Transcript Buffering: A Balancing Act between mRNA Synthesis and mRNA Degradation

Transcript buffering involves reciprocal adjustments between overall rates in mRNA synthesis and degradation to maintain similar cellular concentrations of mRNAs. This phenomenon was first discovered in yeast and encompasses coordination between the nuclear and cytoplasmic compartments. Transcript buffering was revealed by novel methods for pulse labeling of RNA to determine in vivo synthesis and degradation rates. In this Perspective, we discuss the current knowledge of transcript buffering. Emphasis is placed on the future challenges to determine the nature and directionality of the buffering signals, the generality of transcript buffering beyond yeast, and the molecular mechanisms responsible for this balancing. Steady-state mRNA levels are set by rates of transcription and degradation. Yeast studies revealed that global transcript levels are maintained by buffering synthesis and degradation. In this Perspective, Timmers and Tora discuss key aspects of transcript buffering, the nature of buffering signals, and the mechanism and generality of transcript buffering.