Changes in the gene expression of pyruvate dehydrogenase kinase isoenzymes during early differentiation of mouse embryonic stem cells

Abstract

The embryonic stem cells (ESCs) are pluripotent, self-renewing cells that are able to differentiate into any of the germ layers involved in embryogenesis. However, the molecular mechanisms that control ESC pluripotency and differentiation remain poorly understood. The family of Pyruvate dehydrogenase kinase (PDK1-4), inactivates the mitochondrial pyruvate dehydrogenase complex via phosphorylation, plays a crucial role in the control of glucose homeostasis. In the current study, gene expression levels of PDK isoenzymes were analyzed on undifferentiated mouse embryonic stem cells (mESCs) and compared to mESCs induced to differentiate by removal of leukemia inhibitory factor (LIF) for 1, 3 and 5 days. Besides, gene expression analysis of several genes related to pluripotency and differentiation were performed by real-time quantitative PCR. In addition, glucose uptake rates in early differentiated and undifferentiated mESCs were determined using a colorimetric assay kit. Differently expression level of PDK isoenzymes in pluripotent and LIF-depleted mESCs suggest that they may have roles in differentiation and pluripotency of ESCs. Furthermore, this study lays the foundation for detailed investigation of molecular mechanisms underlying the roles of PDKs in the pluripotency and transition to differentiated state of ESCs.