Spatially regulated mRNA decay sharpens expression patterns in the Drosophila embryo.
Abstract:
The regulation of mRNA decay is important for numerous cellular and developmental processes. Here, we use the patterning gene even-skipped (eve) in the early Drosophila embryo to investigate the contribution of mRNA decay to shaping mature expression patterns. Through P-body colocalisation analysis and mathematical modelling of live and fixed imaging data, we present evidence that eve mRNA stability is regulated across stripe 2, with enhanced mRNA decay at the edges of the stripe. To manipulate mRNA stability, we perturbed mRNA decay in the embryo by optogenetic degradation of the 5’ to 3’ exoribonuclease Pacman (Pcm). Depleting Pcm results in larger P-bodies, which accumulate eve mRNAs, and disrupted eve expression patterns. Overall, these data show how eve mRNA instability can function with transcriptional regulation to define sharp expression domain borders. We discuss how spatially regulated mRNA stability may be widely used to sculpt expression patterns during development.
