Investigating the control of inter-homologue recombination and synapsis during meiosis in Arabidopsis thaliana

• Main Author: Ferdous, Maheen
• Published: University of Birmingham 2013
• Subjects: 500; QH301 Biology
• Online Access: https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.569723

During meiosis, axis formation and synapsis of homologous chromosomes are tightly co-ordinated with meiotic recombination. This study investigates the influence of chromosome axis and synaptonemal complex proteins on meiotic crossover formation. The study involved the characterization of a novel protein, AtASY3, required for normal meiosis in Arabidopsis. Analysis of Atasy3 mutants revealed that loss AtASY3 compromises chromosome axis formation, synapsis and normal levels of crossover formation. Further analysis revealed that loss of AtASY3 disrupts the axial organization of AtASY1. In separate studies, colleagues found that AtASY3 and AtASY1 are able to interact. Together, these results suggest that AtASY3 is a functional homologue of the budding yeast axis protein, Red1. Since studies in budding yeast indicate that Red1 and Hop1 (homologue of AtASY1) play a key role in establishing a bias to favour inter-homologue recombination, this study suggests that AtASY3 and AtASY1 may have a similar role in Arabidopsis. The study also involved the analysis of the putative phosphorylation site, residue T295, on AtASY1. This revealed that T295 is essential for AtASY1-mediated crossover formation during meiosis. Additionally, a potential meiotic role for the RECQ DNA helicase, AtRECQ4B was investigated, however, the protein does not appear to be essential for Arabidopsis meiosis.