Timing of transcription controls the selective translation of newly synthesized mRNAs during acute environmental stress

Abstract

When cells encounter stress, they rapidly mount an adaptive response by switching from pro-growth to stress-responsive gene expression programs. How cells selectively silence pre-existing, pro-growth transcripts yet efficiently translate transcriptionally induced stress mRNA and whether these transcriptional and post-transcriptional responses are coordinated are poorly understood. Here, we show that following acute glucose withdrawal in S. cerevisiae , pre-existing mRNAs are not first degraded to halt protein synthesis, nor are they sequestered away in P-bodies. Rather, their translation is quickly repressed through a sequence-independent mechanism that differentiates between mRNAs produced before and after stress, followed by their decay. Transcriptional induction of endogenous transcripts and reporter mRNAs during stress is sufficient to escape translational repression, while induction prior to stress leads to repression. Our results reveal a timing-controlled coordination of the transcriptional and translational responses in the nucleus and cytoplasm, ensuring a rapid and wide-scale reprogramming of gene expression following environmental stress. • Following acute glucose starvation, existing mRNAs are translationally repressed • Repressed mRNAs do not enrich in P-bodies and are degraded over time • Newly produced mRNAs, regardless of sequence, escape translation repression • A timing-controlled regulation couples translation and transcription under stress Under stress, cells adapt their gene expression programs through changes in transcription and translation. It is unclear how cells determine which mRNAs are translated or repressed. Zedan et al. show that the timing of mRNA production alone determines the selectivity of translation, thereby coupling the processes of transcription and translation.

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