CAREER: Molecular Genetic and Biochemical Analysis of Biliprotein-Regulated Photomorphogenesis in Cyanobacteria

为了最大限度地促进生长和发育，光合生物感知并响应其光环境的变化。许多蓝藻具有改变其光收集复合物的蛋白质组成的能力，以响应其环境中普遍颜色的光的变化。这一过程被称为互补色适应（CCA），在双虹吸freremyella diplosiphon中，对红色和绿色照明最敏感。CCA受一种光感胆道蛋白RcaE（颜色适应调节剂）控制。为了增加对CCA分子基础的认识，本项目的目标是：(1)研究RcaE的生物合成；(2)阐明RcaE感知红光和绿光的分子机制；(3)表征RcaE向其传输感知光信号的下游效应器。分子遗传学和生物化学方法将被用来实现这些目标。由于RcaE是与离散生理现象密切相关的光光色素相关蛋白的少数原核成员之一，因此阐明控制光响应生长和发育的RcaE调控基因网络有望为深入了解光合系统中胆囊蛋白调控的光形态发生的运作机制提供帮助。更广泛的影响：除了培养研究生和博士后学者外，该研究的更广泛影响将包括对本科科学专业学生和来自代表性不足群体的学生的影响，包括女性和密歇根州立大学查尔斯·德鲁科学充实计划的参与者。研究的训练部分将被设计，部分是为了培养这些学生分析性和批判性思考的能力。这个职业发展计划还包括利用教学方法来提高学生的批判性思维能力、科学素养和技术熟练程度。教学重点包括在本科生物化学概论课程中主动学习教学法的使用和评价。

In order to maximize growth and development, photosynthetic organisms sense and respond to changes in their photoenvironment. Many cyanobacteria possess the ability to alter the protein composition of their light-harvesting complexes in response to changes in the prevalent colors of light in their environment. This process is termed complementary chromatic adaptation (CCA) and, in Fremyella diplosiphon, is most responsive to red and green illumination. CCA is controlled by a photosensory biliprotein, RcaE (regulator of chromatic adaptation). To increase knowledge about the molecular basis of CCA, the goals of this project are: (1) to investigate the biosynthesis of RcaE; (2) to elucidate the molecular mechanism by which RcaE perceives red and green light; and (3) to characterize the downstream effectors to which RcaE transmits the perceived light signal. Molecular genetic and biochemical approaches will be employed to accomplish these goals. As RcaE is one of only a few members of the prokaryotic class of phytochrome-related proteins closely linked to a discrete physiological phenomenon, elucidation of the RcaE regulatory gene network that controls growth and development in response to light is expected to provide insight into the mechanisms of operation of biliprotein-regulated photomorphogenesis in photosynthetic systems.Broader Impacts:In addition to the training of graduate students and postdoctoral scholars, broader impacts of the research will include an influence on undergraduate science majors and students from underrepresented groups, including women and participants in the Charles Drew Science Enrichment Program at Michigan State University. A training component of the research will be designed, in part, to develop the ability of these students to think analytically and critically. This career development plan also includes the utilization of instructional methods that enhance students' critical thinking skills, scientific literacy, and technical proficiency. The educational focus incorporates the use and evaluation of active learning pedagogies in an undergraduate biochemistry survey course.