InterPro domain: IPR000447

FAD-dependent glycerol-3-phosphate dehydrogenase (G3PDH; 1.1.5.3 ) catalysesthe conversion of glycerol-3-phosphate into dihydroxyacetone phosphate: sn-glycerol-3-phosphate + a quinone = glycerone phosphate + a quinol Insulin exposure often stimulates G3PDHactivity [ 1 , 2 ], and thus is key to reducing the effects of the diseasediabetes. In obese people, where insulin resistance has been demonstrated,the amount of G3PDH has been shown to be correspondingly lower thanthat in normal weight people [ 3 ].In bacteria [ 3 ] it is associated with the utilization of glycerol coupled torespiration. In Escherichia coli and Haemophilus influenzae, two isozymes are known: one expressed underanaerobic conditions (gene glpA) and one in aerobic conditions (gene glpD). Ineukaryotes, a mitochondrial form of GPD participates in the glycerol phosphateshuttle in conjunction with an NAD-dependent cytoplasmic GPD ( 1.1.1.8 ) [ 4 , 5 ]. This mechanism is responsible forthe preservation of a redox balance [ 6 , 7 ]. In this environment, the enzymehas been recorded to increase activity in the presence of calcium [ 8 ].These enzymes are proteins of about 60 to 70 Kd which contain a probableFAD-binding domain in their N-terminal extremity. The mammalian enzyme differsfrom the bacterial or yeast proteins by having an EF-hand calcium-bindingregion (see PDOC00018 ) in its C-terminal extremity.

1. Glycerol-3-phosphate dehydrogenase activity in human lymphocytes: effects of insulin, obesity and weight loss. Biochem. Biophys. Res. Commun. 207, 183-90
2. Genetic mapping and chromosome localization of the rat mitochondrial glycerol-3-phosphate dehydrogenase gene, a candidate for non-insulin-dependent diabetes mellitus. Genomics 38, 96-9
3. Nucleotide sequence of the glpD gene encoding aerobic sn-glycerol 3-phosphate dehydrogenase of Escherichia coli K-12. J. Bacteriol. 173, 101-7
4. GUT2, a gene for mitochondrial glycerol 3-phosphate dehydrogenase of Saccharomyces cerevisiae. Yeast 9, 1121-30
5. Sequence of rat mitochondrial glycerol-3-phosphate dehydrogenase cDNA. Evidence for EF-hand calcium-binding domains. J. Biol. Chem. 269, 14363-6
6. Regulation of adenine nucleotide translocase and glycerol 3-phosphate dehydrogenase expression by thyroid hormones in different rat tissues. Biochem. J. 317 ( Pt 3), 913-8
7. The importance of the glycerol 3-phosphate shuttle during aerobic growth of Saccharomyces cerevisiae. Yeast 14, 347-57
8. Calcium activation of mitochondrial glycerol phosphate dehydrogenase restudied. Arch. Biochem. Biophys. 326, 79-84