Eukaryotic Cell
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
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 Todd, R. B.
Right arrow Articles by Hynes, M. J.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Todd, R. B.
Right arrow Articles by Hynes, M. J.

 Previous Article  |  Next Article 

Eukaryotic Cell, October 2005, p. 1646-1653, Vol. 4, No. 10
1535-9778/05/$08.00+0     doi:10.1128/EC.4.10.1646-1653.2005
Copyright © 2005, American Society for Microbiology. All Rights Reserved.

Nuclear Accumulation of the GATA Factor AreA in Response to Complete Nitrogen Starvation by Regulation of Nuclear Export

Richard B. Todd, James A. Fraser,{dagger} Koon Ho Wong, Meryl A. Davis, and Michael J. Hynes*

Department of Genetics, The University of Melbourne, Victoria 3010, Australia

Received 21 June 2005/ Accepted 21 July 2005

Both the availability and the quality of nutrients affect cellular functions by controlling gene activity. AreA, a member of the GATA family of transcription factors, globally activates expression of genes involved in nitrogen source utilization in Aspergillus nidulans. The quality of the nitrogen source determines the level and activation capacity of AreA through controls at the level of areA mRNA stability and by interaction of AreA with the corepressor NmrA. The availability of potential nitrogen sources also affects the activation capacity of AreA. We show that the complete absence of a nitrogen source results in an enhanced level of AreA-dependent gene expression and that this response is independent of mechanisms regulating AreA activity in response to nitrogen source quality. During nitrogen starvation AreA accumulates in the nucleus, but the presence of a potential nitrogen source or carbon starvation prevents this accumulation. Furthermore, accumulated AreA is rapidly lost from the nuclei of nitrogen-starved cells when a nitrogen source is supplied or when a carbon source is absent, and this accompanies arrest of the AreA-dependent nitrogen starvation response on regulated gene expression. By the generation of a leptomycin B-sensitive mutant, we have been able to show that nuclear exit occurs via the CrmA exportin. We conclude that sensing mechanisms discriminate between starvation and the presence of potential nutrients that can signal to the AreA transcription factor. Nitrogen source availability, but not quality, affects nuclear accumulation by regulating nuclear exit of AreA, providing a rapid response to changes in the supply of nutrients.

* Corresponding author. Mailing address: Department of Genetics, The University of Melbourne, Victoria 3010, Australia. Phone: 613 83446239. Fax: 613 83445139. E-mail: mjhynes{at}unimelb.edu.au.

{dagger} Present address: Department of Molecular Genetics and Microbiology, Howard Hughes Medical Institute, Duke University Medical Center, Durham, NC 27710.

Eukaryotic Cell, October 2005, p. 1646-1653, Vol. 4, No. 10
1535-9778/05/$08.00+0     doi:10.1128/EC.4.10.1646-1653.2005
Copyright © 2005, American Society for Microbiology. All Rights Reserved.



This article has been cited by other articles:



HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Appl. Environ. Microbiol. Infect. Immun. J. Bacteriol.
Mol. Cell Biol. Microbiol. Mol. Biol. Rev. ALL ASM JOURNALS
Copyright © 2005 by the American Society for Microbiology.