Accelerated mRNA decay in conditional mutants of yeast mRNA capping enzyme Journal Article


Authors: Schwer, B.; Mao, X.; Shuman, S.
Article Title: Accelerated mRNA decay in conditional mutants of yeast mRNA capping enzyme
Abstract: Current models of mRNA decay in yeast posit that 3' deadenylation precedes enzymatic removal of the 5' cap, which then exposes the naked end to 5' exonuclease action. Here, we analyzed gene expression in Saccharomyces cerevisiae cells bearing conditional mutations of Ceg1 (capping enzyme), a 52 kDa protein that transfers GMP from GTP to the 5' end of mRNA to form the GpppN cap structure. Shift of ceg1 mutants to restrictive temperature elicited a rapid decline in the rate of protein synthesis, which correlated with a sharp reduction in the steady-state levels of multiple individual mRNAs. ceg1 mutations prevented the accumulation of SSA1 and SSA4 mRNAs that were newly synthesized at the restrictive temperature. Uncapped poly(A)+ SSA4 mRNA accumulated in cells lacking the 5' exoribonuclease Xrn1. These findings provide genetic evidence for the long-held idea that the cap guanylate is critical for mRNA stability. The deadenylation-decapping-degradation pathway appears to be short-circuited when Ceg1 is inactivated.
Keywords: controlled study; gene deletion; mutation; nonhuman; messenger rna; saccharomyces cerevisiae; rna caps; rna, messenger; saccharomyces cerevisiae proteins; heat-shock response; rna splicing; rna, fungal; rna degradation; fungal proteins; rna capping; molecular stability; nucleotidyltransferases; heat-shock proteins; fungus mutant; polyadenylic acid; protein synthesis inhibitors; rna, small nuclear; exoribonucleases; priority journal; article; phosphodiesterase i
Journal Title: Nucleic Acids Research
Volume: 26
Issue: 9
ISSN: 0305-1048
Publisher: Oxford University Press  
Date Published: 1998-05-01
Start Page: 2050
End Page: 2057
Language: English
DOI: 10.1093/nar/26.9.2050
PUBMED: 9547258
PROVIDER: scopus
PMCID: PMC147543
DOI/URL:
Notes: Article -- Export Date: 12 December 2016 -- Source: Scopus
Altmetric
Citation Impact
BMJ Impact Analytics
MSK Authors
  1. Stewart H Shuman
    546 Shuman