Mots-Clés

transcriptomique transcriptome ARN écologie coraux mer Méditerranée acidification biologie marine

Description

Title : Comparative transcriptomics of Mediterranean coral colonies from natural CO2 vent systems and ambient pH sites.

Supervisors: Nuria Teixido (LOV-IMEV), Steeve Comeau (LOV-IMEV), Richard Copley (LBDV-IMEV)

Duration : 6 months from January 2022

Background

Ocean acidification reflects a suite of changes in seawater chemistry due to the uptake of excess anthropogenic CO2, resulting in a decline in the ocean surface pH, carbonate ion concentration and saturation state of carbonate minerals. Ocean acidification is predicted to have profound implications for marine ecosystems because carbonate ions are an essential substrate for shell and skeleton production. Corals skeletons are of particular concern because they are produced by the accumulation of calcium carbonate. Coral calcification is expected to decrease as seawater acidity increases. Corals create habitats for many species, enhancing biodiversity, playing fundamental ecological roles and sustaining ecosystem processes and services such as fisheries, coastal protection and tourism. There is a population of the coral Astroides calycularis that naturally occurs in a CO2 vent system at the Grotta del Mago in Ischia (Italy). These vent systems, locally acidify the environment and are thus a window of the ocean acidification predicted for the end of the century. The studied species, Astroides calycularis is an endemic Mediterranean scleractinian coral, azooxanthellate and long-lived species that has low dispersal capacities. Studying high CO2 vent systems and their populations represents an opportunity to have new insights into how corals may survive into future conditions of acidification and to reveal if general physiological and genetic mechanisms that confer tolerance can be identified. During this internship, the student will perform differential analysis of gene expression in adult and juvenile corals of Astroides from the field and raised in the laboratory under different pH conditions. RNA expression will be analyzed to assess how many genes, if any, are differentially expressed between acidified and reference pH sites and relate these phenotypic changes to acclimation/adaptation. The Ms student will also establish whether expressed genes are concentrated in specific functional types or are randomly distributed with respect to function across the transcriptome.

Candidate profile:

Bright and motivated Ms candidates in a relevant topic (e.g. marine biology-ecology, genetics). The Ms candidate will combine bioinformatics tools and ecological data. Ideal candidates would have experience of the unix environment and skills in a programming language such as python or R. We have extensive experience of transcriptome analysis and can provide an appropriate level of support, but the ability to work independently towards defined goals and troubleshoot computational problems with online resources is essential. Other ideal skills include the ability to communicate effectively in English, and to work in an interdisciplinary, international research group. The Ms student will learn interdisciplinary discussion with strong emphasis on competence in critical thinking. Internship conditions The student will be hosted at the Institut de la Mer de Villefranche (IMEV), Villefranche-sur-mer, France.

Application procedure

To apply to this internship please send a motivation letter (1 page) and your resume (CV) before the end of October 2021 by email to Núria Teixidó (nuria.teixido@imev-mer.fr), Steeve Comeau (steeve.comeau@imev-mer.fr ), Richard Copley (Richard.Copley@imev-mer.fr)

To know more:

http://4oceansmopga.com/

http://www.marinesciencegroup.org/wp-content/uploads/2014/08/Teixido-et-al-2020-OA-causes-variable-trait-shifts-in-a-coral-species-Global-Change-Biology.pdf