Meiosis in Crops
We are interested in the factors that control sexual and asexual reproduction in plant species. In our group we explore how different elements of plant reproduction, including meiosis and fertilization, have been molded and adapted over evolutionary time. We also develop new genetic and genomic technologies that can speed up plant breeding.
During sexual reproduction and the specialized cell division of meiosis, chromosomes recombine leading to new genetic combinations in the next generation. The cultivated tomato (Solanum lycopersicum) and related wild species are a powerful model system to understand fundamental aspects of plant meiosis. Wide interspecific hybrids are viable, yet crossover suppression between homeologous (partially homologous) chromosomes is a major post-zygotic barrier to genetic exchange between related species and limits the amount of genetic diversity that is accessible to plant breeders. We work on understanding the genetic and epigenetic components of this suppression. Our group uses genomics, genome editing and super-resolution microscopy to read, rearrange and image chromosomes during tomato meiosis.
In contrast to sexual reproduction, asexual reproduction by apomixis, leads to offspring that are genetically identical to the mother plant – they are clones. Apomixis has evolved recurrently in diverse plant families yet less than 0.1% of plant species reproduce via apomixis. Natural apomixis allows the fixation of hybrid, often polyploid, genotypes for successive generations. Apomixis is especially common in the sunflower family and we have previously isolated a natural apomixis gene, PARTHENOGENESIS, from the common dandelion (Taraxacum officinale). Remarkably, hawkweed (Pilosella piloselloides (formerly Hieracium)), a distant relative of dandelion, hijacked the same gene, in an independent event, to evolve asexual reproduction. Our group is interested in the mechanisms of natural apomixis and the development of synthetic apomixis systems in crops.