Regulation of the actin cytoskeleton in the amoeba Dictyostelium discoideum by kinases and formin-dependent activities

本研究项目的重点是调查（一）在信号转导的肌动蛋白细胞骨架的激酶介导的监管原则，和（ii）在细胞因子依赖的活动选择formin。这些研究的模式生物是社会性阿米巴Dictyosteelium discoideum。(i)已知Ste20样激酶参与细胞骨架调节。我们已经分离出几个敲除突变体，其异常表型将被研究。我们在工作计划中还包括了一种非常规激酶的特性，它可能是一种D。来自多头绒泡菌的肌动蛋白激酶的盘状同源物。(ii)我们最近的研究结果对actin聚合和丝状伪足的形成的调节作用的actin dDia2的进一步研究的基础上，额外的actin活性在D。盘状突该工作计划包括产生单一和多个敲除突变体，选定的生物化学表征的结构域，并在野生型细胞和突变体的GFP标记的formin的分析。特别令人感兴趣的是D. discoideum formins ForA和dDiaS.

Focus of this research project is the investigation (i) of regulatory principles during signal transduction to the actin cytoskeleton as mediated by kinases, and (ii) of selected formins during cytoskeleton-dependent activities. The model organism for these studies is the social amoeba Dictyostelium discoideum. (i) Ste20-like kinases are known to be involved in cytoskeletal regulation. We isolated already several knockout mutants whose aberrant phenotypes will be studied. We included in the work programme also the characterization of an unconventional kinase which might be a D. discoideum homologue of the actin-fragmin kinase from Physarum polycephalum. (ii) Our recent results on the role of the formin dDia2 for regulation of actin polymerization and formation of filopodia are the basis for further studies on additional formin activities in D. discoideum. The work programme includes the generation of single and multiple knockout mutants, the biochemical characterization of selected formin domains, and the analysis of GFP-tagged formins in wild type cells and mutants. Of special interest are the putative lipid-binding domains of D. discoideum formins ForA and dDiaS.