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 French, C. T.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Liu, L.
Right arrow Articles by French, C. T.

 Previous Article  |  Next Article 

Infection and Immunity, February 2000, p. 871-876, Vol. 68, No. 2
0019-9567/00/$04.00+0
Copyright © 2000, American Society for Microbiology. All rights reserved.

GAA Trinucleotide Repeat Region Regulates M9/pMGA Gene Expression in Mycoplasma gallisepticum

Li Liu,1 Kevin Dybvig,2 Victor S. Panangala,1,* Vicky L. van Santen,1 and Christopher T. French2

Department of Pathobiology, College of Veterinary Medicine, Auburn University, Auburn, Alabama 36849,1 and Department of Comparative Medicine and Microbiology, University of Alabama at Birmingham, Birmingham, Alabama 352942

Received 18 August 1999/Returned for modification 14 October 1999/Accepted 28 October 1999

Mycoplasma gallisepticum, the cause of chronic respiratory infections in the avian host, possesses a family of M9/pMGA genes encoding an adhesin(s) associated with hemagglutination. Nucleotide sequences of M9/pMGA gene family members indicate extensive sequence similarity in the promoter regions of both the transcribed and silent genes. The mechanism that regulates M9/pMGA gene expression is unknown, but studies have revealed an apparent correlation between gene expression and the number of tandem GAA repeat motifs located upstream of the putative promoter. In this study, transposon Tn4001 was used as a vector with the Escherichia coli lacZ gene as the reporter system to examine the role of the GAA repeats in M9/pMGA gene expression in M. gallisepticum. A 336-bp M9 gene fragment (containing the GAA repeat region, the promoter, and the translation start codon) was amplified by PCR, ligated with a lacZ gene from E. coli, and inserted into the Tn4001-containing plasmid pISM2062. This construct was transformed into M. gallisepticum PG31. Transformants were filter cloned on agar supplemented with 5-bromo-4-chloro-3-indolyl-beta -D-galactopyranoside (X-Gal) to monitor lacZ gene expression on the basis of blue/white color selection. Several cycles of filter cloning resulted in cell lineages in which lacZ gene expression alternated between the On and Off states in successive generations of progeny clones. The promoter regions of the M9-lacZ hybrid genes of individual progeny clones were amplified by PCR and sequenced. The only differences between the promoter regions of the blue and white colonies were in the number of GAA repeats. Clones that expressed lacZ had exactly 12 tandem copies of the GAA repeat. Clones that did not express lacZ invariably had either more than 12 (14 to 16) or fewer than 12 (5 to 11) GAA repeats. Southern analysis of M. gallisepticum chromosomal DNA confirmed that the phase-variable expression of the lacZ reporter gene was not caused by Tn4001 transposition. These data strongly indicate that changes in the length of the GAA repeat region are responsible for regulating M9/pMGA gene expression.


* Corresponding author. Mailing address: Department of Pathobiology, College of Veterinary Medicine, Auburn University, Auburn, AL 36849. Phone: (334) 844-4953. Fax: (334) 844-4955. E-mail: pananvs{at}vetmed.auburn.edu.


Infection and Immunity, February 2000, p. 871-876, Vol. 68, No. 2
0019-9567/00/$04.00+0
Copyright © 2000, American Society for Microbiology. All rights reserved.



This article has been cited by other articles:

  • Vasconcelos, A. T. R., Ferreira, H. B., Bizarro, C. V., Bonatto, S. L., Carvalho, M. O., Pinto, P. M., Almeida, D. F., Almeida, L. G. P., Almeida, R., Alves-Filho, L., Assuncao, E. N., Azevedo, V. A. C., Bogo, M. R., Brigido, M. M., Brocchi, M., Burity, H. A., Camargo, A. A., Camargo, S. S., Carepo, M. S., Carraro, D. M., de Mattos Cascardo, J. C., Castro, L. A., Cavalcanti, G., Chemale, G., Collevatti, R. G., Cunha, C. W., Dallagiovanna, B., Dambros, B. P., Dellagostin, O. A., Falcao, C., Fantinatti-Garboggini, F., Felipe, M. S. S., Fiorentin, L., Franco, G. R., Freitas, N. S. A., Frias, D., Grangeiro, T. B., Grisard, E. C., Guimaraes, C. T., Hungria, M., Jardim, S. N., Krieger, M. A., Laurino, J. P., Lima, L. F. A., Lopes, M. I., Loreto, E. L. S., Madeira, H. M. F., Manfio, G. P., Maranhao, A. Q., Martinkovics, C. T., Medeiros, S. R. B., Moreira, M. A. M., Neiva, M., Ramalho-Neto, C. E., Nicolas, M. F., Oliveira, S. C., Paixao, R. F. C., Pedrosa, F. O., Pena, S. D. J., Pereira, M., Pereira-Ferrari, L., Piffer, I., Pinto, L. S., Potrich, D. P., Salim, A. C. M., Santos, F. R., Schmitt, R., Schneider, M. P. C., Schrank, A., Schrank, I. S., Schuck, A. F., Seuanez, H. N., Silva, D. W., Silva, R., Silva, S. C., Soares, C. M. A., Souza, K. R. L., Souza, R. C., Staats, C. C., Steffens, M. B. R., Teixeira, S. M. R., Urmenyi, T. P., Vainstein, M. H., Zuccherato, L. W., Simpson, A. J. G., Zaha, A. (2005). Swine and Poultry Pathogens: the Complete Genome Sequences of Two Strains of Mycoplasma hyopneumoniae and a Strain of Mycoplasma synoviae. J. Bacteriol. 187: 5568-5577 [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]  
  • van der Woude, M. W., Baumler, A. J. (2004). Phase and Antigenic Variation in Bacteria. Clin. Microbiol. Rev. 17: 581-611 [Abstract] [Full Text]  
  • Napierala, M., Dere, R., Vetcher, A., Wells, R. D. (2004). Structure-dependent Recombination Hot Spot Activity of GAA{middle dot}TTC Sequences from Intron 1 of the Friedreich's Ataxia Gene. J. Biol. Chem. 279: 6444-6454 [Abstract] [Full Text]  
  • Papazisi, L., Gorton, T. S., Kutish, G., Markham, P. F., Browning, G. F., Nguyen, D. K., Swartzell, S., Madan, A., Mahairas, G., Geary, S. J. (2003). The complete genome sequence of the avian pathogen Mycoplasma gallisepticum strain Rlow. Microbiology 149: 2307-2316 [Abstract] [Full Text]  
  • Napierala, M., Parniewski, P., Pluciennik, A., Wells, R. D. (2002). Long CTG{middle dot}CAG Repeat Sequences Markedly Stimulate Intramolecular Recombination. J. Biol. Chem. 277: 34087-34100 [Abstract] [Full Text]  
  • Liu, L., Panangala, V. S., Dybvig, K. (2002). Trinucleotide GAA Repeats Dictate pMGA Gene Expression in Mycoplasma gallisepticum by Affecting Spacing between Flanking Regions. J. Bacteriol. 184: 1335-1339 [Abstract] [Full Text]  
  • Metzgar, D., Liu, L., Hansen, C., Dybvig, K., Wills, C. (2002). Domain-Level Differences in Microsatellite Distribution and Content Result from Different Relative Rates of Insertion and Deletion Mutations. Genome Res 12: 408-413 [Abstract] [Full Text]  
  • Teachman, A. M., French, C. T., Yu, H., Simmons, W. L., Dybvig, K. (2002). Gene Transfer in Mycoplasma pulmonis. J. Bacteriol. 184: 947-951 [Abstract] [Full Text]  
  • Shen, X., Gumulak, J., Yu, H., French, C. T., Zou, N., Dybvig, K. (2000). Gene Rearrangements in the vsa Locus of Mycoplasma pulmonis. J. Bacteriol. 182: 2900-2908 [Abstract] [Full Text]