ZFP560 facilitates KAP1-dependent chromatin repression to regulate exit from totipotency

KRAB zinc finger proteins (KRAB-ZFPs) are the most abundant transcriptional regulators and epigenetic repressors in mammals and contribute to the silencing of transposable elements (TEs) during embryonic development. However, the early effectors of the KRAB-ZFP family during embryonic development and cell state transition remain largely unexplored. Here, we identify that zinc finger protein 560 (ZFP560) is involved in the regulation of early embryonic development and the transition from totipotency in mice. ZFP560 safeguards heterochromatin structure by recruiting KAP1 to facilitate the exit of totipotency. The deficiency of ZFP560 disrupted heterochromatin formation, significantly halting the transition from totipotency to pluripotency. Similarly, the overexpression of ZFP560 promotes exit from the MERVL-positive state and suppresses expression of 2-cell (2C) transcription factors by recruiting KAP1 via its KRAB domain, thereby reducing chromatin accessibility. Taken together, these findings reveal that ZFP560 is a highly expressed 2C-specific KRAB-ZFP transcription factor and a mediator that facilitates the exit from totipotency, providing insights into the epigenetic regulation of early embryonic development.