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 Wang, X.
Right arrow Articles by Michels, C. A.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Wang, X.
Right arrow Articles by Michels, C. A.

 Previous Article  |  Next Article 

Eukaryotic Cell, October 2002, p. 696-703, Vol. 1, No. 5
1535-9778/02/$04.00+0     DOI: 10.1128/EC.1.5.696-703.2002
Copyright © 2002, American Society for Microbiology. All Rights Reserved.

Intracellular Maltose Is Sufficient To Induce MAL Gene Expression in Saccharomyces cerevisiae

Xin Wang, Mehtap Bali, Igor Medintz,{dagger} and Corinne A. Michels*

Queens College and Graduate School of City University of New York Biology Department, Flushing, New York 11367

Received 10 May 2002/ Accepted 26 June 2002

The presence of maltose induces MAL gene expression in Saccharomyces cells, but little is known about how maltose is sensed. Strains with all maltose permease genes deleted are unable to induce MAL gene expression. In this study, we examined the role of maltose permease in maltose sensing by substituting a heterologous transporter for the native maltose permease. PmSUC2 encodes a sucrose transporter from the dicot plant Plantago major that exhibits no significant sequence homology to maltose permease. When expressed in Saccharomyces cerevisiae, PmSUC2 is capable of transporting maltose, albeit at a reduced rate. We showed that introduction of PmSUC2 restores maltose-inducible MAL gene expression to a maltose permease-null mutant and that this induction requires the MAL activator. These data indicate that intracellular maltose is sufficient to induce MAL gene expression independently of the mechanism of maltose transport. By using strains expressing defective mal61 mutant alleles, we demonstrated a correlation between the rate of maltose transport and the level of the induction, which is particularly evident in medium containing very limiting concentrations of maltose. Moreover, our results indicate that a rather low concentration of intracellular maltose is needed to trigger MAL gene expression. We also showed that constitutive overexpression of either MAL61 maltose permease or PmSUC2 suppresses the noninducible phenotype of a defective mal13 MAL-activator allele, suggesting that this suppression is solely a function of maltose transport activity and is not specific to the sequence of the permease. Our studies indicate that maltose permease does not function as the maltose sensor in S. cerevisiae.

* Corresponding author. Mailing address: Queens College and Graduate School of CUNY Biology Department, 65-30 Kissena Blvd., Flushing, NY 11367. Phone: (718) 997-3400. Fax: (718) 997-3321. E-mail: Corinne_michels{at}qc.edu.

{dagger} Present address: Center for Bio/Molecular Science and Engineering, U.S. Naval Research Laboratory, Washington, DC 20375.

Eukaryotic Cell, October 2002, p. 696-703, Vol. 1, No. 5
1535-9778/02/$04.00+0     DOI: 10.1128/EC.1.5.696-703.2002
Copyright © 2002, American Society for Microbiology. All Rights Reserved.



This article has been cited by other articles:

  • Alves, S. L. Jr., Herberts, R. A., Hollatz, C., Trichez, D., Miletti, L. C., de Araujo, P. S., Stambuk, B. U. (2008). Molecular Analysis of Maltotriose Active Transport and Fermentation by Saccharomyces cerevisiae Reveals a Determinant Role for the AGT1 Permease. Appl. Environ. Microbiol. 74: 1494-1501 [Abstract] [Full Text]  
  • Wang, X., Michels, C. A. (2004). Mutations in SIN4 and RGR1 Cause Constitutive Expression of MAL Structural Genes in Saccharomyces cerevisiae. Genetics 168: 747-757 [Abstract] [Full Text]  
  • Jules, M., Guillou, V., Francois, J., Parrou, J.-L. (2004). Two Distinct Pathways for Trehalose Assimilation in the Yeast Saccharomyces cerevisiae. Appl. Environ. Microbiol. 70: 2771-2778 [Abstract] [Full Text]  
  • Bali, M., Zhang, B., Morano, K. A., Michels, C. A. (2003). The Hsp90 Molecular Chaperone Complex Regulates Maltose Induction and Stability of the Saccharomyces MAL Gene Transcription Activator Mal63p. J. Biol. Chem. 278: 47441-47448 [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»