ABSTRACT
The yeast, Saccharomyces cerevisiae, has proven to be an ideal model system for the character ization of mRNA decay pathways, including those restricted to atypical transcripts. Early experi ments showing that nonsense mutations in the yeast URA1, URA3> H IS4y and LEU 2 genes accelerated the decay rates of the mRNAs transcribed from these genes led to the general recog nition of the mRNA-destabilizing effects of premature termination codons.1'3 When the UPF1 gene was shown to regulate this phenomenon3'5 an immediate and obvious question was whether the substrate specificity of its activity was limited to nonsense-containing mRNAs or extended to a broader range of potential targets. It seemed unlikely that the sole function of Upfl protein (Upflp) was anticipatory, i.e., dedicated to the rapid elimination of transcripts from nonsense alleles, and a survey of the abundance and half-lives of numerous mRNAs in wild-type and
*Corresponding Author: Allan Jacobson-Department of Molecular Genetics and Microbiology, University of Massachusetts Medical School, Worcester, Massachusetts 01655-0122, U.S.A. Email: allan.jacobson@umassmed.edu
Nonsense-Mediated mRNA Decay, edited by Lynne E. Maquat. ©2006 Eurekah.com.
