Proteins Altered in Maize Hybrids Exhibiting Different Levels of Heterosis

主要研究者：凯瑟琳·牛顿（密苏里州，哥伦比亚大学）CoPI：布莱恩·穆尼（密苏里州，哥伦比亚大学）同一物种内近交品种的杂交通常会产生更有活力和更高产的杂交后代。植物育种家利用杂种优势（杂种优势）现象来提高世界粮食产量，但其潜在机制仍不明确。 尽管一些研究表明许多基因的表达在杂种中发生了变化，但对杂种优势反应最重要的变化尚未确定。 杂种优势在玉米中特别普遍。 来自不同自交玉米系之间杂交的后代可以在观察到的活力程度上变化。 为了提高活力和产量，必须优化光合作用和呼吸作用的生物能量过程。因此，线粒体呼吸在杂种优势中起重要作用的假说。 本计画将研究表现出低、中、高杂种优势的玉米杂交种，以鉴定其数量随杂种优势大小而改变的特定蛋白质。基于蛋白质组学技术的定量实验将鉴定在不同杂交体中改变的蛋白质靶点。 双向凝胶电泳和液相色谱-质谱联用将用于鉴定和定量蛋白质。 预期的结果将是发现的分子和机制，杂种优势的基础，以及鉴定有效的蛋白质标记的杂种优势。 该研究的最终影响与作物改良有关，希望所确定的蛋白质将成为提高作物生产力的具体目标。成功地识别目标蛋白质和生物能量过程，不断增加中，高水平的杂种优势，将提供重要的线索，作为潜在的分子和生化解释的现象。 该项目的所有结果都将在密苏里州大学的专门网站和NCBI-peptidome（http：//www.ncbi.nlm.nih.gov/projects/peptidome/）上公开。 此外，该项目将在多个层面上提供研究和教育的整合。 将提供博士后助理和多名本科生的培训和指导。 将为本科生开设植物基因组学的“顶点”课程。 教育推广将包括对密苏里州高中教师和学生的指导。 与公众沟通有关植物基因组学和蛋白质组学的问题，包括杂种优势的主题，将发生在两个地点：流行的“星期六早晨科学”系列讲座在大学举行，并在“科学咖啡馆”校外讨论。

PI: Kathleen J. Newton (University of Missouri, Columbia)CoPI: Brian P. Mooney (University of Missouri, Columbia)Cross-breeding of inbred varieties within a species often leads to more vigorous and higher-yielding hybrid offspring. The phenomenon of hybrid vigor (heterosis) has been harnessed by plant breeders to improve world food production, but the underlying mechanism is still undefined. Despite several investigations showing that expression of many genes change in hybrids, the changes that are most important for the heterotic response have not yet been identified. Heterosis is especially prevalent in corn (maize). Progeny from crosses between different inbred maize lines can vary in the extent of vigor observed. To increase vigor and yield, the bioenergetic processes of photosynthesis and respiration must be optimized. Therefore, the hypothesis is that mitochondrial respiration plays an important role in heterosis. This project will examine maize hybrids exhibiting low, medium, and high heterosis to identify specific proteins whose amounts are altered with the magnitude of heterosis. Quantitative experiments based on proteomics techniques will identify the protein targets that are changed in the different hybrids. Two-dimensional gel electrophoresis and liquid chromatography-coupled mass spectrometry will be used to identify and quantify the proteins. The expected outcome will be discovery of the molecules and machinery that underlie heterosis, as well as identification of validated protein markers for heterosis. The ultimate impact of the research is related to crop improvement and it is hoped that the proteins identified will become specific targets for improving the productivity of crop plants. Successful identification of target proteins and bioenergetic processes that are consistently increased in moderate and high level heterotic hybrids will provide major clues as to the underlying molecular and biochemical explanations for the phenomenon. All the results from the project will become publicly available on a dedicated University of Missouri website and NCBI-peptidome (http://www.ncbi.nlm.nih.gov/projects/peptidome/). Additionally, this project will provide integration of research and education at several levels. Training and mentoring of a postdoctoral associate and multiple undergraduates will be provided. A "capstone" course in plant genomics will be developed for undergraduates. Educational outreach will include instruction for high school teachers and students in Missouri. Communication with the general public about issues in plant genomics and proteomics, including the topic of heterosis, will occur in two venues: the popular "Saturday Morning Science" lecture series held at the University and in "science café" discussions off-campus.