Mesp1-induced gene expression changes. Mus musculus

During gastrulation, cells of the prospective mesoderm ingress through the primitive streak and acquire fates based on complex spatial and temporal cues. Progenitors of the cardiogenic mesoderm are first found at E6.5 in the posterior lateral epiblast and subsequently migrate laterally and anteriorly to form the cardiac crescent at E7.5, when regionalized cell fates are first delineated . Lineage tracing and heterotopic transplantation studies suggest that precursors in the earliest heart field possess potential to generate myocardium, endocardium, and pericardium. The mechanisms by which inductive signals in the primitive streak effect the development of this pancardiac progenitor field, however, remain poorly understood In mice, the earliest restricted progenitors of the cardiovascular system are marked by expression of the basic helix-loop-helix transcription factor, Mesp1. We therefore use microarray analysis to determine the early and intermediate effects of transiently forced Mesp1 expression during ES cell differentiation. Keywords: time course Overall design: ES cells bearing a targeted, doxycycline inducible Mesp1 transgene were differentiated in the absence or presence of DKK1 from day 0-4, either with or without transient doxycycline treatment from day 2-4.