The Regulation of Chromosome Axis formation in Plant Meiosis

在所有有性繁殖的真核生物中，减数分裂重组对于维持物种的倍性水平和引入遗传变异是必不可少的。两者都需要在减数分裂期间形成的遗传杂交（COs）。CO形成的第一步是DNA中双链断裂（DSBs）的产生。在许多物种中，产生的dsb的数量远远超过最终分解的co的数量；在拟南芥中，大约5%的dsb会变成COs。以前已经阐明了对一氧化碳频率和分布的几个层次的控制。在许多谷物品种中，如小麦，这些对重组的严格控制导致植物育种者无法获得高达50%的遗传信息。目前还不完全清楚CO的决定是如何做出的，但我们知道，在减数分裂期间，重组机制、染色体轴和染色体整体重塑之间的相互作用是至关重要的。因此，如果我们要了解如何操纵减数分裂重组，并使作物育种者更快地培育出新的、改良的品种，研究染色体轴在减数分裂中的作用是必不可少的。通过结合创新的分子和细胞遗传学技术，该博士项目旨在进一步了解染色体轴在减数分裂中的作用，以及个体蛋白质是如何被调节的。这将包括对蛋白质-蛋白质相互作用和转录后修饰的研究，这些修饰可能影响几种核心轴蛋白的调节和作用，以及使用超分辨率显微镜更详细地观察轴。

In all sexually reproducing eukaryotes, meiotic recombination is essential for the maintenance of the ploidy level of the species, and the introduction of genetic variation. Both require genetic crossovers (COs) formed during meiosis. The first step in CO formation is the production of double strand breaks (DSBs) in DNA. In many species, the number of DSBs produced far outweighs the number of COs that eventually resolve; in Arabidopsis thaliana, approximately 5% of DSBs will become COs. Several levels of control on CO frequency and distribution have previously been elucidated. In many cereal species such as Wheat, these stringent controls on recombination result in up to 50% of the genetic information being inaccessible to plant breeders. It is still not fully understood how the decision to make a CO is made, but it is known that the interaction between the recombination machinery, the chromosome axis, and the global remodelling of chromosomes during meiosis is crucial. Investigating the role of the chromosome axis in meiosis is therefore essential if we are to learn how we might manipulate meiotic recombination, and allow crop breeders to more rapidly develop new, improved cultivars. Through a combination of innovative molecular and cytogenetic techniques, this PhD project aims to further our understanding of the role of the chromosome axes in meiosis, and how individual proteins are regulated. This will include investigation of the protein-protein interactions and post-transcriptional modifications that may influence the regulation and role of several core axis proteins, as well as the use of super-resolution microscopy to visualise the axis in greater detail.