Arabidopsis as a New Experimental Platform to Investigate the Function of the Nuclear Pore Protein Tpr in SUMOylation and mRNA export.

智力上的优点。 核孔复合体（NPC）是细胞核和细胞质之间交通的看门人。NPC的结构和蛋白质含量在真核生物中是保守的。在几种真核生物中的NPC的研究表明，长卷曲螺旋Tpr蛋白在mRNA输出中具有重要作用。 Meier博士已经鉴定了拟南芥Tpr基因的三种突变体的等位基因系列，其显示三种表型的严重性的伴随增加，即早花、增加的SUMO化蛋白积累和多聚（A）+ RNA的核积累。SUMO化是蛋白质的翻译后修饰，具有多肽SUMO。 翻译后修饰是一种改变蛋白质性质的调控机制。Meier博士已经证明AtTpr和拟南芥SUMO蛋白酶在物理和遗传上相互作用。三个具体的目标将调查AtTpr在核孔的功能。分别是：1.说明AtTpr将SUMO蛋白酶锚定在核孔上并影响其生物学活性;2. 使用蛋白质组学方法纯化AtTpr复合物，以确定是否存在mRNA输出机制的组分; 3.利用tpr突变体等位基因的抑制子和增强子的遗传筛选来鉴定连接开花时间、SUMO稳态和mRNA输出的新组分。 该项目利用第一个可用的多细胞系统来研究Tpr突变体对发育的影响，可能是通过锚定核孔相关活动。 更广泛的影响。 作为该项目的一部分，数据库管理，教育和推广活动将在迈耶博士的实验室进行。拟南芥长卷曲螺旋蛋白ARABI-COIL的可搜索数据库可广泛用于TAIR列出的科学界，并将持续管理。在过去的三年中，一个新的生物信息学模块的植物分子生物学课程已经开发出来，PI参加了当地的功能基因组学夏季课程，目标是来自俄亥俄州大学的学生和教师。这些或类似活动将在拟议供资期内继续进行。PI不断为公众提供植物生物技术在线课程。本科生、研究生和博士后将接受培训，并在国家和国际会议、同行评审出版物和评论文章中展示他们的数据。

Intellectual merit. The nuclear pore complex (NPC) is the gatekeeper for traffic between the nucleus and the cytoplasm of the cell. The NPC structure and protein content is conserved among eukaryotes. Studies of the NPC in several eukaryotic organisms suggest that the long coiled-coil Tpr protein has an important role in mRNA export. Dr. Meier has identified an allelic series of three mutants of the Arabidopsis Tpr gene which show a concomitant increase in severity of three phenotypes i.e. early flowering, Increased SUMOylated protein accumulation, and nuclear accumulation of poly(A)+ RNA. SUMOylation is a post-translational modification of proteins with the polypeptide SUMO. Post-translation modification is a regulatory mechanism that alters the properties of proteins. Dr. Meier has shown that AtTpr and an Arabidopsis SUMO protease interact physically and genetically. Three specific aims will investigate the function of AtTpr at the nuclear pore. They are:1. To show that AtTpr anchors the SUMO protease to the nuclear pore and influences its biological activity;2. To use a proteomics approach to purify AtTpr complexes to determine whether components of the mRNA export machinery are present; 3. To use a genetic screen for suppressors and enhancers of a tpr mutant allele to identify new components connecting flowering time, SUMO homeostasis and mRNA export. This project utilizes the first available multicellular system to study the effects of Tpr mutants on development, likely through the anchoring of nuclear pore-associated activities. Broader Impact. As part of this project, database management, education, and outreach activities will be performed in Dr. Meyer's laboratory. A searchable database for Arabidopsis long coiled-coil proteins ARABI-COIL is widely available to the scientific community listed at TAIR and will be continuously curated. During the past three years, a new bioinformatics module for a plant molecular biology course has been developed and the PI has participated in a local Functional Genomics Summer Course targeting students and faculty from Ohio colleges. These or similar activities will continue in the proposed funding period. The PI is continuously offering an online course for the general public on Plant Biotechnology. Undergraduate students, graduate students and postdocs will be trained and will present their data at national and international meetings, in peer-reviewed publications and in review articles.