In this project, we are interested in exploring the genetic mechanisms giving rise to obligately parthenogenetic Daphnia. Our previous studies strongly suggest that the genetic incompatibility between two sexual species D. pulex and D. pulicaria is critical for the origin of obligate parthenogenesis in the hybrids of these two species.
In this project, we are investigating the genetic variants regulating meiotic recombination rate variation across Daphnia populations/species and are examining whether meiotic recombination evolves in an adaptive fashion. To estimate recombination rate and identify variants associated with recombination rate variation, we are mainly using and developing single-sperm whole-genome sequencing methodologies and population genomic analysis. We will also use CRISPR-Cas genetic editing to modify genetic variants to examine their effect on recombination rate.
Our lab is actively developing CRISPR-Cas gene editing methodologies for Daphnia, currently including gene knock-out, gene knock-in, and precise base editing. We have a goal of creating 1000 Daphnia mutants in the next 4-5 years and test their gene knock-out effects to gain a deeper understanding of gene function and interactions.
We are interested in understanding the effect of different environmental mutagens, for example, ethyl methanesulfonate (EMS), on the mutation rate and spectrum and gene expression in Daphnia. We use mutant genomic analysis with gene knock-out mutants to understand how different genes contribute to safeguarding genome integrity against the harmful effect of mutagens.
