CTCF is a barrier for 2C-like reprogramming

Teresa Olbrich,Maria Vega-Sendino,Michael J Kruhlak,Raphael Pavani,Wei Wu,Andy D Tran,André Nussenzweig,Mariajose Franco,Gianluca Pegoraro,Catherine N Domingo,Nicholas Zolnerowich,Eros Lazzerini-Denchi,Desiree Tillo,Elphege P Nora,Sergio Ruiz,Peter C Fitzgerald,Marta Markiewicz-Potoczny

doi:10.1038/s41467-021-25072-x

Abstract

Totipotent cells have the ability to generate embryonic and extra-embryonic tissues. Interestingly, a rare population of cells with totipotent-like potential, known as 2 cell (2C)-like cells, has been identified within ESC cultures. They arise from ESC and display similar features to those found in the 2C embryo. However, the molecular determinants of 2C-like conversion have not been completely elucidated. Here, we show that the CCCTC-binding factor (CTCF) is a barrier for 2C-like reprogramming. Indeed, forced conversion to a 2C-like state by the transcription factor DUX is associated with DNA damage at a subset of CTCF binding sites. Depletion of CTCF in ESC efficiently promotes spontaneous and asynchronous conversion to a 2C-like state and is reversible upon restoration of CTCF levels. This phenotypic reprogramming is specific to pluripotent cells as neural progenitor cells do not show 2C-like conversion upon CTCF-depletion. Furthermore, we show that transcriptional activation of the ZSCAN4 cluster is necessary for successful 2C-like reprogramming. In summary, we reveal an unexpected relationship between CTCF and 2C-like reprogramming.

Highlights

Totipotent cells have the ability to generate embryonic and extra-embryonic tissues
Accumulation of DOXinduced ESCDux in the G1 and G2 phases of the cell cycle along with a decrease in DNA replication preceded cell death (Fig. 1b, Supplementary Fig. 2b). To exclude that these effects were due to supra-physiological levels of DUX, we analyzed the unperturbed subpopulation of Embryonic stem cells (ESC) that spontaneously undergoes a 2 cell (2C)-like conversion[3]
Our study demonstrates that 2C-like ESC are unstable in vitro

Summary

Introduction

Totipotent cells have the ability to generate embryonic and extra-embryonic tissues. Interestingly, a rare population of cells with totipotent-like potential, known as 2 cell (2C)-like cells, has been identified within ESC cultures. A rare (~1–2%) transient population of cells with totipotent-like potential was identified within ESC cultures[2,3,4] This cell population expresses high levels of transcripts detected in 2C embryos, including a specific gene set regulated by endogenous retroviral promoters of the MERVL subfamily[2,3,4]. Expression of the transcription factor DUX in ESC is necessary and sufficient to induce a 2C-like conversion characterized by similar transcriptional and chromatin accessibility profiles, including MERVL activation, as observed in 2C-blastomeres[5,6,7] This reprogramming cell model has been instrumental to study the molecular mechanisms that regulate the acquisition and maintenance of totipotent-like features. We demonstrate that the zinc-finger binding protein CTCF, involved in regulating the higher-order organization of chromatin structure, is a barrier in pluripotent cells for 2C-like reprogramming

Methods

Results

Conclusion