Temporal and spatial expression of glyceraldehyde 3-phosphate dehydrogenase (Gapdh) in the mouse placenta.

Glucose metabolism in trophoblast cells is essential to provide the required energy for the development and function of the placenta. Glyceraldehyde 3-phosphate dehydrogenase (Gapdh), a key enzyme in the glycolysis pathway has been considered ubiquitously expressed in cells. There is, however, a growing body of evidence suggesting that Gapdh has many functions in pathways unrelated to glucose metabolism. In the present study, we show that GAPDH expression and sub-cellular localization changes through gestation in the mouse placenta. Our findings raise the possibility that GAPDH has multiple functions in trophoblast cells and the developing placenta, while also cautioning against its use as an endogenous reference or standard for gene expression in the placenta.