Nucleic Acid Synthesis/Breakdown: RNA Synthesis/Function – The Interplay Between Eukaryotic mRNA Degradation and Translation

Abstract

The degradation of mRNA is one of the critical aspects of gene regulation. mRNAs for regulatory proteins in cytoplasm must be degraded to ensure that nuclear regulatory decisions are manifested as novel or developmentally regulated cytoplasmic events. In other words, ceasing mRNA transcription in response to environmental or physiological cues is irrelevant as long as cytoplasmic mRNA exists or is translated. Eventually, each mRNA must be degraded, in a controlled way to assure the correct continuation of cellular processes. From this, it can be said that mRNA decay contributes significantly to the proteomes’ overall architecture by allowing cells to adapt to environmental and physiological change quickly and promptly. Although much is known about mRNA decay in eukaryotes, understanding how the process is modulated is far from complete. mRNA translation is known to be tightly integrated with mRNA decay. In the last few years, work has concentrated on this relationship to elucidate the regulation of mRNA decay in the context of translation. From this, two views have arisen. The first suggests that mRNA must be removed from ribosomes to be destroyed in ribosome-free areas. The other view proposes mRNA decay occurs in concert with protein synthesis. In this article, we summarize the current understanding of how eukaryotic mRNA decay interconnects with mRNA translation within the cell with an attempt to reconcile these two views and suggest important areas for future investigation.