NSF Postdoctoral Fellowship in Biology: Investigating the spatiotemporal coordination of cell and chloroplast division

Clark-Cotton, Manuella R, Durham NC

Investigators

Abstract

This action funds an NSF Postdoctoral Research Fellowship in Biology for FY 2022, Broadening Participation of Groups Underrepresented in Biology. The Fellowship supports a research and training plan for the Fellow that will increase the participation of groups underrepresented in biology. In this project, the Fellow will investigate intracellular communication and the coordination of key cellular processes in photosynthetic organisms. During photosynthesis, land plants and algae use specialized cell structures called chloroplasts to capture light energy and convert carbon dioxide into oxygen and sugars. About half of photosynthesis on earth occurs in single-celled organisms like algae, making them absolutely essential for the global ecosystem, including for human survival. Many algae maximize the use of light by growing during the day and dividing at night. These algae often have a single, large chloroplast that is divided along with the cell, indicating that exquisite communication between the chloroplast and the rest of the cell controls the timing and orientation of both cell and chloroplast division. How cells coordinate cell and chloroplast division is a mystery, because chloroplast division depends on different genes than cell division. Understanding how cells coordinate these events will illuminate general principles of intracellular communication. Insights into the regulation of chloroplast division will also improve society’s capacity to leverage single-celled photosynthetic organisms to mitigate climate change. The Fellow will use Chlamydomonas reinhardtii to define the intracellular communication mechanisms underlying the spatiotemporal coordination of cell and chloroplast division in unicellular algae. Based on prior work, the Fellow hypothesizes that cytoskeletal structures mediate the spatial coordination of cell and chloroplast division, and that cell cycle regulators temporally control both processes. Using CRISPR-mediated gene knockout and fluorescence labelling, the Fellow will construct strains and perform live-cell microscopy to test these hypotheses. The Fellow will also pursue dual strategies to identify novel genes and proteins involved in the coordination of cell and chloroplast division: robotics-assisted, high-throughput forward genetic screens, and proximity-based protein labeling with mass spectrometry, using known and newly identified components involved in the process. These projects will promote the Fellow’s training in new genetic techniques and in biochemistry. The Fellow has designed a broader impacts program that will increase the participation of groups underrepresented in biology by developing a cross-institutional mentoring and support program for Black female postdoctoral fellows in biology in the Research Triangle. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.