Article

The meaning of nonsense.

Institute of Cell Biology, University of Berne, Baltzerstrabetae 4, 3012 Berne, Switzerland.
Trends in cell biology (impact factor: 12.12). 07/2008; 18(7):315-21. DOI:10.1016/j.tcb.2008.04.005
Source: PubMed

ABSTRACT To ensure the accuracy of gene expression, eukaryotes have evolved several surveillance mechanisms. One of the best-studied quality control mechanisms is nonsense-mediated mRNA decay (NMD), which recognizes and degrades transcripts harboring a premature translation-termination codon (PTC), thereby preventing the production of faulty proteins. NMD regulates approximately 10% of human mRNAs, and its physiological importance is manifested by the fact that approximately 30% of disease-associated mutations generate PTCs. Although different mechanisms of PTC recognition have been proposed for different species, recent studies in Saccharomyces cerevisiae, Drosophila melanogaster, Caenorhabditis elegans, plants and mammals suggest a conserved model. Here, we summarize the latest results and discuss an emerging model for NMD and its implications for the regulation of gene expression.

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Keywords

best-studied quality control mechanisms
 
Caenorhabditis elegans
 
degrades transcripts harboring
 
different species
 
disease-associated mutations
 
faulty proteins
 
gene expression
 
human mRNAs
 
implications
 
latest results
 
mammals
 
NMD
 
physiological importance
 
premature translation-termination codon
 
PTC
 
PTC recognition
 
PTCs
 
Saccharomyces cerevisiae