Biology subjects

Joly, T.

Publications and source records attributed to Joly, T..

3 recordsLinked to original sources

bioRxiv2024

Generation of systemic rabbit chimeras via Induced Pluripotent Stem Cells Reprogrammed with KLF2, ERAS, and PRMT6

Little is known about the molecular underpinnings of pluripotent stem cells (PSCs) ability to colonize the epiblast of preimplantation embryos and generate chimeras. In our study, using rabbit PSCs as a model system, we conducted unbiased screening of a cDNA library that encodes a panel of 36 pluripotency factors. From this screening, we identified KLF2, ERAS and PRMT6, whose overexpression confers the ability for self-renewal in a KOSR/FGF2-free culture medium supplemented with LIF, activin A, PKC and WNT inhibitors. The reprogrammed cells acquired transcriptomic and epigenetic features of naive pluripotency, including the reactivation of the 2nd X-chromosome. Leveraging these PSC lines, we determined the transcriptomic signature of embryonic colonization-competence, demonstrating transcriptional repression of genes involved in MAPK, WNT, HIPPO, and EPH signaling pathways, alongside the activation of genes involved in amino-acid metabolism, NF-kB signaling, and p53 pathway. Remarkably, a subset of reprogrammed cells, expressing CD75 at a high level, gained the ability to produce chimeric fetuses with a high contribution from PSCs in all lineages.

cell biology↗

bioRxiv2021

Transcriptomic, epigenetic and metabolic characterization of the pluripotency continuum in rabbit preimplantation embryos

Despite the growing interest in the rabbit model for developmental and stem cell biology, the characterization of embryos at the molecular level is still poorly documented. We conducted a transcriptome analysis of rabbit pre-implantation embryos from E2.7 (morula stage) to E6.6 (early primitive streak stage) using bulk and single-cell RNA-sequencing. In parallel, we studied oxidative phosphorylation and glycolysis and analysed active and repressive epigenetic modifications during blastocyst formation and expansion. We generated a transcriptomic, epigenetic, and metabolic map of the pluripotency continuum in rabbit preimplantation embryos and identified novel markers of naive pluripotency that might be instrumental for deriving naive pluripotent stem cell lines. Although the rabbit is evolutionarily closer to mice than to primates, we found that the transcriptome of rabbit epiblast cells shares common features with that of humans and non-human primates. Summary StatementRabbit preimplantation embryos share characteristics with human and monkey embryos with respect to timing of early lineage segregation and expression of marker genes for naive and primed pluripotency.

developmental biology↗

bioRxiv2020

Primate naive pluripotent stem cells stall in the G1 phase of the cell cycle and differentiate prematurely during embryo colonization

After reprogramming to naive pluripotency, human pluripotent stem cells (PSCs) still exhibit very low ability to make interspecies chimeras. Whether this is because they are inherently devoid of the attributes of chimeric competency or because naive PSCs cannot colonize embryos from distant species remains to be elucidated. Here, we have used different types of mouse, human and rhesus monkey naive PSCs and analyzed their ability to colonize rabbit and cynomolgus monkey embryos. Mouse embryonic stem cells (ESCs) remained mitotically active and efficiently colonized host embryos. In contrast, primate naive PSCs colonized host embryos with much lower efficiency. Unlike mouse ESCs, they slowed DNA replication after dissociation and, after injection into host embryos, they stalled in the G1 phase and differentiated prematurely, regardless of host species. We conclude that human and non-human primate naive PSCs do not efficiently make chimeras because they are inherently unfit to remain mitotically active during colonization.

cell biology↗