Abstract: Mouse embryonic stem cells (ESCs) cycle in and out of 2-cell-like (2C-like) state in culture. The molecular mechanism governing the exit of 2C-like state remains obscure, partly due to the lack of a reporter system that can genetically mark intermediate states. Here, we identify an intermediate state that is marked by the co-expression of MERVL::tdTomato and OCT4-GFP (MERLOT) during 2C-like-to-pluripotent state transition. Using this reporter cell line, we systematically identified transcription factors that regulate the transition process from totipotency to pluripotency. Our study identifies a genetically traceable intermediate state during 2C-like-to-pluripotent state transition and provides a valuable tool to study molecular mechanisms regulating the totipotency-to-pluripotency transition in vitro and in vivo.
