Coordination of meiotic recombination in diploid and tetraploid arabidopsis

Homologous recombination is an integral part of meiosis and is essential for generating crossovers that ensure balanced segregation of homologous chromosomes and establish genetic variation within offspring. It is therefore exceedingly important that meiotic cells employ stringent control mechanisms to safeguard crossover formation. Work in yeast has indicated that the meiotic axis, a proteinaceous structure that tethers meiotic chromosomes into looped arrays, plays a crucial role in many aspects of homologous recombination, from double strand break formation to crossover interference. It has also been suggested that increased crossover interference helps to establish meiotic stability by inhibiting multivalent formation during autopolyploid meiosis. \nUsing immunocytochemistry coupled with super-resolution microscopy, we have further investigated the role played by the meiotic axis protein ASY1 in stabilising meiosis in the established autotetraploid Arabidopsis arenosa. We have also used Arabidopsis arenosa as a model for studying how meiotic interference might operate within an autopolyploid context. Alongside this, experiments using transgenic lines of the model plant Arabidopsis thaliana have helped to shed light on how crossover formation and synapsis are affected by reduced expression of ASY1 and ASY3 and to determine what effect limiting meiotic crossover numbers might have on neopolyploid meiotic stabilisation.