Modulation of Poly(A)-specific Ribonuclease (PARN): Current Knowledge and Perspectives
Abstract:Deadenylation is the exoribonucleolytic shortening of eukaryotic poly(A) tails. It is often the first and rate-limiting step for mRNA decay and translational silencing. The process is catalysed by a diversity of deadenylases, which provide robust and flexible means to control mRNA levels and gene expression. Poly(A)-specific ribonuclease (PARN) is a major mammalian deadenylase and the only known to concurrently bind the 5' cap-structure and the 3' poly(A), thus enhancing the degradation rate and amplifying its processivity. PARN is important during oocyte maturation, embryogenesis, early development, DNA damage, and in cell-cycle progression, but also in processes beyond mRNA metabolism, such as the maturation of snoRNAs. The enzyme also participates in nonsense-mediated mRNA decay and in the regulation of cytoplasmic polyadenylation. Importantly, PARN is involved in the degradation of several cancerrelated genes, while its expression is altered in cancer. Apart from the direct interaction with the cap structure, several strategies regulate PARN activity, such as phosphorylation, interaction with RNA-binding proteins (RBPs), and natural nucleotides. Recent studies have focused on the regulation of its activity by synthetic nucleoside analogues with therapeutic potential. In this context, the wide repertoire of RBPs and molecules that regulate PARN activity, together with the established role of deadenylases in miRNA-mediated regulation of mRNA expression, suggest that mRNA turnover is more complex than it was previously thought and PARN holds a key role in this process. In this review, we highlight the importance of PARN during RNA's lifecycle and discuss clinical perspectives of modulating its activity.
Document Type: Research Article
Publication date: October 1, 2012
More about this publication?
- Current Medicinal Chemistry covers all the latest and outstanding developments in medicinal chemistry and rational drug design. Each issue contains a series of timely in-depth reviews written by leaders in the field covering a range of the current topics in medicinal chemistry. Current Medicinal Chemistry is an essential journal for every medicinal chemist who wishes to be kept informed and up-to-date with the latest and most important developments.