PhD position – Role of miRNAs in the control of oocyte reserve in fish (RESOV)

This thesis is part of a research project aiming to decipher the fundamental processes that govern the primary oocyte reserve within the fish ovary, from which mature oocytes (or eggs) are laid during each reproductive cycle. This research will contribute to a better understanding of physiological changes that are relevant to societal issues such as the preservation of wild populations or the improvement of fish farming practices.

The current hypothesis is that, as for mammals, paracrine regulations mediated by factors such as the anti-müllerian hormone (AMH) modulate the reserve status during the female’s life. In the laboratory, we also identified two microRNAs required for the maintenance of the female fecundity in medaka (i.e.the number of eggs laid during each reproductive cycle). We therefore hypothesize that these two miRNAs are also involved, along with AMH, in the regulation of the oocyte reserve and in the control of female fecundity. The objective of the thesis will be to determine the precise role of AMH and of these two miRNAs in the establishment of this reserve in larvae and its renewal in adults, and to understand the underlying mechanisms. To this aim, the candidate will carry out functional in vivo studies using Medaka lines (KO or transgenic) that are maintained at the LPGP. He/she will also create new lines by genome editing to validate potential miRNAs targets (using the CRISPR/Cas9 technology). The candidate will use various phenotyping techniques such as 3D imaging by confocal microscopy (on the LPGP 3D imaging platform) and image analysis based on the use of open-source Deep Learning algorithms. He/she will also use histology techniques such as in situ hybridization (RNAscope technology) or immunhistochemistry (antibodies or nanobodies), as well as transcriptomics approaches (RNA-seq).

Funding: The thesis will benefit from the financial support of the OVOPAUSE project (ANR) and of INRAE (PHASE department).

Laboratory and supervision: The thesis will take place at the Laboratory of Fish Physiology and Genomics (LPGP, INRAE) located on the Beaulieu Campus (University of Rennes) and will be co-supervised by Violette Thermes (LPGP, INRAE) and Frédérique Clément (MUSCA, INRIA, https://team.inria.fr/musca/).

How to apply: Please send a CV and a cover letter to violette.thermes@inrae.fr and frederique.clement@inria.fr.

Skills required: Training in reproductive and developmental biology, and in cellular and molecular biology. Knowledge in microscopy and image analysis will be welcome.

More information:

On the laboratory: https://lpgp.rennes.hub.inrae.fr.

On the proposal: https://lpgp.rennes.hub.inrae.fr/actualites/recrutement-pour-la-these-resov

On the OVOPAUSE project: https://anr.fr/Projet-ANR-22-CE45-0017.