Genetic, molecular, and biochemical analysis of RNA splicing factors critical for maize endosperm development

该项目将研究植物如何处理RNA以影响玉米籽粒的组成和品质。所有生物都通过将DNA转录成RNA来表达基因，大多数RNA分子被翻译成蛋白质。在植物、动物和真菌中，编码蛋白质的基因通常具有由表达蛋白质所需的外显子和需要通过RNA剪接因子去除的内含子组成的模块结构。该项目将研究四种RNA剪接因子在去除玉米籽粒发育所需基因内含子中的作用。该研究将整合遗传，分子，基因组和生物化学方法，以确定受这些剪接因子影响的基因的功能网络，并可能识别可用于改善作物种子结实或籽粒填充的基因。该项目将通过旨在帮助学生发展成为专业科学家的多种活动，对研究生和本科生进行生物研究培训。前体mRNA的剪接对于将基因表达为表型至关重要。然而，植物RNA剪接因子影响剪接位点选择的分子机制以及选择性剪接如何影响植物表型在很大程度上是未知的。关于单个剪接因子的目标内含子的知识存在显着差距。目前尚不清楚单个剪接因子如何影响剪接决定以控制蛋白质组，并最终控制植物的表型。该项目将集中在剪接因子与强有力的证据功能的重要性，在玉米种子的发展。将在导致种子缺陷的剪接因子突变体中鉴定种子发育所需的RNA剪接事件。反向遗传学分析将确定已知在种子中表达的植物特异性推定剪接SR蛋白的作用。将鉴定对玉米胚乳至关重要的两种RNA剪接因子的细胞类型特异性和直接靶标。整合目标的数据将阐明单个RNA剪接因子影响基因表达以区分胚乳细胞类型并最终影响多细胞表型的机制。由于种子是玉米作物的主要产品，因此了解种子发育中的RNA剪接将促进基础分子生物学的发展，并为未来的作物改良确定途径和蛋白质。该奖项由分子和细胞生物科学部的遗传机制计划和综合有机体系统部的植物基因组研究计划共同资助，两者都在生物科学理事会。

This project will investigate how plants process RNA to influence maize grain composition and quality. All organisms express genes by transcribing their DNA into RNA, with most RNA molecules getting translated into protein. In plants, animals, and fungi, genes that code for proteins typically have a modular structure made up of exons, which are needed to express a protein, and introns, which need to be removed by RNA splicing factors. This project will examine the role of four RNA splicing factors in removing introns from genes needed to develop a maize kernel. The research will integrate genetic, molecular, genomic, and biochemical approaches to define functional networks of genes influenced by these splicing factors and may identify genes that could be used to improve seed set or grain-fill in crop plants. The project will train graduate and undergraduate students in biological research through multiple activities aimed at helping the students to develop into professional scientists. Splicing of pre-mRNA is critical to expressing genes as phenotypes. However, the molecular mechanisms by which plant RNA splicing factors influence splice site selection and how alternative splicing influences plant phenotypes are largely unknown. There are significant gaps in knowledge about the target introns for individual splicing factors. It is not known how individual splicing factors influence splicing decisions to control the proteome and, ultimately, the phenotype of the plant. This project will focus on splicing factors with strong evidence for functional importance in maize seed development. RNA splicing events required for seed development will be identified in splicing factor mutants that cause seed defects. Reverse genetics analysis will determine the roles of a plant-specific putative splicing SR protein known to be expressed in seeds. Cell-type specific and direct targets of two RNA splicing factors critical to the maize endosperm will be identified. Integrating the data from the aims will elucidate mechanisms by which individual RNA splicing factors influence gene expression to differentiate endosperm cell types and ultimately influence multicellular phenotypes. Because seeds are the primary product of maize crops, understanding RNA splicing in seed development will both advance fundamental molecular biology and identify pathways and proteins for future crop improvement. This award is co-funded by the Genetic Mechanisms Program in the Division of Molecular and Cellular Biosciences and by the Plant Genome Research Program in the Division of Integrative Organismal Systems, both in the Directorate for Biological Sciences.