Genetic, Genomic, and Biochemical Approaches to Elucidate Control of Sulfur Deprivation Responses

硫是蛋白质、脂质和一些关键代谢物中的必需元素。这项研究继续探索衣原体硫剥夺反应的监管方面。调节突变体异常硫剥夺反应和抑制菌株的特点，以帮助识别信号传导因子之间的相互作用。野生型和各种突变株将查询与全基因组的方法，用于检查营养丰富和硫饥饿条件下的转录组，使用微阵列和Solexa测序技术。集中智力和技术的努力将被导向建立更多的生物化学之间的联系确定的监管机构。多种蛋白质-蛋白质相互作用测定，包括酵母双杂交系统，分裂泛素和分裂GFP系统和经典的免疫共沉淀测定将促进这些研究，提供强大的洞察力的调节电路，控制光合生物的营养限制反应。最后，将进行分析，以帮助理解最近发现的两个层次的硫剥夺反应;一个是蛋白质合成无关，而另一个是蛋白质合成依赖。从更广泛的意义上说，拟议的工作将有助于解开与光合细胞科普剥夺条件所需的调节机制相关的一些复杂性，并最终帮助我们了解我们饮食中硫化合物和全球天气模式的影响;一些硫化合物强烈影响食物的质量和营养价值，而另一些则对地球气候产生深远影响。该项目将培训一名博士后学生，并将与查尔斯豪瑟博士及其在圣爱德华大学的本科生合作，他们将参加夏季交流和微阵列结果分析。圣爱德华大学是一所少数民族服务机构。

Sulfur is an essential element in proteins, lipids, and some critical metabolites. The work proposed in this grant continues an exploration of the regulatory aspects of sulfur deprivation responses in the alga Chlamydomonas. Regulatory mutants aberrant for sulfur-deprivation responses and suppressor strains will be characterized to help identify interactions among signaling factors. Wild-type and various mutant strains will be queried with genome-wide methods for examining the transcriptome under nutrient-replete and sulfur-starvation conditions, using both microarray and Solexa sequencing technologies. Focused intellectual and technical efforts will be directed toward establishing more biochemical links between identified regulators. A diversity of protein-protein interaction assays, including the yeast two-hybrid system, the split ubiquitin and split GFP systems and the classical co-immunoprecipitation assays will facilitate these studies, providing strong insights into the regulatory circuits that control nutrient limitation responses in photosynthetic organisms. Finally, analyses will be performed to help understand the two tiers of the sulfur-deprivation response that have recently been discovered; one is protein synthesis-independent while the other is protein synthesis-dependent. In a broader sense, the proposed work will help untangle some of the complexities associated with the regulatory machinery that is required for photosynthetic cells to cope with deprivation conditions and ultimately help us understand the impact of sulfur compounds in our diets and on global weather patterns; some sulfur compounds strongly influence the quality and nutritional value of food while others have profound effects on the climate of the Earth. The project will train a post doctoral student and will involve collaboration with Dr. Charles Hauser and his undergraduate students at St. Edward's University, who will participate in summer exchange and in the analysis of microarray results. St. Edward's University is a minority serving institution.