- THIS ARTICLE
- Full Text
- Full Text (PDF)
-
All Versions of this Article:
genetics.106.064576v1
175/3/1117 most recent - Alert me when this article is cited
- Alert me if a correction is posted
- SERVICES
- Similar articles in this journal
- Similar articles in PubMed
- Alert me to new issues of the journal
- Download to citation manager
- Reprints & Permissions
- CITING ARTICLES
- Citing Articles via HighWire
- Citing Articles via Google Scholar
- GOOGLE SCHOLAR
- Articles by Williams, E. H.
- Articles by Fox, T. D.
- Search for Related Content
- PUBMED
- PubMed Citation
- Articles by Williams, E. H.
- Articles by Fox, T. D.
Originally published as Genetics Published Articles Ahead of Print on December 28, 2006.
Genetics, Vol. 175, 1117-1126, March 2007, Copyright © 2007
doi:10.1534/genetics.106.064576
Translation Initiation in Saccharomyces cerevisiae Mitochondria: Functional Interactions Among Mitochondrial Ribosomal Protein Rsm28p, Initiation Factor 2, Methionyl-tRNA-Formyltransferase and Novel Protein Rmd9p
Elizabeth H. Williams*,1,
Christine A. Butler*,
Nathalie Bonnefoy
and
Thomas D. Fox*,2
* Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York 14853 and Centre de Génétique Moléculaire, CNRS, 91198 Gif-sur-Yvette Cedex, France
2 Corresponding author: Department of Molecular Biology and Genetics, 333 Biotechnology Bldg., Cornell University, Ithaca, NY 14853-2703.
E-mail: tdf1{at}cornell.edu
Rsm28p is a dispensable component of the mitochondrial ribosomal small subunit in Saccharomyces cerevisiae that is not related to known proteins found in bacteria. It was identified as a dominant suppressor of certain mitochondrial mutations that reduced translation of the COX2 mRNA. To explore further the function of Rsm28p, we isolated mutations in other genes that caused a synthetic respiratory defective phenotype together with rsm28
. These mutations identified three nuclear genes: IFM1, which encodes the mitochondrial translation initiation factor 2 (IF2); FMT1, which encodes the methionyl-tRNA-formyltransferase; and RMD9, a gene of unknown function. The observed genetic interactions strongly suggest that the ribosomal protein Rsm28p and Ifm1p (IF2) have similar and partially overlapping functions in yeast mitochondrial translation initiation. Rmd9p, bearing a TAP-tag, was localized to mitochondria and exhibited roughly equal distribution in soluble and membrane-bound fractions. A small fraction of the Rmd9-TAP sedimented together with presumed monosomes, but not with either individual ribosomal subunit. Thus, Rmd9 is not a ribosomal protein, but may be a novel factor associated with initiating monosomes. The poorly respiring rsm28, rmd9-V363I double mutant did not have a strong translation-defective phenotype, suggesting that Rmd9p may function upstream of translation initiation, perhaps at the level of localization of mitochondrially coded mRNAs.
This article has been cited by other articles:
 |
|
 |
|
  C. Nouet, M. Bourens, O. Hlavacek, S. Marsy, C. Lemaire, and G. Dujardin Rmd9p Controls the Processing/Stability of Mitochondrial mRNAs and Its Overexpression Compensates for a Partial Deficiency of Oxa1p in Saccharomyces cerevisiae Genetics, March 1, 2007; 175(3): 1105 - 1115. [Abstract] [Full Text] [PDF]
|
|