植物向光素phot1调控的内吞信号支路的研究

对植物感光机制的深入研究不仅具有较高理论价值，还在农林业应用上具有潜在价值。我们发现，植物膜受体向光素phot1介导的内膜囊泡效率和蓝光信号强度相关。 并且，phot1及其关键的信号转导蛋白NPH3还能通过影响PIN2的内膜循环来调控拟南芥根尖的生长素极性运输。根据这些前期结果，我们将借鉴动物细胞生物学上的信号小体（Signalsome）的聚集和控制内吞囊泡形成与循环的理论，通过应用新兴的蛋白质标记、示踪和单分子定量分析技术，在生理条件下实时观测并定量研究蓝光信号强度和phot1/NPH3的聚集、内吞过程。此外，还将利用在活细胞中实时动态和定量观测荧光标记的蛋白分子间互作模式的FRET与FCCS技术，研究phot1，NPH3与内膜运输的关键蛋白ARF1之间的互作模式，为探索植物细胞膜在响应环境信号的调控作用奠定理论基础。

In-depth study of plant light-sensing mechanism not only has a high theoretical value, but also a potential value in the application field of agriculture and forestry. In previous studies, we found that the plant membrane photoreceptors, phot1, mediated a blue light-dependent vesicular endocytosis, which reflects the signal intensity and duration from blue light. Moreover, the phot1 and its crucial signal transducer, NPH3, can also adjust the root polar auxin transport by regulating the PIN2 endosomal recycling. Based on these results, we will draw lessons from the new theory of signalsome-mediated endocytosis from the animal cell biology. We will quantitatively analyze the aggregation and clustering of phot1 and NPH3 through application of advanced protein marking, tracing and single-molecule analysing technology, revealing the relationship between these dynamic behaviours and blue light signal intensities. Furthermore, we will also use the FRET and FCCS technologies to observe and analyze the protein interaction behaviours between phot1, NPH3 and the small G-protein, ARF1 in living cells. All together, this study will establish a new mode of investigation to analyze the role of plasma membrane in the regulation of different environmental signals.