Increased expression of 6-phosphofructo-2-kinase/fructose 2,6-bisphosphatase-3 is required for proliferation of mouse embryonic stem cells that are undergoing differentiation

Abstract: The unlimited proliferation capacity of embryonic stem cells (ESCs) coupled with their capability to differentiate into several cell types makes them an attractive candidate for studying the molecular mechanisms regulating self renewal and transition from pluripotent state. Although the roles of 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase family (PFKFB1-4) in cell survival, proliferation, and differentiation in tumor cells have been studied, their role in mESCs biology is currently unkown. In the current study, Pfkfb isozyme expressions were analyzed in undifferentiated R1 and J1 mouse embryonic stem cells (mESCs) that were cultured in the presence and absence of leukemia inhibitory factor (LIF). We report that expression of the Pfkfb3 isoenzyme was markedly increased when mESCs were promoted to differentiate with LIF removal. We then demonstrated that Pfkfb3 silencing induced the differentiation marker Brachyury suggesting that Pfkfb3 may be required for the regulation of mesodermal differentiation of mESCs. Furthermore, we show that the increase in Pfkfb3 expression is required for the proliferation of early differentiated mESCs. Although these results provide important insights into the early differentiation of mESCs with regard to Pfkfb expressions, further mechanistic studies will be needed for understanding the pathways and mechanisms involved in regulation of proliferation and early differentiation of mESCs through Pfkfb3.