This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Branicky, R.
Right arrow Articles by Hekimi, S.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Branicky, R.
Right arrow Articles by Hekimi, S.

 Previous Article  |  Next Article 

Molecular and Cellular Biology, May 2006, p. 3976-3985, Vol. 26, No. 10
0270-7306/06/$08.00+0     doi:10.1128/MCB.26.10.3976-3985.2006
Copyright © 2006, American Society for Microbiology. All Rights Reserved.

Uncoupling the Pleiotropic Phenotypes of clk-1 with tRNA Missense Suppressors in Caenorhabditis elegans

Robyn Branicky, Phuong Anh Thi Nguyen, and Siegfried Hekimi*

Department of Biology, McGill University, 1205 Avenue Docteur Penfield, Montreal, Quebec, Canada H3A 1B1

Received 13 September 2005/ Returned for modification 30 November 2005/ Accepted 7 February 2006

clk-1 encodes a demethoxyubiquinone (DMQ) hydroxylase that is necessary for ubiquinone biosynthesis. When Caenorhabditis elegans clk-1 mutants are grown on bacteria that synthesize ubiquinone (UQ), they are viable but have a pleiotropic phenotype that includes slowed development, behaviors, and aging. However, when grown on UQ-deficient bacteria, the mutants arrest development transiently before growing up to become sterile adults. We identified nine suppressors of the missense mutation clk-1(e2519), which harbors a Glu-to-Lys substitution. All suppress the mutant phenotypes on both UQ-replete and UQ-deficient bacteria. However, each mutant suppresses a different subset of phenotypes, indicating that most phenotypes can be uncoupled from each other. In addition, all suppressors restore the ability to synthesize exceedingly small amounts of UQ, although they still accumulate the precursor DMQ, suggesting that the presence of DMQ is not responsible for the Clk-1 phenotypes. We cloned six of the suppressors, and all encode tRNAGlu genes whose anticodons are altered to read the substituted Lys codon of clk-1(e2519). To our knowledge, these suppressors represent the first missense suppressors identified in any metazoan. The pattern of suppression we observe suggests that the individual members of the tRNAGlu family are expressed in different tissues and at different levels.


* Corresponding author. Mailing address: Department of Biology, McGill University, 1205 Ave. Docteur Penfield, Montreal, Quebec, Canada H3A 1B1. Phone: (514) 398-6440. Fax: (514) 398-1674. E-mail: siegfried.hekimi{at}mcgill.ca.


Molecular and Cellular Biology, May 2006, p. 3976-3985, Vol. 26, No. 10
0270-7306/06/$08.00+0     doi:10.1128/MCB.26.10.3976-3985.2006
Copyright © 2006, American Society for Microbiology. All Rights Reserved.




This article has been cited by other articles:

  • Wang, Y., Branicky, R., Stepanyan, Z., Carroll, M., Guimond, M.-P., Hihi, A., Hayes, S., McBride, K., Hekimi, S. (2009). The Anti-neurodegeneration Drug Clioquinol Inhibits the Aging-associated Protein CLK-1. J. Biol. Chem. 284: 314-323 [Abstract] [Full Text]  
  • Lapointe, J., Hekimi, S. (2008). Early Mitochondrial Dysfunction in Long-lived Mclk1+/- Mice. J. Biol. Chem. 283: 26217-26227 [Abstract] [Full Text]  
  • Gulmezian, M., Zhang, H., Javor, G. T., Clarke, C. F. (2006). Genetic Evidence for an Interaction of the UbiG O-Methyltransferase with UbiX in Escherichia coli Coenzyme Q Biosynthesis.. J. Bacteriol. 188: 6435-6439 [Abstract] [Full Text]