Lateral root development in Arabidopsis seedlings and its regulation by light

最近，我们发现幼苗初生根的伸长生长受光合同化物的有效性控制。此外，我们可以提供证据表明，光控制侧根的发展。侧根从主根的周鞘细胞重新出现，这是一个由生长素信号介导的过程。本研究的目的是阐明模式系统拟南芥侧根原基和生长的光调控。考虑到到目前为止有限的知识，光控制这些过程中，我们想集中在以下基本的和开放的问题：它是不知道到目前为止，哪些光感受器和相应的信号成分参与控制侧根的发展。在这第一个复杂的分析的背景下，我们还想解决的问题，幼苗的器官负责入射光信息的感知。第二个关键方面将针对的问题，如果定位侧根的主根轴是由内源性的蓝图介导或光刺激控制。这一分析意味着明显的区别侧根原基的原基和这些结构的生长。 由于激素生长素在侧根发育过程中的重要作用，我们最终想解决的问题是光和生长素信号的分子水平整合是如何发生的。研究计划的这些关键问题将通过光生物学、细胞生物学和遗传技术来执行。

Recently, we could show that elongation growth of the young primary root in seedlings is controlled by the availability of photosynthetic assimilates. In addition, we could provide evidence that light controls lateral root development. Lateral roots emerge de novo from pericycle cells of the main root, a process which is mediated by auxin signaling. The aim of this research proposal is to elucidate the photo regulation of anlage and outgrowth of lateral roots in the model system Arabidopsis thaliana. Considering the so far limited knowledge about photo control of these processes we want to focus on the following essential and open questions.It is not known so far which photoreceptors and corresponding signaling components are involved in control of lateral root development. In the context of this first complex of analysis we additionally want to address the question which organs of the seedling are responsible for perception of the incident light information. The second key aspect will be directed to the question if positioning of lateral roots on the main root axis is mediated by an endogenous blueprint or controlled by light stimuli. This analysis implies clear distinction between anlage of lateral root primordia on the one and outgrowth of these structures on the other hand. Because of the essential contribution of the hormone auxin during the process of lateral root development we finally want to address the question how and on which molecular level integration of light and auxin signaling takes place. These key questions of the research proposal will be executed by means of photo biological, cell biological and genetic technologies.