Genome size can have an impact on various aspects of plant biology, including gene expression, development, and adaptation to different environments (Knight and Beaulieu, 2008). However, the relationship between genome size and phenotypic traits in plants is complex and not fully understood (Elliott and Gregory, 2015).
Genome size can affect gene expression and regulation, which in turn can influence phenotypic traits. For example, some studies have suggested that larger genomes may be associated with greater gene redundancy and functional diversity, which could confer greater adaptability and resilience to environmental stresses (Benett and Leitch, 2005).
Additionally, genome size can affect the rate of mutation and recombination, which can lead to genetic variation and potentially influence phenotypic traits. Some studies have suggested that plants with larger genomes may be more likely to undergo polyploidization, which can lead to rapid evolution and the acquisition of novel traits (Pellicer et al., 2018).
Overall, the relationship between genome size and phenotypic traits in plants is complex and multifaceted, and further research is needed to fully understand the mechanisms underlying this relationship.
One of the most well-known effects of genome size on plant phenotype is the correlation between genome size and cell size. In general, plants with larger genomes tend to have larger cells, and this can affect traits such as leaf size, plant height, and fruit size through allometric relationships (Vasseur et al., 2022). This suggests that genome size and its determinants (e.g., gene content, rDNA copy number, presence/absence of chromosomal regions, structural variants, etc.) could vary in response to selection
However, genome size variation at the intraspecific level remains poorly understood. The objectives of the proposed postdoctoral fellowship are to (1) examine how does genome size vary between different ecotypes of the model plant species Arabidopsis thaliana, (2) test whether genome size variation impacts cell size and other phenotypic traits at higher organizational scales, (3) test the heritability of genome size.
Activities Genome size will be measured on a set of chosen ecotypes with the latest long-read sequencing technologies (PacBio and/or MinION Nanopore). In addition, phenotypic data at various organizational scales in Arabidopsis thaliana are already available in the host laboratory.
These data include cellular characteristics (e.g., cell size, total RNA and ribosomal RNA concentration, mitochondrial and chloroplast abundance), leaf characteristics (e.g., leaf area, fresh and dry mass, width and length, cell number, epidermal cell area and stomatal density, specific leaf area, and leaf dry matter content), as well as whole plant characteristics (e.g., leaf and stem biomass, plant height, number of leaves, flowering time, reproductive investment).
These phenotypic data were collected on a large set of previously sequenced genotypes from contrasting environments. The relationships between traits will be studied using models and equations from the field of allometry. Finally, multivariate approaches will be used to describe the phenotypic integration from the genome to the whole plant phenotype (PCA, hypervolume, structural equation modeling and network analysis).
Skills We are looking for a motivated candidate with a strong interest in genomics, functional ecology, evolutionary biology and genetics. We are open to applications from people with different backgrounds, but we are particularly looking for a postdoc with bioinformatic and statistical analysis skills, combined with a good experience and a taste for scientific writing.
Work Context The postdoc will be assigned to the Centre d’Ecologie Fonctionnelle et Evolutive (CEFE, UMR5175, CNRS Montpellier) within the ECOPAR team, and will be supervised by François Vasseur and Cyrille Violle. The postdoc will be funded in the framework of an ERC project led by François Vasseur (PHENOVIGOUR project).
Offer title : Postdoc (M/W) in plant ecologie and evolution (H/F)
Reference : UMR5175-FRAVAS-012
Number of position : 1
Workplace : MONTPELLIER
Type of Contract : FTC Scientist
Contract Period : 24 months
Expected date of employment : 1 October 2023
Proportion of work : Full time
Remuneration : Between 2800€ and 3200€ gross monthly depending on experience
Desired level of education : Niveau 8 – (Doctorat)
Experience required : Indifferent
Section(s) CN : Biodiversity, evolution and biological adaptations: from macromolecules to communities