Format

Send to

Choose Destination
Mol Biol Cell. 2009 Jul;20(13):3025-32. doi: 10.1091/mbc.E09-01-0028. Epub 2009 May 6.

Analysis of Dom34 and its function in no-go decay.

Author information

1
University of Arizona, Department of Molecular and Cellular Biology and Howard Hughes Medical Institute, Tucson, AZ 85721, USA.

Abstract

Eukaryotic mRNAs are subject to quality control mechanisms that degrade defective mRNAs. In yeast, mRNAs with stalls in translation elongation are targeted for endonucleolytic cleavage by No-Go decay (NGD). The cleavage triggered by No-Go decay is dependent on Dom34p and Hbs1p, and Dom34 has been proposed to be the endonuclease responsible for mRNA cleavage. We created several Dom34 mutants and examined their effects on NGD in yeast. We identified mutations in several loops of the Dom34 structure that affect NGD. In contrast, mutations inactivating the proposed nuclease domain do not affect NGD in vivo. Moreover, we observed that overexpression of the Rps30a protein, a high copy suppressor of dom34Delta cold sensitivity, can restore some mRNA cleavage in a dom34Delta strain. These results identify important functional regions of Dom34 and suggest that the proposed endonuclease activity of Dom34 is not required for mRNA cleavage in NGD. We also provide evidence that the process of NGD is conserved in insect cells. On the basis of these results and the process of translation termination, we suggest a multistep model for the process of NGD.

PMID:
19420139
PMCID:
PMC2704154
DOI:
10.1091/mbc.e09-01-0028
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Atypon Icon for PubMed Central
Loading ...
Support Center