Project description
Consequences of haploid selection in animal evolution
Sexual reproduction is a nearly universal feature of eukaryotic organisms. Selection occurring during the haploid gametic phase of any sexually reproduced eukaryote may have extensive consequences for major biological processes. Studies show strong links between sperm phenotype and offspring fitness and between sperm phenotype and its haploid genotype. The ERC-funded SELECTHAPLOID project will combine carefully designed innovative experimental methods with advanced single-cell genome and transcriptome sequencing technologies to provide novel insights into the process that characterises all eukaryotic life. The findings will shed light on the haploid phase and the mechanisms that maintain genetic variation in genes expressed. It will also explore how haploid selection affects the interaction between male and female gametes.
Objective
Selection occurring during the haploid gametic phase of any sexually reproducing eukaryote may have far-reaching consequences for major biological processes. Selection acting on a haploid genome results in efficient removal of deleterious alleles and rapid fixation of beneficial alleles, which in turn affect adaptation, genetic load and the evolution of recombination rates. Despite their potential importance, we know surprisingly little about the genetic processes occurring during the time window after meiosis until the fusion of male and female pronuclei. This is particularly true for haploid selection in the gametes of predominantly diploid animals. Male gametes (sperm) are produced in vast numbers but only few fertilise eggs and therefore offer a strong opportunity for selection. A prevailing view that such haploid selection is of minimal consequence in animals has been recently overturned by evidence from our lab, which revealed strong links between sperm phenotype and offspring fitness, as well as sperm phenotype and its haploid genotype. The genetic mechanisms underlying these observations are currently poorly understood. In this project, I will tackle three key questions arising from these recent findings: i) How strong are purifying and positive selection during the haploid phase? ii) What are the mechanisms maintaining genetic variation in genes expressed during the haploid phase? iii) How does haploid selection affect the interaction between male and female gametes? By combining carefully designed innovative experimental approaches with cutting-edge single-cell genome and transcriptome sequencing technologies, this project will provide entirely novel insights into the process that is shared by all eukaryotic life. Findings from this project will illuminate not only the fields of evolutionary biology and genetics but far beyond into the areas of animal breeding and human reproduction.
Fields of science
Programme(s)
Funding Scheme
ERC-COG - Consolidator GrantHost institution
NR4 7TJ Norwich
United Kingdom