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，光合作用生物感知并对其光环境的变化做出反应。许多蓝藻具有改变其捕光复合体的蛋白质组成的能力，以响应环境中普遍存在的光的颜色的变化。这一过程被称为补色适应(CCA)，在Fremyella diplosiphon中，对红色和绿色光照最敏感。CCA由一种光敏胆蛋白RcaE(染色适应调节因子)控制。为了增加对CCA分子基础的了解，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；以及(3)表征RcaE向其传递感知光信号的下游效应器。将采用分子遗传学和生物化学方法来实现这些目标。由于RcaE是与一种离散的生理现象密切相关的原核类光敏色素相关蛋白的少数成员之一，阐明RcaE控制生长和发育的调控基因网络有望为深入了解光合作用系统中胆蛋白调节光形态发生的操作机制提供洞察。广泛影响：除了对研究生和博士后学者的培训外，这项研究的更广泛影响将包括对本科生和来自未被充分代表的群体的学生的影响，包括女性和密歇根州立大学查尔斯·德鲁科学丰富计划的参与者。这项研究的培训部分将被设计为发展这些学生的分析和批判性思维的能力。这一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。教育的重点是在本科生生物化学调查课程中使用和评估主动学习教学法。

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.