Functional Genomics of Woody Perennial Flowering

花形成的诱导、起始和完成是被子植物生命周期中的关键事件。没有开花，就没有种子形成，后代就无法繁殖。在食用植物中，及时和充足的种子产量对人类和动物的营养至关重要。对人类至关重要的开花过程，已经在一年生草本植物中进行了广泛的研究，这些植物在一年内发芽、生长、开花、结籽和死亡。许多调节开花过程的基因已经在小型一年生植物拟南芥中被识别和研究，拟南芥可以作为作物的模型。然而，对多年生木本植物如树木的开花调控机制知之甚少。该项目将研究杨树属树木的开花过程，包括杨树、白杨和杨树。与一年生植物不同，树木每年都要经历营养和花卉生长的循环，这受到温度和光照剧烈季节性变化的影响。目的是发现一年生植物和多年生植物的开花调控因子之间的重要异同。为了确定拟南芥和杨树在响应环境和生理因素时花芽诱导/起始的分子基础是否存在差异，我们开展了一项研究项目。项目活动将包括植物的生理和遗传操作、基因序列的进化比较和为实现这些目标而检查表达模式。杨树已经成为树木研究的实验模型，因为整个基因组已经被测序，而且这种植物可以进行基因改造。杨树物种具有重要的经济和生态价值，该项目的研究成果将具有许多实际应用价值。这些措施包括操纵种子/果实生产、加速育种计划、增加木质生物质产量和转基因生物限制等。该项目的外联部分包括为教师举办生物技术讲习班，为参与实验室的个别研究项目征聘高中和大学少数民族学生。项目成果将通过杨树花卉基因组网站（可通过http://www.floralgenome.org/访问）和杨树基因组门户网站（http://bahama.jgi-psf.org/prod/bin/populus/home.populus.cgi）获得。

The induction, initiation and completion of flower formation are critical events in the angiosperm life cycle. Without flowering there would be no seed formation for the propagation of subsequent generations. In food plants, timely and adequate seed yields are essential for human and animal nutrition. The process of flowering, which is so vital to humankind, has been extensively studied in herbaceous annual plants that germinate, grow, flower, produce seed and die within one year. Many of the genes that regulate the flowering process have been identified and studied in the small annual plant, Arabidopsis, which serves as a model for crops. However, little is known about the mechanisms regulating flowering in woody perennial plants such as trees. This project will study the flowering process in trees in the genus Populus, which contains cottonwoods, aspens and poplars. Unlike annual plants, trees undergo cycles of vegetative and floral growth each year that are affected by dramatic seasonal changes in temperature and light. The goals is to discover the important differences and similarities among the factors that regulate flowering in annual and perennial plants. A research project has been developed to determine if the molecular basis of floral bud induction/initiation in response to environmental and physiological factors differs between Arabidopsis and Populus. Project activities will include physiological and genetic manipulations of plants, evolutionary comparisons of gene sequences and examination of the expression patterns to accomplish these objectives. Populus has become the experimental model for tree research because the entire genome has been sequenced and the plant can be genetically transformed. Populus species are economically and ecologically important and the outcomes of this project will have many practical applications. These include manipulation of seed/fruit production, acceleration of breeding programs, increased production of woody biomass, and biological confinement of transgenes, among others. Outreach components of the project range from biotechnology workshops for teachers to recruitment of high school and college minority students for individual research projects in participating laboratories.Project outcomes will be available through the Populus Floral Genome Web Site (accessible through http://www.floralgenome.org/) and the Populus Genome Portal (http://bahama.jgi-psf.org/prod/bin/populus/home.populus.cgi).