Abstract
Activation of signal transducer and activator of transcription 3 (Stat3) by leukemia inhibitory factor (LIF) is required for maintaining self-renewal and pluripotency of mouse embryonic stem cells (mESCs). Here, we have confirmed transcription factor Forkhead Box m1 (Foxm1) as a LIF/Stat3 downstream target that mediates LIF/Stat3-dependent mESC self-renewal. The expression of Foxm1 relies on LIF signaling and is stimulated by Stat3 directly in mESCs. The knockdown of Foxm1 results in the loss of mESC pluripotency in the presence of LIF, and the overexpression of Foxm1 alone maintains mESC pluripotency in the absence of LIF and feeder layers, indicating that Foxm1 is a mediator of LIF/Stat3-dependent maintenance of pluripotency in mESCs. Furthermore, the inhibition of Foxm1 expression prevents the reprogramming of mouse embryonic fibroblasts to induced pluripotent stem cells (iPSCs), suggesting that Foxm1 is essential for the reprogramming of somatic cells into iPSCs. Our results reveal an essential function of Foxm1 in the LIF/Stat3-mediated mESC self-renewal and the generation of iPSCs.