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-
-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]