A Deathly DNase Activity for Dicer

Sloan-Kettering Institute, Department of Developmental Biology, 1275 York Ave, Box 252, New York, NY 10065, USA.
Developmental Cell (Impact Factor: 9.71). 05/2010; 18(5):692-4. DOI: 10.1016/j.devcel.2010.05.004
Source: PubMed


RNase III enzymes are a widely distributed family of double stranded RNA (dsRNA)-specific ribonucleases. Since the discovery of E. coli RNase III in the 1960s, the functions of this protein family in ribosomal RNA biogenesis and mRNA decay or regulation have been well studied in bacteria and yeast (MacRae and Doudna, 2007). Importance of their homologs in higher eukaryotes was recognized only in the last decade. In particular, Dicer-family RNase III enzymes are central to the biogenesis of Argonaute-associated small regulatory RNAs, including microRNAs (miRNAs) and small interfering RNAs (siRNAs). Because miRNAs play important roles in diverse biological settings, Dicer genes are essential for many aspects of development and physiology. The cell death pathway has critical connections with the miRNA pathway, since many individual miRNAs have proapoptotic or antiapoptotic activities. Deregulation of such miRNAs may contribute to various human cancers (Garzon et al., 2009).

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