Embryonic stem cells can be derived from the epiblast of pre-implantation or post-implantation embryos. The two resulting pluripotency states called, respectively, naïve and primed present distinct characteristics at numerous levels including metabolism, epigenetic landscape and signaling dependency. To better understand the transition from one state to the other, a CRISPR-Cas9 knockout screen has been performed and previously published. Among several hits, the heme synthesis pathway comes up as essential for naïve-to-primed transition. On this basis, we aim to confirm the heme dependency for the transition and to understand the mechanisms that are affected by heme synthesis inhibition and thus prevent the cells from following their normal naïve-to-primed transition. By inhibiting the heme synthesis, we showed the importance of this biosynthetic pathway for the transition of murine embryonic stem cells. To better understand the role of heme during the transition, we assessed the effect of ROS and NO levels on the transition, the ISR pathway activation and the global protein succinylation on the naïve-to-primed transition. We first showed that ROS and NO level modulation do not seem able to rescue the transition during heme deficiency. Then, we determined that the activation of the ISR during heme deficiency is not the cause of the blockade. Finally, we highlighted that the use of a mitochondrial succinate transporter inhibitor is able to rescue the naïve-to-primed inhibition during heme deficiency by preventing the increase of the global protein succinylation.
|Date of Award||18 Jan 2021|
|Supervisor||Patricia Renard (Supervisor)|
- Embryonic Stem cells
- Naïve state
- Primed state