Philippe, Sophia: The Wonders of Cell Migration: Analysis of Two Actin Regulators
Title: The Wonders of Cell Migration: Analysis of Two Actin Regulators
Name: Sophia Philippe
Home Institute: New Jersey City University
Programs: RISE program, INSPIRE Postdoctoral Research and Education Program
Other contributors: Martha Soto, DenverJean-Baptiste, Sushma Mannimala, Thejasvi Venkatachalam and Karla Larios
Abstract: Healthy embryonic development is essential for human life and understanding how it works could help many people. Actin regulates embryonic development and is involved in processes like cell migration. The Rho GTPases, controlled by a large family of GEFs (Guanine Exchange Factors), regulate actin dynamics in cells. During C. elegans embryonic morphogenesis, the GTPase CED-10/Rac1 plays a major role in activating ventral enclosure, a migration resulting in the embryo’s enclosure by epidermal cells. However, the GEF activating CED-10/Rac1 hasn’t been identified. My project is to analyze F-actin organization during cell migrations under GEF control to analyze possible GEFs for the GTPase CED-10/Rac1. First, we tested if loss of GEF VAV-1 affected cell migrations, and found it did. Then, we compared C. elegans VAV-1 to human VAV-1, -2, and -3 and thought about how VAV-1 may help embryos. We also examined the GEF CED-12(ELMO)/CED-5(DOCK180), which affects cell migrations in the epidermis and when engulfing dying cells, as a possible regulator of the same GTPase. Our analysis suggested CED-12/ELMO may have both positive and negative effects on F-actin. Therefore we compared the ELMO half of the GEF protein, CED-12(ELMO) in C. elegans to six different ELMO proteins in humans and six different ELMOS in slime mold Dictyostelium. After better understanding CED-12, we predicted that it’d behave as both a positive and negative regulator of Rac1/CED-10. Also, CED-12/ELMO has been shown to sometimes promote and sometimes block actin nucleation through Rac1(CED-10 in worms). We used the Wormbase, NCBI Blast and CLUSTALW softwares, and fluorescence to visually analyze the proteins and compare them. We mutated some GEF proteins and analyzed their effects in C. elegans by counting their percent lethality over death in both wild type and the mutant embryos.
Biography: Sophia Keila Philippe is a senior at New Jersey City University, pursuing a major in Biology. Sophia moved from Haiti to the United States with her family after the major Haitian earthquake in 2010. She’s trilingual: Haitian Creole, English, and French. She always remains active on campus by being a Supplemental Instruction Leader, where she facilitates group studies in biology, chemistry, and algebra courses for undergraduate students. During the academic year, she works in a molecular biology lab, with Dr. Anthony Esposito as her mentor. Sophia also managed to be the secretary of the Haitian Students Association last year and has been a facilitator for the National Society of Leadership and Success at NJCU. She plans to pursue an M.D/Ph.D in Genetic Counseling after graduating.