ELF3 Regulation of Circadian Rhythm and Flowering in Arabidipsis

Meeks-Wagner 9808208早花3（ELF 3）基因已从拟南芥中克隆，并已发现与现有数据库中的基因缺乏任何相似性。 迄今为止的结果表明，ELF 3功能作为一种新的昼夜节律振荡器的关键调节器，以及花序和花分生组织身份基因的调节器。 ELF 3基因产物通过作为控制生物钟活性的感光通路的组分起作用来调节光周期性的假设将被检验。 ELF 3在调节控制花分化和花分生组织发育的遗传途径中的作用也将被研究。 具体目标是：2）通过使用内源性ELF 3调节序列和组成型的、组织特异性的，诱导型启动子系统3）确定与ELF 3基因功能相关的遗传途径，所述基因功能调节拟南芥中的花起始和分生组织身份4）鉴定与ELF 3相互作用以促进适当的昼夜节律反应和开花的基因产物，并鉴定受ELF 3功能调节的基因，其可能是下游基因或作为昼夜节律钟的自动调节组分的基因。本研究的长期目标是了解调节植物对日照长度变化的发育反应的分子机制。 像花的启动这样的反应很可能是由感光通路控制的，感光通路也会影响植物的生物钟功能。 一个分子遗传学的方法来了解光周期控制开花拟南芥将采取，集中在ELF 3基因，分离和特点，在这个实验室。 以前的研究结果表明，ELF 3代表的可能性，在高等植物的昼夜节律振荡器和发育反应的感光输入途径之间的联系。 在模式植物中光形态发生和花起始的遗传和分子基础的框架的发展将使得有可能更好地在重要植物中工程化所需的修饰。

Meeks-Wagner9808208The Early Flowering 3(ELF3) gene has been cloned from Arabidopsis thaliana and has been found to lack any similarity to genes in the available databases. Results to date suggest that ELF3 functions as a novel key regulator of the circadian oscillator, as well as a regulator of inflorescence and floral meristem identity genes. The hypothesis that the ELF3 gene product regulates photoperiodism by functioning as a component of a photosensory pathway that controls the activity of circadian clocks will be tested. The role of ELF3 in regulating the genetic pathways that control floral initiation and flower meristem development will also be investigated. The specific aims are: 1) To characterize the spatial and temporal regulation of ELF3 transcription and translation 2) To create and characterize -developmentally and for circadian responses- various transgenic lines that overexpress or ectopically express ELF3 by using the endogenous ELF3 regulatory sequences, and constitutive, tissue specific, inducible promoter systems 3) To define the genetic pathways related to ELF3 gene function that regulate floral initiation and meristem identity in Arabidopsis 4) To identify gene products that interact with ELF3 to facilitate proper circadian response and flowering and to identify genes regulated by ELF3 function which may be downstream genes or genes that are autoregulated components of the circadian clock.The long-term goal of this research is to understand the molecular mechanisms that regulate plant developmental responses to changes in daylength. Responses such as floral initiation are likely to be controlled by photosensory pathways that also impinge upon the function of the circadian clocks of plants. A molecular genetic approach to understanding the photoperiodic control of flowering in Arabidopsis will be taken, focused upon the ELF3 gene, isolated and characterized in this laboratory. Previous results suggest the possibility that ELF3 represents a link between photosensory input pathways to the circadian oscillator and developmental responses in higher plants. The development of a framework for the genetic and molecular basis of photomorphogensis and floral initiation in the model plant will make it possible to better engineer desirable modifications in commerically important plants.