Role of an LRR Receptor-Like Kinase in Root Epidermal Patterning

0316312 Schiefelbein在发育过程中，所有多细胞生物都会产生不同的细胞类型，并以适当的模式组织这些细胞类型。 该项目的研究旨在揭示生物在发育过程中产生和形成不同细胞类型的基因和分子机制。 本计画利用一个简单的模型系统来研究细胞类型特化：开花植物拟南芥根表皮的形成。 拟南芥根表皮是例外，因为它的两种细胞类型是在一个可预测的位置依赖模式产生。 此外，根表皮随着根的生长而连续形成，因此可以在一个时间内检查所有发育阶段。 最后，缺乏任何一种根表皮细胞类型的植物都是可行的，这使得能够进行复杂的分子遗传操作。 最近的研究表明，拟南芥根表皮细胞类型的特化依赖于一个复杂的转录调控网络。 在表皮发育过程中产生几种转录因子，这些转录因子参与正反馈和负反馈回路，根据它们的位置，维持或抑制它们在特定细胞中的表达。 该项目的研究旨在解决该系统中的一个重要问题：是什么导致一个位置的细胞以不同于另一个位置的细胞的方式表达这些基因？ 最近，一个受体样蛋白，SCRAMBLED（SCM），已被确定，影响的位置依赖性模式的细胞类型。 该项目旨在研究这种受体样SCM蛋白的特定作用。 主要目标是：（1）确定SCM mRNA和蛋白在发育根中的位置，（2）分析SCM受体功能和转录调控网络之间的关系，（3）表征与SCM蛋白相似的其他受体样蛋白，以及（4）鉴定SCM信号传导途径的新遗传组分。 这些线的调查，预计将提供深入了解的分子基础上的行动，在发展过程中的位置线索。 更一般地说，这将导致更好地理解在多细胞生物中产生和调节细胞多样性的机制。

0316312Schiefelbein During their development, all multicellular organisms generate diverse cell types and organize these cell types in appropriate patterns. The research in this project is designed to uncover the genes and the molecular mechanisms used by living things to produce and to pattern distinct cell types during development. This project uses a simple model system to study cell-type specification: the formation of the root epidermis in the flowering plant Arabidopsis thaliana. The Arabidopsis root epidermis is exceptional because its two cell types are produced in a predictable position-dependent pattern. Furthermore, the root epidermis is formed continuously as the root grows, so all stages of development can be examined at a single time. Finally, plants that lack either root epidermal cell type are viable, which enables sophisticated molecular genetic manipulations to be conducted. Recent studies suggest that cell type specification in the Arabidopsis root epidermis relies on a complex transcriptional regulatory network. Several transcription factors are produced during epidermis development, and these are involved in positive and negative feedback loops that maintain or inhibit their expression in particular cells, depending on their position. The research in this project is intended to address an important question in this system: What causes cells in one position to express these genes in a different way than cells in another position? Recently, a receptor-like protein, SCRAMBLED (SCM), has been identified that influences the position-dependent pattern of cell types. This project is designed to examine the specific role of this receptor-like SCM protein. The major aims are: (1) to define the location of the SCM mRNA and protein in the developing root, (2) to analyze the relationship between the SCM receptor function and the transcriptional regulatory network, (3) to characterize other receptor-like proteins that are similar to the SCM protein, and (4) to identify new genetic components of the SCM signaling pathway. These lines of investigation are expected to provide insights into the molecular basis for the action of positional cues during development. More generally, this will lead to a better understanding of the mechanisms employed to generate and regulate cellular diversity in multicellular organisms.