Project summary This diversity supplement to R01 GM135433 proposes to train graduate student Malek Elsayyid as she uses the strengths of the C. elegans system to define factors that regulate extracellular vesicle (EV) biogenesis as well as the physiological significance of EV shedding. Secreted EVs, are membrane wrapped structures that share protein, RNA, lipid, and metabolite cargo with recipient cells. Released from most if not all cell types, EVs play a critical role during physiological processes and in pathological conditions. In C. elegans, EVs bud from sensory neuron cilia, then are taken up by surrounding glia or discharged into the environment. We developed transgenic worms that express different fluorescently tagged EV cargoes at single copy and optimized imaging parameters to visualize secreted EVs. The scientific goals of this supplement are to define the role of small G-protein RAB-28 in EV biogenesis and determine the impact of phagocytosed EVs on glia. This supplement proposal includes a mentoring plan to maximize Ms. Elsayyid’s training and future success. Performing research as an undergrad at a small liberal arts school limited her access to specialized equipment and technical expertise. Further, the COVID-19 pandemic has significantly impacted Ms. Elsayyid’s graduate experiences. In her training, Ms. Elsayyid will focus on four key areas. First, she will learn advanced super resolution and TIRF microscopy skills as she brings her project from start to completion. Second, she will use these data for scientific writing, honing communication skills by writing abstracts, research manuscripts, grant proposals, and a thesis dissertation. Third, she will present her research at C. elegans community, Chemistry Biology Interface program, DE Neuroscience, and national/international meetings. Finally, she will gain leadership skills mentoring students in the lab, a course-based research experience, and the community. Ms. Elsayyid will be advised by a mentoring team at the University of Delaware (UD). Dr. Jessica Tanis, Ms. Elsayyid’s primary mentor is an Assistant Professor in the Department of Biological Sciences with > 16 years C. elegans experience and 5 years studying EVs. Dr. Jeffrey Caplan, the Director of BioImaging at UD who studies transfer of EVs between plants and fungi has technical expertise in the imaging platforms and image analysis software programs required to train Ms. Elsayyid for this project. Dr. Grimes, a Professor in the Department of Chemistry and Biochemistry and co-director of the NIH-funded Chemistry Biology Interface (CBI) Program at UD will focus on Ms. Elsayyid’s career development, meeting with her bi-annually to review her IDP and informally on a weekly basis at CBI meetings. In conclusion, development of research expertise, communication skills, and mentoring experience as well as participation in the UD CBI program and professional networking opportunities will help Ms. Elsayyid achieve her career goal of...