Meeting Abstract

S4-2.2  Saturday, Jan. 5  The first steps toward a Nematostella gene interaction network FISCHER, Antje H.L.*; COSENTINO, Carlo; SMITH, Joel; MBL; Università degli Studi Magna Graecia Catanzaro; MBL afischer@mbl.edu

Cnidarians, the sister group to Bilaterians, are particularly interesting for understanding the evolution of fundamental developmental programs, such as axis specification, gastrulation and germ layer specification. Many genes known to be involved in embryonic patterning in Bilaterians are also found in Cnidarians. However, little is known about how these genes are regulated, i.e., the gene regulatory network (GRN). The sea anemone Nematostella vectensis has emerged as a particularly suitable cnidarian model system for GRN studies. We present our first steps towards resolving the GRN for early development in Nematostella. Using an Illumina HiSeq to perform quantitative RNA-seq, we established a high-density gene expression time course, from fertilization to gastrulation. We compare absolute transcript levels for each gene with all others to determine the statistical dependencies between all gene pairs, a measure of genetic interaction. Additional information about putative regulatory gene interactions is provided by targeted perturbations of signaling pathways. The resulting interaction network (“interactome”) will offer first insights into which genes are the most interconnected. These core regulators will provide the starting point for more detailed network analyses. The obtained GRN will be compared to other organisms to gain a deeper understanding about the evolution of developmental programs across metazoans. As a starting point for the comparison we are performing quantitative RNA-seq experiments on high-density developmental time courses in the snail Crepidula fornicata and the ctenophore Mnemiopsis leidyi.