Meeting Abstract

P2.53  Wednesday, Jan. 5  Function and expression dynamics of Rho, Rac and Cdc42 genes in the starlet sea anemone, Nematostella vectensis KHALILI, Setareh*; MAGIE, Craig R.; California State University, Fresno; California State University, Fresno starlight406@mail.fresnostate.edu

Cnidaria is the sister group to the Bilateria, which is composed of bilaterally-symmetric organisms such as humans, fruit flies, and soil nematodes. Among anthozoan cnidarians, the starlet sea anemone Nematostella vectensis has recently emerged as an important developmental model system for use in studies aimed at inferring character states ancestral to the evolution of the Bilateria. The objective of this study is to examine the patterns of gene expression and function of the Rho family of small GTPases (including Rho, Rac, and Cdc42) during development in the starlet sea anemone, Nematostella vectensis. Members of the Rho subfamily of Ras-related small GTPases are known principally for their pivotal role in regulating the actin cytoskeleton. They also have the ability to influence cell polarity, adhesion, microtubule dynamics, membrane transport pathways and transcription factor activity. We have observed that Rho and Rac genes are ubiquitously expressed throughout the embryo at the gastrula stage, whereas Cdc42 has a higher level of expression in the endoderm layer. The expression levels of Rho and Rac genes increase in the endoderm during planula stage, and the Cdc42 expression remains high in the endoderm. These results emphasize the importance of Rho GTPases in cytoskeletal regulation and cell adhesion during the early developmental stages of Nematostella vectensis. Knocking down gene expression via microinjection of splice-blocking morpholinos during gastrula, planula, and polyp stages, and analyzing the phenotype of the surviving embryos will provide further insight regarding gene function.