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 Liu, L.
Right arrow Articles by Dybvig, K.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Liu, L.
Right arrow Articles by Dybvig, K.

 Previous Article  |  Next Article 

Journal of Bacteriology, March 2002, p. 1335-1339, Vol. 184, No. 5
0021-9193/02/$04.00+0     DOI: 10.1128/JB.184.5.1335-1339.2002
Copyright © 2002, American Society for Microbiology. All Rights Reserved.

Trinucleotide GAA Repeats Dictate pMGA Gene Expression in Mycoplasma gallisepticum by Affecting Spacing between Flanking Regions

*** Li Liu,1 Victor S. Panangala,2 and Kevin Dybvig1*

Department of Genomics and Pathobiology, University of Alabama at Birmingham, Birmingham, Alabama 35294,1 Department of Pathobiology, College of Veterinary Medicine, Auburn University, Auburn, Alabama 368492

Received 18 July 2001/ Accepted 2 November 2001

The pMGA genes of the avian respiratory pathogen Mycoplasma gallisepticum encode a family of hemagglutinins that are subject to phase variation. A trinucleotide GAA repeat region is located upstream of the pMGA transcription start site. The length of the repeat region varies at a high frequency due to changes in the number of repeat units. Previous studies have shown that pMGA genes are transcribed when 12 GAA repeats are present but are not transcribed when the number of repeats is not 12. To further analyze the mechanism of gene regulation, the pMGA promoter region was modified either by deleting the nucleotides 5" of the GAA repeats or by inserting linkers of 10 or 12 bp at a position 3" of the repeats. The modified promoter region was fused to a promoterless lacZ gene and transformed into M. gallisepticum by using transposon Tn4001 as a vector. Transformants and successive generations of progeny were analyzed with 5-bromo-4-chloro-3-indolyl-ß-D-galactopyranoside (X-Gal) to monitor ß-galactosidase activity. For the transformants of M. gallisepticum containing the reporter with deletion of nucleotides 5" of the GAA repeats, GAA-dependent pMGA gene regulation was abolished. For the transformants containing the reporter with an addition of 10- or 12-bp linkers, lacZ was expressed only when eight GAA repeats were present. These data indicate that the nucleotides 5" of the GAA repeats as well as the spacing between the GAA repeats and sequences downstream (3") of the repeats are important for pMGA gene expression.

* Corresponding author. Mailing address: Department of Genomics and Pathobiology, Volker Hall, Room 223, University of Alabama at Birmingham, Birmingham, AL 35294-0019. Phone: (205) 934-9327. Fax: (205) 975-4418. E-mail: dybvig{at}uab.edu.

Journal of Bacteriology, March 2002, p. 1335-1339, Vol. 184, No. 5
0021-9193/02/$04.00+0     DOI: 10.1128/JB.184.5.1335-1339.2002
Copyright © 2002, American Society for Microbiology. All Rights Reserved.



This article has been cited by other articles:

  • Attia, A. S., Hansen, E. J. (2006). A Conserved Tetranucleotide Repeat Is Necessary for Wild-Type Expression of the Moraxella catarrhalis UspA2 Protein. J. Bacteriol. 188: 7840-7852 [Abstract] [Full Text]  
  • Mrazek, J. (2006). Analysis of Distribution Indicates Diverse Functions of Simple Sequence Repeats in Mycoplasma Genomes. Mol Biol Evol 23: 1370-1385 [Abstract] [Full Text]  
  • Martin, P., Makepeace, K., Hill, S. A., Hood, D. W., Moxon, E. R. (2005). Microsatellite instability regulates transcription factor binding and gene expression. Proc. Natl. Acad. Sci. USA 102: 3800-3804 [Abstract] [Full Text]  
  • Otsuka, Y., Parniewski, P., Zwolska, Z., Kai, M., Fujino, T., Kirikae, F., Toyota, E., Kudo, K., Kuratsuji, T., Kirikae, T. (2004). Characterization of a Trinucleotide Repeat Sequence (CGG)5 and Potential Use in Restriction Fragment Length Polymorphism Typing of Mycobacterium tuberculosis. J. Clin. Microbiol. 42: 3538-3548 [Abstract] [Full Text]  
  • Winner, F., Markova, I., Much, P., Lugmair, A., Siebert-Gulle, K., Vogl, G., Rosengarten, R., Citti, C. (2003). Phenotypic Switching in Mycoplasma gallisepticum Hemadsorption Is Governed by a High-Frequency, Reversible Point Mutation. Infect. Immun. 71: 1265-1273 [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»