Genetic and Molecular Analysis of the Regulation of Tropic Growth in Arabidopsis thaliana

拟南芥热带生长调控的遗传和分子分析

• 批准号: 9723124
• 负责人: Emmanuel Liscum
• 金额: $ 33万
• 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: 1997
• 资助国家: 美国
• 起止时间: 1997-09-01 至 2000-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9723124&HistoricalAwards=false
• 关键词: Genetic; Molecular; Analysis; Regulation; Tropic

9723124 Liscum Higher plant are dependent upon light not only as an energy source to drive carbon fixation, but also as a modulator of growth and development throughout their life cycle. Multiple wavelength regions of the electromagnetic spectrum can be utilized as regulatory cues of various developmental and morphological (photomorphogenic) responses through the action of several photoreceptor systems and associated signal transduction cascades. However, in most cases very little is known about the molecular basis for these response pathways. Our long-term objective is to elucidate the cellular and components of a plant light environment. Towards that end we have been using Arabidopsis thaliana (L.) Heynh, as a model system to investigate genetic and molecular basis of the phototropic response, or the differential growth response of various plant organs in response to directional light cues, and have identified mutants at several loci of that affect this response. Mutants in the nph4 (non-phototropic hypocotyl 4) allele series affect not only phototropism but also gravitropism and thigmotropism suggesting that NPH4 protein may be involved in the regulation og differential growth. We propose to: (a) Characterize a variety of physiological and developmental properties that require changes in growth for phenotypic expression (e.g., tropisms, light-dependent hypocotyl growth inhibition, inflorescence bolting) of the nph4 mutants in single mutant backgrounds, as well as in double and multiple mutant combinations with other phototropic and photomorphogenic mutants. (b) Clone and characterize the NPH4 gene. (c) Initiate studies to determine the biochemical function(s) of the NPH4 protein. (d) Use a variety of genetic screens (mutational, as well as biochemical) to identify additional components required for phototropism. (e) Use the photobiological characters elucidated from mutant analyses in our ongoing project to generate a genetic hierarchy for the regulation of phototropism. The rese arch proposed here should provide a wealth of information about a subset of the components of the phototropic signal-response system that are also necessary for additional tropic responses of higher plants. In addition, these studies may provide important insights into the mechanisms of how plant achieve and regulate differential growth.

9723124李斯特菌高等植物不仅依赖光作为驱动碳固定的能量来源，而且在其整个生命周期中作为生长和发育的调节剂。 电磁波谱的多个波长区域可以通过几个感光系统和相关的信号转导级联的作用用作各种发育和形态（光形态发生）反应的调节线索。 然而，在大多数情况下，对这些反应途径的分子基础知之甚少。我们的长期目标是阐明植物光环境的细胞和组成部分。 为此，我们一直在使用拟南芥（L.）Heynh作为研究向光性反应的遗传和分子基础的模型系统，或各种植物器官响应于定向光线索的差异生长反应，并且已经鉴定了影响这种反应的几个位点的突变体。 nph 4（non-phototropic hypocotyl 4）等位基因系列的突变体不仅影响向光性，而且影响向重力性和向触性，提示NPH 4蛋白可能参与了分化生长的调控。 我们建议：（a）表征需要生长变化以进行表型表达的多种生理和发育特性（例如，向性、光依赖性下胚轴生长抑制、花序抽薹）的特性。(b)NPH 4基因的克隆和鉴定。 (c)启动研究以确定NPH 4蛋白的生化功能。(d)使用各种遗传筛选（突变和生物化学）来鉴定向光性所需的其他成分。(e)利用我们正在进行的项目中的突变体分析阐明的光生物学特性，产生一个遗传层次的调节向光性。 这里提出的研究应该提供了大量的信息的一个子集的向光信号响应系统的组件，也是必要的高等植物的附加热带反应。 此外，这些研究可能会提供重要的见解植物如何实现和调节差异生长的机制。