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 Kebaara, B. W.
Right arrow Articles by Atkin, A. L.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Kebaara, B. W.
Right arrow Articles by Atkin, A. L.

 Previous Article  |  Next Article 

Eukaryotic Cell, June 2008, p. 980-987, Vol. 7, No. 6
1535-9778/08/$08.00+0     doi:10.1128/EC.00357-07
Copyright © 2008, American Society for Microbiology. All Rights Reserved.

Candida albicans Tup1 Is Involved in Farnesol-Mediated Inhibition of Filamentous-Growth Induction{triangledown}

Bessie W. Kebaara,{dagger} Melanie L. Langford,{dagger} Dhammika H. M. L. P. Navarathna,{ddagger} Raluca Dumitru,§ Kenneth W. Nickerson, and Audrey L. Atkin*

School of Biological Sciences, University of Nebraska, Lincoln, Nebraska 68588-0666

Received 28 September 2007/ Accepted 9 April 2008

Candida albicans is a dimorphic fungus that can interconvert between yeast and filamentous forms. Its ability to regulate morphogenesis is strongly correlated with virulence. Tup1, a transcriptional repressor, and the signaling molecule farnesol are both capable of negatively regulating the yeast to filamentous conversion. Based on this overlap in function, we tested the hypothesis that the cellular response to farnesol involves, in part, the activation of Tup1. Tup1 functions with the DNA binding proteins Nrg1 and Rfg1 as a transcription regulator to repress the expression of hypha-specific genes. The tup1/tup1 and nrg1/nrg1 mutants, but not the rfg1/rfg1 mutant, failed to respond to farnesol. Treatment of C. albicans cells with farnesol caused a small but consistent increase in both TUP1 mRNA and protein levels. Importantly, this increase corresponds with the commitment point, beyond which added farnesol no longer blocks germ tube formation, and it correlates with a strong decrease in the expression of two Tup1-regulated hypha-specific genes, HWP1 and RBT1. Tup1 probably plays a direct role in the response to farnesol because farnesol suppresses the haploinsufficient phenotype of a TUP1/tup1 heterozygote. Farnesol did not affect EFG1 (a transcription regulator of filament development), NRG1, or RFG1 mRNA levels, demonstrating specific gene regulation in response to farnesol. Furthermore, the tup1/tup1 and nrg1/nrg1 mutants produced 17- and 19-fold more farnesol, respectively, than the parental strain. These levels of excess farnesol are sufficient to block filamentation in a wild-type strain. Our data are consistent with the role of Tup1 as a crucial component of the response to farnesol in C. albicans.

* Corresponding author. Mailing address: School of Biological Sciences, University of Nebraska, Lincoln, NE 68588-0666. Phone: (402) 314-5571. Fax: (402) 472-8722. E-mail: aatkin1{at}unl.edu

{triangledown} Published ahead of print on 18 April 2008.

{dagger} Bessie W. Kebaara and Melanie L. Langford contributed equally to this work.

{ddagger} Present address: Biomedical Pathology, NIH, Bethesda, MD 20892-1500.

§ Present address: Neuroscience Center, University of North Carolina, Chapel Hill, NC 27599.

Eukaryotic Cell, June 2008, p. 980-987, Vol. 7, No. 6
1535-9778/08/$08.00+0     doi:10.1128/EC.00357-07
Copyright © 2008, American Society for Microbiology. All Rights Reserved.



This article has been cited by other articles:

  • Rennemeier, C., Frambach, T., Hennicke, F., Dietl, J., Staib, P. (2009). Microbial Quorum-Sensing Molecules Induce Acrosome Loss and Cell Death in Human Spermatozoa. Infect. Immun. 77: 4990-4997 [Abstract] [Full Text]  
  • Ghosh, S., Navarathna, D. H. M. L. P., Roberts, D. D., Cooper, J. T., Atkin, A. L., Petro, T. M., Nickerson, K. W. (2009). Arginine-Induced Germ Tube Formation in Candida albicans Is Essential for Escape from Murine Macrophage Line RAW 264.7. Infect. Immun. 77: 1596-1605 [Abstract] [Full Text]  


Copyright © 2009 by the American Society for Microbiology.   For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»