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Buffering exogenous perturbation is crucial to maintain transcriptional homeostasis during development.While miRNAs have been speculated to play a role in stability maintenance,previous studies seeking to check this conjecture focused on measurements of transcript levels at steady state or involved individual miRNA targets.We measured whole-genome expression dynamics by introducing a transient perturba-tion and establishing a perturbation and recovery system in Drosophila larvae.We inhibited all transcrip-tion and assayed transcriptomes at several time points during recovery from inhibition.We performed these experiments in the wild type and miRNA-deficient genetic backgrounds.Consistent with theories about miRNAs'function in stabilizing the transcriptome,we find that attenuating miRNA expression leads to weak impairment in degradation of targets but strong destabilization of target genes when tran-scription is re-activated.We further fitted a model that captures the essential aspects of transcription dynamics in our experiments and found that the miRNA target transcripts uniformly overshoot the orig-inal steady state as they recover from a general inhibition of transcription if global miRNA levels are reduced.Collectively,our results provide experimental evidence for the idea that miRNAs act cumula-tively to stabilize the transcriptional regulatory network.We therefore found a promising approach to assess the effect of these molecules on transcription dynamics.