Henderson Group: Unlocking recombination in plant genomes via epigenetic modification
Supervisor
Professor Ian Henderson
Summary
During meiosis homologous chromosomes physically pair and undergo reciprocal exchange, called crossover. Recombination is a fundamental process that shapes genetic diversity in plants and animals. It also remains a vital tool for crop improvement and breeding. Interestingly, crossover frequency is highly variable along chromosomes and chromatin and epigenetic information play a key role determining this. In this project the student will modify the epigenome of the model plant Arabidopsis and test the effects on meiotic recombination. Our laboratory uses fluorescent reporters to monitor crossover recombination, and in this rotation the student will combine these with mutants that change epigenetic marks, including DNA methylation. Particular focus will be given to the centromeric regions, which are highly repetitive and suppressed for both gene transcription and recombination. Therefore, the student will test whether reduction in DNA methylation unlocks recombination in these regions. This project will provide the student with an advanced training in genetics, epigenetics, genomics and molecular biology. Opportunities also exist to translate these findings into crop species, including tomato and wheat. Molecular assays designed to detect and quantify DNA methylation will be performed to correlate with levels of meiotic recombination measured with the fluorescent reporters.
Selected publications
Choi, et al. (2018) 'Nucleosomes and DNA methylation shape meiotic DSB frequency in Arabidopsis transposons and gene regulatory regions' Genome Research 28: 532-546.
Underwood, et al (2018) 'Epigenetic activation of meiotic recombination in Arabidopsis centromeres via loss of H3K9me2 and non-CG DNA methylation' Genome Research 28: 519-531.
Choi, K., et al (2013) 'Meiotic crossover hotspots overlap with H2A.Z nucleosomes at Arabidopsis gene promoters.' Nature Genetics (2013) 45: 1327-1336.