EXPRESSION LEVELS OF VASA, PAX-1 LIKE INTERACTING, AND GERANYL-GERANYL TRANSFERASE ACROSS DEVELOPMENTAL STAGES OF THE WASP Copidosoma floridanum

Abstract

The parasitic, polyembryonic wasp Copidosoma floridanum is useful for studying the evolution of development because it has evolved a novel phase of development, the proliferation phase. C. floridanum development begins when females oviposit eggs into a lepidopteran host egg. After an egg is laid, it undergoes cell division to form a morula. However, instead of then initiating morphogenesis, as commonly occurs in organisms, morphogenesis is delayed in favor of continued cell division during the proliferation phase. During proliferation, invagination of a surrounding membrane parcels groups of dividing cells into independently developing embryos. This mass of embryos, a polymorula, gives rise to thousands of genetically identical sibling embryos. These embryos undergo morphogenesis to form larvae. To investigate the molecular regulation of proliferation and the switch to morphogenesis in C. floridanum, quantitative PCR (qPCR) was used to measure the level of expression of 3 candidate genes, vasa, pax-1-like-interacting, and geranyl-geranyl transferase. Prior work suggests that these genes have roles in cell division or morphogenesis in other animals and that they are expressed at these stages in C. floridanum. However, expression of these genes has not been examined at a finer time scale or quantified in C. floridanum. Results will show the level of gene expression between proliferation and morphogenesis stages. Different levels of gene expression across these developmental stages suggest a gene could be a good candidate for future functional studies, while displaying consistent levels of expression suggest it is likely are not involved in regulating proliferation or the switch from proliferation to morphogenesis.