis, which means that the active tetrameric molecule catalyzes the conversion of glyceraldehyde-3-phosphate to 1,3-bisphospho-d-glycerate [80]. Chemical modifications and denaturation of GAPDH can slow down the glycolytic cycle and disrupt the cellular metabolism [81].
Why is GAPDH a good housekeeping gene?
Why is GAPDH used as a control in qPCR?
As one of the most common reference genes, GAPDH is often used to normalize the gene expression data, being used as an endogenous control in the quantitative analysis of RT-PCR, since in some experimental systems, its expression is very constant (Edwards and Denhardt 1985; Winer et al. 1999).
Why is GAPDH used as a reference gene?
To date, cancer researchers have predominantly used the GAPDH and β-actin reference genes as internal reference controls, because their mRNA expression levels are established to be high and constant in many different cells and tissues [4, 5].