66.10 Friday, Jan. 6 Resetting the clock: Temporal dynamics in gene network evolution WOZNICA, A; HAUSLER, M; JEMMET, J; STAROBINSKA, E; LI, Y; DAVIDSON, B*; UC Berkeley; UC Santa Cruz; University of Arizona; University of Arizona; University of Arizona; University of Arizona email@example.com
Spatial shifts in gene expression domains have well documented roles in evolution. In contrast, the precise evolutionary contribution of temporal expression dynamics remains poorly characterized. We are studying the gene regulatory network underlying heart lineage specification in the invertebrate chordate, Ciona intestinalis. Microarray analysis has delineated distinct temporal clusters of heart genes that are up-regulated within the first two hours of specification. Through both in-silico and wet bench analysis, we have begun to unravel the regulatory logic mediating discrete temporal gene expression. Our findings suggest that both early and late heart genes are regulated by the same primary transcription factor, Ets1/2. However, Ets1/2 pairs with distinct co-factors to generate differential temporal outputs. We are currently exploring how this "paired input" regulatory logic may influence the robustness of temporal gene regulation and thus constrain or potentiate adaptation.