Lucas Prost

In November 2020 I obtained a PhD fellowship fundamental research from FWO (Fonds Wetenschappelijk Onderzoek) with the title “When Genomes Team Up”. The goal of the project is to investigate the immediate effects of allopolyploidization on fitness and gene expression. Allopolyploidization is an important phenomenon in plants that combines genome duplication and genome merging (i.e., polyploidization and hybridization). Allopolyploid plants have been described as “general purpose phenotype” by G. L. Stebbins, and indeed they seem to have a greater ability to exploit novel habitat than their diploid relatives. The most common hypothesis to explain this observation is the higher genetic diversity of allopolyploids, which they could use to respond to different conditions. Recently, this hypothesis has been reformulated in transcriptomic terms: allopolyploids can employ either adaptive homoeolog or either ecological parental expression level in response to environmental conditions, thus expanding their ecological amplitude across the parental niches. This hypothesis has been called the polyploid plasticity hypothesis in the literature, but I suggest the name of allopolyploid plasticity hypothesis.
Using the haploid species Chlamydomonas reinardtii, I intend to put this hypothesis to test in laboratory controlled conditions. I will merge different strains which will have evolved in different conditions during a laboratory adaptation experiment or which will come from different natural genetic clusters. These newly formed ‘allodiploid’ hybrids will be compared to their haploid parents for fitness and gene expression.