Arabidopsis 2010: Determination of Biological Functions of the NPH3/RPT2 Family

拟南芥 2010：NPH3/RPT2 家族生物学功能的测定

• 批准号: 0114992
• 负责人: Emmanuel Liscum
• 金额: $ 90万
• 依托单位: University of Missouri-Columbia
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-09-01 至 2006-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0114992&HistoricalAwards=false
• 关键词: Arabidopsis; 2010; Determination; Biological; Functions

Because of their sessile nature, plants have evolved a wide range of strategies to respond to changes in their environment. For a number of these responses plants have co-opted (or co-evolved) systems that are shared with other taxa. However, many of the environmental (both biotic and abiotic) response systems plants utilize are apparently specific to plants and are often comprised of novel molecular components. With the recent completion of the Arabidopsis genome sequencing project we are now in a unique position to ask fundamental questions about the functions of these latter set of regulatory proteins in plants. Of the ~11,000 protein families formed by the 25,498 predicted genes of Arabidopsis, only ~150 families appear to be plant-specific. One of these plant-specific families is the NPH3/RPT2 family. This family, which is comprised of 32 novel proteins (for more information about these proteins/genes, including GenBank accession numbers, see http://www.biosci.missouri.edu/liscum/nph3-rpt2figs.html), was first identified with the cloning of NPH3 (NONPHOTOTROPIC HYPOCOTYL 3) and RPT2 (ROOT PHOTOTROPISM 2) - genes identified in screens for mutants with altered phototropic responses. NPH3 and RPT2 function in early phototropic signaling and appear to act as modular scaffold proteins to recruit or activate enzymatic components of the transduction chains, including the respective photoreceptors themselves, mediating phototropic responses. Given the high degree of similarity in primary sequence and secondary structure between all members of the NPH3/RPT2 family it seems appropriate to hypothesize that these plant-specific proteins may act as scaffolds for sensor-containing signaling complexes utilized in a variety of abiotic and/or biotic responses. The major goals proposed for this project are to determine mRNA and protein expression patterns, and biological functions for each member of the NPH3/RPT2 family. The expression studies are proposed as a means of developing logical and focused analyses of loss- and gain-of-function mutants. In such a way we expect to be able to determine what biological processes require the function of each member of the NPH3/RPT2 family. All project data will be publicly available through a project database (http://www.biosci.missouri.edu/liscum/NPH3-RPT2family.html), as well as The Arabidopsis Information Resource (TAIR) (http://www.arabidopsis.org/home.html). Given the plant-specific and novel nature of the NPH3/RPT2 family, it is likely that elucidation of biological functions for the family will represent an important step in understanding fundamental aspects of plant growth and development.

由于它们的固着性，植物已经进化出了广泛的策略来应对环境的变化。 对于许多这些反应，植物具有与其他类群共享的增选（或共同进化）系统。 然而，植物利用的许多环境（生物和非生物）响应系统显然是植物特有的，并且通常由新的分子组分组成。 随着最近完成的拟南芥基因组测序计划，我们现在在一个独特的位置，问这些后一组调节蛋白在植物中的功能的基本问题。 在拟南芥的25，498个预测基因形成的约11，000个蛋白质家族中，只有约150个家族似乎是植物特异性的。 这些植物特异性家族之一是NPH 3/RPT 2家族。 该家族由32种新蛋白质组成（关于这些蛋白质/基因的更多信息，包括GenBank登录号，参见http：//www.biosci.missouri.edu/liscum/nph3-rpt2figs.html），首先通过克隆NPH 3（非向光性下胚轴3）和RPT 2（根向光性2）-在筛选具有改变的向光性反应的突变体中鉴定的基因-鉴定。 NPH 3和RPT 2在早期向光性信号传导中起作用，并且似乎充当模块支架蛋白以募集或激活转导链的酶组分，包括各自的光感受器本身，介导向光性反应。考虑到NPH 3/RPT 2家族所有成员之间的一级序列和二级结构的高度相似性，似乎可以适当地假设这些植物特异性蛋白质可以充当用于各种非生物和/或生物反应的含传感器的信号传导复合物的支架。 该项目的主要目标是确定NPH 3/RPT 2家族每个成员的mRNA和蛋白质表达模式以及生物学功能。 表达的研究提出了作为一种手段，发展逻辑和重点分析的损失和获得的功能突变体。 通过这种方式，我们希望能够确定哪些生物过程需要NPH 3/RPT 2家族每个成员的功能。 所有项目数据都将通过项目数据库（http：//www.biosci.missouri.edu/liscum/NPH3-RPT2family.html）以及拟南芥信息资源（TAIR）（http：//www.arabidopsis.org/home.html）公开提供。 鉴于NPH 3/RPT 2家族的植物特异性和新颖性，很可能阐明该家族的生物学功能将代表理解植物生长和发育的基本方面的重要一步。