Alternative Splicing of Duplicated Genes in Polyploid Brassica napus

多倍体是一种具有额外一组染色体的生物体，在植物中很常见，许多农作物都是多倍体。多倍体的形成通常涉及两个物种之间的杂交（杂交），然后是染色体加倍。多倍体可以导致新的形态和发育特征，更大的细胞大小，和新的基因功能和表达模式。我的研究计划的长期目标是了解多倍体对复制基因的进化、表达、剪接和功能的影响。我们研究进化上最近的多倍体植物，以及来自数百万年前发生的古老多倍体事件的基因，以确定重复基因进化的长期结果。本研究计划的目标是了解多倍体对基因表达的影响，重点关注RNA剪接（选择性剪接）在环境胁迫条件下的反应。将甘蓝型油菜多倍体与其二倍体亲本种rapa和甘蓝进行比较。压力处理将包括热、冷、旱和盐。为了检查每种应激处理对RNA表达和剪接的影响，RNA将使用高通量方法进行测序，该方法提供了整个转录本（同种异构体）的序列。这些数据将用计算方法进行分析。提出的研究将提供多倍体中复制基因之间转录异构体差异的见解，以及揭示多倍体与其二倍体亲本物种的比较。此外，在芸苔系的进化史中，一个更古老的多倍体复制的基因中的RNA剪接模式将被分析，以评估在更长期的进化时间尺度上转录异构体的变化。这项研究可能会对植物基因组学、植物分子生物学和分子进化等领域产生影响。一些重复基因在植物中起着决定重要农艺性状的作用。某些复制基因的RNA剪接模式可能与植物育种过程中所选择的性状有关。特别是，多倍体油菜（Brassica napus）对加拿大的经济和粮食供应非常重要，研究油菜RNA剪合的结果可能会导致这种作物的改良。

Polyploids, organisms with an extra set of chromosomes, are common among plants and many crop plants are polyploids. The formation of polyploids often involves hybridization (crossing) between two species followed by chromosome doubling. Polyploidy can lead to novel morphological and developmental characteristics, larger cell sizes, and new gene functions and expression patterns. The long-term goals of my research program are to understand the consequences of polyploidy on the evolution, expression, splicing, and function of duplicated genes. We study evolutionarily recent polyploid plants, as well as genes derived from ancient polyploidy events that occurred millions of years ago to determine the long-term outcomes of duplicate gene evolution. The goal of this research proposal is to understand the consequences of polyploidy on gene expression with a focus on patterns of RNA splicing (alternative splicing) in response to environmental stress conditions. Brassica napus (canola) polyploids will be compared with their diploid parental species, B. rapa and B. oleracea. Stress treatments will include heat, cold, drought, and salt. To examine the effects of each stress treatment on RNA expression and splicing, the RNA will be sequenced with a high-throughput method that provides sequences of entire transcripts (isoforms). The data will be analyzed with computational approaches. The proposed research will provide insights into differences in transcript isoforms between duplicated genes in the polyploids, as well as reveal how the polyploids compare with their diploid parental species. In addition, RNA splicing patterns in genes duplicated by a much older polyploidy during the evolutionary history of the Brassica lineage will be analyzed to assess changes in transcript isoforms on a longer-term evolutionary time scale. This research is likely to have an impact on the fields of plant genomics, plant molecular biology, and molecular evolution. Some duplicate genes play a role in specifying traits of agronomic importance in plants. Some RNA splicing patterns in duplicated genes may be involved in conferring traits selected for during plant breeding. In particular, polyploid canola (Brassica napus) is very important to Canada's economy and food supply and what is learned from studying RNA splicing in canola may lead to improvement of this crop plant.