Dynamic regulation of <i>eve</i> stripe 2 expression reveals transcriptional bursts in living <i>Drosophila</i> embryos

Abstract

Significance There is considerable information about the spatial regulation of gene expression during pattern formation in animal development. Significantly less is known about temporal control, in part due to our inability to analyze gene activity in real time. Using a recently developed approach for the visualization of gene expression in living Drosophila embryos, we examined the well-known even-skipped stripe 2 expression pattern. Surprisingly, we observe that this classic pattern is quite transient and generated by discontinuous surges of transcriptional activity in individual cells. These results challenge a purely static framework for dissecting developmental programs and emphasize the importance of the dynamic features of pattern formation.