MINIREVIEW: Insights into Hormonal Control of Messenger RNA Stability

Abstract

Until recently most studies of the regulation of eukaryotic mRNA levels have focused on the control of gene transcription. However, the level of a cellular mRNA actually represents a balance between its rates of synthesis and degradation. In the last few years the regulation of cytoplasmic mRNA stability has emerged as an important control point in a variety of biological systems (reviewed in Refs. 1–8). In this review we try to relate what is known about the regulation of mRNA stability in several intensively studied systems to the emerging area of hormonal control of mRNA stability. A useful working hypothesis is that most mRNAs are relatively stable in cells until subjected to an initial endonucleolytic cleavage. The 5′ and 3′ ends of most eukaryotic mRNAs are protected from exonucleolytic attack by the presence of a 5′ cap structure (9) and a 3′ poly(A) tract (10) complexed to a poly(A)-binding protein (11). Intramolecular cleavage by an endonuclease or removal of the protective poly(A) tract from the...