Genetic and molecular analysis of epistatic interactions in flowering time pathways identified in a barley multi-parent advanced generation intercross (MAGIC) population

该建议所基于的假设：基于MAGIC的群体构成了上位效应的遗传分析和鉴定基因的坚实基础，这些基因通过互补或增强彼此的正向相互作用或一个位点对另一个位点具有抑制活性的负向相互作用;对开花时间具有上位效应的基因在转录水平上以时间和组织特异性方式受到调控，并且可能是转录调控;在大麦中获得的数据可以转移到其他重要的和遗传上更复杂的作物，如小麦。主要目标是在遗传和分子水平上对大麦开花时间的上位性效应进行功能表征。基于MAGIC群体的上位性分析提供了一个平台，用于识别从营养阶段到生殖阶段的过渡中的新基因相互作用。在小麦中验证大麦的结果将为小麦等复杂基因组中的性状提供新的证据，并显示数据在谷物物种中的可转移性。这些结果将有助于更好地了解开花启动的途径，并将为谷物育种者提供基于知识的育种计划的工具。本研究的部分目的是：通过高密度遗传图谱（50 K SNP芯片）改进单倍型模块构建，提高MAGIC群体开花时间上位性效应估计的分辨率;对所选位点在其他冬、春大麦关联组中进行估计和验证;在上位性效应位点上鉴定候选基因并在结构水平上分析等位基因变异; 相互作用基因的动力学和植物器官表达，以更好地了解开花起始上位性的分子基础;确定的上位性效应从大麦到小麦的转移和验证，作为一种重要的经济自花授粉作物。

Hypothesis on which the proposal is based on:MAGIC based populations constitute a solid basic for genetic analysis of epistatic effects and identification of genes interacting in positive direction by complementing or enhancing each other or negative direction with suppressor activity of one locus towards the other;Genes with epistatic effects to flowering time are regulated at transcription level in time and tissue specific manner and possibly reciprocally;The data obtained in barley can be transferred to other important and genetically more complex crops like wheat.The main goal is the functional characterization of epistatic effects for flowering time in barley at genetic and molecular level. MAGIC population based epistatic analysis offers a platform for identification of novel gene interactions in the transition from vegetative to reproductive phase. The validation in wheat of the results from barley will give new evidence for the trait in complex genomes like wheat and show the transferability of the data across the cereal species. The results will help for a better understanding of the pathways leading to flowering initiation and will offer the cereal breeders tools for knowledge-based breeding programs. Partial objectives of this study are:Improved haplotype block building through higher dense genetic map (50K SNP chip) resulting in increase of the resolution of estimated epistatic effects for flowering time in the MAGIC populationEstimation and validation in other winter and spring barley association panels of the selected loci; Identification of candidate genes at loci with epistatic effects and analysis of allelic variation at the structural level; Kinetic and plant organ expression of interacting genes to better understand the molecular basis of epistasis in flowering initiation;Transfer and validation of determined epistatic effects from barley to wheat as an economical important self pollinating crop.