Skip to Main content Skip to Navigation
Theses

Genetic and epigenetic mechanisms of the regulation of mouse embryonic stem cells self-renewal by the pluripotency transcription factor Nanog

Abstract : Mouse embryonic stem (ES) cells are derived from the pre-implantation blastocyst and are able to maintain pluripotency through limitless cell divisions in vitro. The study of the specific features of ES cells led to the discovery of the transcription factors (TFs) governing their unique transcriptome. Among those TFs, Nanog plays a central role in supporting ES cells self-renewal. Yet, the molecular mechanisms by which Nanog exerts its functions are not fully elucidated. We adapted an inducible CRISPR activation (CRISPRa) system in mouse ES cells and demonstrated its functionality to activate endogenous loci. We determined the list of Nanog responsive genes using gain (CRISPRa) and loss of function experiments. The DNA binding profiles of distinct pluripotency TFs were assessed genome-wide upon Nanog depletion and revealed its importance in the regulation of the pluripotency network activity at thousands of loci where it employs different mechanisms to activate and repress its targets. We expanded the list of Nanog responsive genes in the absence of LIF and found that Nanog-dependent repression is strongly correlated with H3K27me3 enrichment at target loci such as Otx2, a key differentiation factor. We then explored the regulation of long non-coding RNAs expression by Nanog and selected candidates that could potentially be involved in the maintenance of ES cell self-renewal. One of them already gave promising results. Finally, a fortuitous off-target effect of CRISPRa led to the induction of the 2C-like state spontaneously found in a subset of ES cells. Off-target binding sites were determined genome-wide and candidate genes are now under investigation.
Complete list of metadatas

Cited literature [623 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-02864835
Contributor : Abes Star :  Contact
Submitted on : Thursday, June 11, 2020 - 12:35:27 PM
Last modification on : Tuesday, June 30, 2020 - 5:08:02 PM

File

these_HEURTIER_Victor_2018.pdf
Version validated by the jury (STAR)

Identifiers

  • HAL Id : tel-02864835, version 1

Citation

Victor Heurtier. Genetic and epigenetic mechanisms of the regulation of mouse embryonic stem cells self-renewal by the pluripotency transcription factor Nanog. Cellular Biology. Sorbonne Université, 2018. English. ⟨NNT : 2018SORUS306⟩. ⟨tel-02864835⟩

Share

Metrics

Record views

73

Files downloads

50