D-raf in Drosophila Signal Transduction

该项目的长期目标是确定D-raf介导的信号转导在果蝇模式的建立和完善中的作用。该项目的具体目的是：1)验证D-raf作为丝氨酸/苏氨酸激酶的激活依赖于诱导“末端”信号转导通路的模型，2)表征D-raf蛋白在发育过程中的分布模式，3)鉴定编码D-raf介导的信号转导通路其他成员的基因。由于D-raf是果蝇中Raf-1原癌基因的同源基因，因此对其发育作用的表征及其调控机制的确定将为理解高等生物中的信号转导提供线索。本提案中设计的实验旨在解决以下问题。D-raf蛋白是否表现出丝氨酸/苏氨酸激酶活性，正如其与Raf-1的同源性所预测的那样？D-raf的磷酸化状态与其作为丝氨酸/苏氨酸激酶的能力之间是否存在关系？D-raf蛋白存在于细胞的什么位置，处于什么发育阶段？哪些其他类型的基因产物在D-raf介导的信号转导途径中起作用？这些问题将回答使用细胞生物学，遗传学和分子手段。

The long term objective of this project is to define the role of D-raf mediated signal transduction in the establishment and elaboration of pattern in Drosophila melanogaster. The specific aims of this project are as follows: 1) to test the model that activation of D-raf as a serine/threonine kinase depends upon induction of the "terminal" signal transduction pathway, 2) to characterize the pattern of D-raf protein distribution in development, and 3) to identify genes encoding other members of D-raf mediated signal transduction pathways. Since D-raf is the Drosophila homologue of the Raf-1 proto-oncogene, the characterization of its developmental role and the determination of its mechanisms(s) of regulation will provide clues toward understanding signal transduction in higher organisms. Experiments have been designed in this proposal to address the following questions. Does the D-raf protein display a serine/threonine kinase activity as predicted by its homology with Raf-1? Is there a relationship between the phosphorylation state of D-raf and its ability to act as a serine/threonine kinase? Where in the cell, and at what developmental stages is the D-raf protein present? What other types of gene products act in D-raf mediated signal transduction pathways? These questions will be answered using cell biological, genetic and molecular means.