Identification and molecular characterisation of genes involved in the perennial life cycle

在驯化过程中，定向选择有利于产量高、生活周期短的植物。因此，现在大多数栽培作物是一年生的，尽管它们的野生型祖先是多年生植物。一年生作物的种植对环境有负面影响，并且仅限于具有最佳生长条件的地区。因此，新的育种努力的目标是多年生作物的发展。本项目以高山南芥为模式植物，研究其开花和多年生性状的分子调控机制。此前，A. alpina的结果是确定了调控开花和促成多年生生长习性的基因。在第一阶段，我建议筛选诱变人口的永久开花1（pep1）突变体，并寻找第二个网站的突变体，影响开花时间，并对营养发育具有多效性的影响。本研究表明，A. alpina的APETALA 2（AaAP 2）直向同源物。alpina通过春化依赖和非春化依赖途径调节开花。AP2在春化过程中的作用以前在拟南芥中没有报道。在第二阶段，我建议扩展对AaAP 2的研究，并使用转录组分析和染色质免疫沉淀来确定其靶标。在第一阶段，我还确定了三个突变体，加速开花pep1相比，并有多效性的影响花序发育。在第二阶段，我想分离和鉴定导致这些突变表型的基因。在许多温带多年生植物的花序发育的时间不同的一年生植物相比，因此，这些基因的鉴定可能会给这个过程的见解。A.高山草属是菊科的一员。因此，了解调控开花和多年生性状的分子机制可以直接应用于多年生芸苔属作物的发展，并产生有关在分歧多年生植物中调控多年生的原则的知识。

During the process of domestication directional selection favored plants with higher yield and shorter life cycle. Thus nowadays, most cultivated crops are annuals although their wild type ancestors are perennials. Cultivation of annual crops has negative impact on the environment and is limited to regions with optimal growth conditions. Thus new breeding efforts are aiming on the development of perennial crops. This project uses Arabis alpina as a model to study the molecular mechanisms that regulate flowering and perennial traits. Previously, a forward genetics approach in A. alpina resulted in the identification of genes that regulate flowering and contribute to the perennial growth habit. In the first phase I proposed to screen a mutagenised population of the perpetual flowering 1 (pep1) mutant and look for second-site mutants that affect flowering time and have pleiotropic effects on vegetative development. This study demonstrated that the A. alpina orthologue of APETALA2 (AaAP2) in A. alpina regulates flowering though a vernalisation -dependent and -independent pathway. The role of AP2 in vernalisation has not been previously reported in Arabidopsis thaliana. In the second phase I suggest to extend the study on AaAP2 and identify its targets using transcriptome profiling and Chromatin Immunoprecipitation. In the first phase I also identified three mutants that accelerate flowering compared to pep1 and have pleiotropic effects on inflorescence development. In the second phase I would like to isolate and characterise the genes responsible for these mutant phenotypes. The timing of inflorescence development in many temperate perennials differs compared to annuals and therefore identification of these genes might give insights on this process. A. alpina is a member of the Brassicaceae family. Therefore, understanding of the molecular mechanisms regulating flowering and perennial traits can be directly applied to the development of perennial Brassica crops and generate knowledge about the principles regulating perennialism in diverged perennials.