Doctorant (M/F) en Biologie

Organisation/Company CNRS Department Laboratoire de Biologie du développement de Villefranche-sur-Mer Research Field Biological sciences Biological sciences » Biology Researcher Profile First Stage Researcher (R1) Application Deadline 23 Sep 2026
- 23:59 (UTC) Country France Type of Contract Temporary Job Status Full-time Hours Per Week 35 Offer Starting Date 1 Oct 2026 Is the job funded through the EU Research Framework Programme? Not funded by a EU programme Is the Job related to staff position within a Research Infrastructure? No

Offer Description

The project will combine approaches of bioinformatics, cell biology, imaging and functional genomics. The candidate will exploit existing tools and resources for Clytia. Live imaging approaches in this highly transparent species will allow the movements of stem cells to be followed. The doctoral candidate will generate bulk and scRNAseq data from young jellyfish gonads, as well as gonozooids (specialised polyps within which the jellyfish develop), for both males and females. They will use immunohistochemical, hybridisation chain reaction (HCR), and EdU approaches to visualize GSCs, pre-meiotic cells, and meiotic germ cells in fixed tissue, and to characterize the appearance of different cell populations within the polyp colony and jellyfish. The function of identified regulator genes can be tested using CRISPR/Cas9 Knockdown.

This PhD project will build on ongoing work in the host lab focussed on the identity and fate of stem cell populations in Clytia. This work indicates that multiple stem cell populations co-exist in the jellyfish, which can be traced back to the specialised polyps that produce jellyfish, including a somatic stem cell population and a potential GSC population. The sex determination aspect is based on an older study using wild Clytia collected from the bay of Villefranche indicating that temperature plays a role in determining sex, acting on young polyp colonies and/or early-stage jellyfish. Specifically, this PhD project will: 1) Define at molecular and cellular levels the germline differentiation trajectory from GSCs to germ cells in both male and female jellyfish and polyp colonies; 2) Pinpoint where and when GSCs (or their precursors) first acquire male or female identities 3) Use freshly-generated 'bipotential' colonies (i.e. ones capable of sex-switching) in order to identify key regulatory genes controlling sexual identity within the germ cell lineage in Clytia.