Faites connaître cette offre !
Reference : UMR7622-JEAGIB-001
Workplace : PARIS 05
Date of publication : Wednesday, May 20, 2020
Scientific Responsible name : Jean-Michel Gibert et Amandine Véber
Type of Contract : PhD Student contract / Thesis offer
Contract Period : 36 months
Start date of the thesis : 1 October 2020
Proportion of work : Full time
Remuneration : 2 135,00 € gross monthly
Description of the thesis topic
In Drosophila melanogaster, abdominal pigmentation is genetically variable and a few genes with major effects on this trait have been identified in natural populations. Moreover, abdominal pigmentation shows phenotypic plasticity. Indeed, it is darker when flies develop at low temperatures. Previous studies have shown in other insects that dark individuals warm up more rapidly and are more active. The project aims to test the role of drosophila pigmentation in temperature adaptation using an integrative approach combining mathematical modelling, simulations and laboratory experiments.
The temperature of differently pigmented drosophila illuminated by light that mimics sunlight will be analysed by calorimetry using a thermal camera that can detect minute differences in temperature. Similarly, the motor activity of differently pigmented drosophila will be quantified and analysed. In addition, it is possible to indirectly test an adaptive role of abdominal pigmentation by analysing variations in the frequency of alleles of genes involved in this trait in response to temperature variations. For this, the PhD student will model the variations in allele frequencies of a small number of genes involved in pigmentation in response to spatial (latitude) and temporal (seasonal) temperature variations, taking into account that abdominal pigmentation has both genetic and environmental bases. The results of the modelling will be compared with data from natural populations through the DrosEU consortium, which is sequencing Drosophila melanogaster populations sampled at different locations and times in Europe.
Expected results :
This integrative approach should lead to a better understanding of the role of drosophila abdominal pigmentation in temperature adaptation. Modelling and analysis of natural population data will allow to assess the relative contributions of genetic variation and phenotypic plasticity in temperature adaptation. Indeed, both phenotypic plasticity and maintenance of genetic variation by balancing selection in response to temperature can contribute to spatial and temporal variation in pigmentation.
This project will take place between the laboratories of the Ecole Polytechnique (Palaiseau) and the Institut de Biologie Paris-Seine (Paris) under the direction of Amandine Véber (CRCN CNRS, Centre de Mathématiques Appliquées de l'Ecole Polytechnique) and Jean-Michel Gibert (CRCN CNRS, Laboratoire de Biologie du Développement, IBPS, Sorbonne Université CNRS). Collaborators specialised in calorimetry (Philippe Cristol, Institute of Electronics and Systems, Montpellier), modelling of phenotypic plasticity (Luis-Miguel Chevin, Centre d'écologie fonctionnelle et évolutive, Montpellier), mathematical modelling (Sylvie Méléard, Centre de Mathématiques Appliquées de l'Ecole Polytechnique, Palaiseau) and analysis of the activity and ageing of fruit flies (Michaël Rera, Centre de Recherche Interdisciplinaire, Paris) will support the project. The three-year thesis contract is funded by the CNRS, through the Mission for Transverse and Interdisciplinary Initiatives (MITI).
Constraints and risks
No specific constraints and risks
The candidate must hold a master's or engineering degree. A strong motivation for mathematical modelling is required as well as a minimum knowledge of modelling tools. The position requires good oral and written communication skills (English required). We are looking for a curious and enthusiastic young researcher who will be able to work in a team on multidisciplinary projects. Applications should include a detailed CV, at least two references (who may be contacted), a one-page cover letter, a one-page summary of the master thesis and grades from Master 1 and 2 or engineering school
We talk about it on Twitter!