13 ERA-CAPS. Delineating the crossover control networks in plants (DeCOP)

减数分裂是有性生殖所需的一种特殊类型的细胞分裂。在生殖细胞形成之前，它确保了基因组的还原和母系和父系染色体片段的重组。减数分裂重组的过程是由程序性dna双链断裂（DSBs）启动的，由保守的Spo11蛋白引入。最终，dsb的位置定义了相互遗传交换的位点。然而，在单个减数分裂细胞中，只有一小部分dsb注定要形成遗传交叉（COs），而其余的则通过非co途径进行修复。CO的形成本身受到严格的控制，以确保每个同源对至少接收一个专性CO。一种称为CO干扰的现象确保大多数（~85%）额外的CO不会发生在相邻的染色体区域。结果，多个eco沿着同源物分布得很好。了解控制ds2形成和加工形成COs的因素具有重要的科学意义，而且这一知识将对操纵作物减数分裂重组具有重要意义。近年来，植物减数分裂的研究主要集中在鉴定参与重组途径或染色体轴和突触复合体组织的减数基因/蛋白质。尽管这些研究清楚地证明了这些蛋白质的重要性，但它们的活动如何协调以确保co的受控形成仍然是一个谜。因此，这个合作项目（DeCOP）试图将重点转移到如何重组、染色体组织和重塑上，以控制COs的频率和分布。具体来说，我们试图确定决定个体dsb命运的蛋白质网络，并确定CO干扰何时建立。我们建议1)进行创新筛选，以确定调节CO形成和干扰的新因素；2)研究染色体轴相关蛋白在CO成熟和干扰中的作用；3)确定（ATM/ATR介导的）磷酸化在协调减数分裂DNA修复和CO形成中的作用；4)确定参与CO形成最后一步的蛋白质。在DeCOP项目中研究的因素和过程将大大增强我们对控制植物交叉形成的网络的理解。因此，我们预计我们的发现将有力地刺激未来的作物育种计划。

Meiosis is a specialized type of cell division required for sexual reproduction. It ensures the reductionof the genome and the recombination of maternal and paternal chromosomal segments prior to theformation of generative cells. The process of meiotic recombination is initiated by programmed DNAdouble-strand breaks (DSBs), introduced by the conserved Spo11 protein. Ultimately, the positions ofthe DSBs define loci of mutual genetic exchange. However, in a single meiotic cell only a small subsetof DSBs are destined to form genetic crossovers (COs), while the remainder are repaired via non-CO pathways. CO formation itself is subject to stringent control, which ensures that each homologuepair receives at least one obligate CO. A phenomenon known as CO interference then ensures thatmost (~85%) additional COs do not occur in an adjacent chromosomal region. As a result multipleCOs are spaced well apart along the homologues. Understanding the factors that control DSBformation and processing to form COs is of fundamental scientific interest, moreover this knowledgewill have important implications for manipulating meiotic recombination in crop plants.In recent years meiosis research in plants has largely focussed on the identification of meioticgenes/proteins involved in recombination pathways or the organization of the chromosome axes andsynaptonemal complex. Although these studies clearly demonstrate the importance of these proteins, itremained mostly enigmatic how their activities are coordinated to ensure the controlled formation ofCOs. Hence this collaborative project (DeCOP) seeks to shift emphasis to focus on howrecombination, chromosome organisation and remodelling are orchestrated to control the frequencyand distribution of COs. Specifically, we seek to identify the protein networks that determine the fateof individual DSBs and establish when CO interference is established. We propose to 1) perform aninnovative screen to identify novel factors that modulate CO formation and interference, 2) investigatethe role of chromosome axis-associated proteins in CO maturation and interference, 3) determine therole of (ATM/ATR mediated) phosphorylation in coordinating meiotic DNA repair and CO formationand 4) to identify proteins involved in the final step of CO formation.The factors and processes studied in the DeCOP project will significantly enhance ourunderstanding of the networks that govern crossover formation in plants. We therefore anticipate thatour findings will strongly stimulate future crop breeding programmes.