Examining the immediate early targets of Gata4 and Gata5.. Xenopus laevis

Gata factors are amongst the genes expressed early on in the process of cardiogenesis. We used microarrays to examine the immediate early targets of Gata4 and Gata5 in the Xenopus leavis animal cap cardiogenesis model. We hope to use these data to examine the roles of Gata4 and Gata5 in cardiogenesis and also to begin to dissect out the common and distinct targets of Gata4 and Gata5. Keywords: genetic modification, gene overexpresison. Overall design: Xenopus leavis embryos were injected at the one cell stage with dexamethasone-inducible Gata4 or Gata5 mRNA constructs (to examine endodermal and mesodermal targets) or with Gata4 in the presence of Dkk1 (to examine mesodermal targets.) Embryos were cultured to stage 9, whereupon animal caps were excised and cultured for 2.5 hours in media containing dexamethasone to induce the constructs and cycloheximide to block de novo protein synthesis and thus give only immediate early targets.