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Nucleic Acids Res. 1990 December 11; 18(23): 6909–6913.
PMCID: PMC332749

Characterization of the VirG binding site of Agrobacterium tumefaciens.


Expression of Agrobacterium tumefaciens virulence (vir) genes is dependent on the presence of a conserved 'vir box' sequence in their 5' nontranscribed regions. The location and number of these sequences vary considerably in different vir genes. Site-directed mutagenesis was used to identify the functional vir box(es) of virB, virC and virD. For virB expression both vir box B1 and B2 are required but only the vir box B1 is absolutely essential. Of the five vir boxes of virC and virD two are required for virC expression while only one vir box is required for virD expression. To investigate the minimum sequences necessary for vir gene induction a deletion derivative of virE that lacks the vir box region was used. This mutant is not induced by acetosyringone. The inducibility of this promoter was restored when a synthetic deoxyoligonucleotide dGTTTCAATTGAAAC was introduced at a location analogous to that of the wild type vir box sequence. Mutational analysis indicate that the functional vir box sequence is 14 residues in length, contains a dyad symmetry and has the consensus sequence d ryTncAaTTGnAaY [corrected] (r = purine, y = pyrimidine).

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Selected References

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  • Jin S, Roitsch T, Ankenbauer RG, Gordon MP, Nester EW. The VirA protein of Agrobacterium tumefaciens is autophosphorylated and is essential for vir gene regulation. J Bacteriol. 1990 Feb;172(2):525–530. [PMC free article] [PubMed]
  • Huang Y, Morel P, Powell B, Kado CI. VirA, a coregulator of Ti-specified virulence genes, is phosphorylated in vitro. J Bacteriol. 1990 Feb;172(2):1142–1144. [PMC free article] [PubMed]
  • Jin SG, Prusti RK, Roitsch T, Ankenbauer RG, Nester EW. Phosphorylation of the VirG protein of Agrobacterium tumefaciens by the autophosphorylated VirA protein: essential role in biological activity of VirG. J Bacteriol. 1990 Sep;172(9):4945–4950. [PMC free article] [PubMed]
  • Jin SG, Roitsch T, Christie PJ, Nester EW. The regulatory VirG protein specifically binds to a cis-acting regulatory sequence involved in transcriptional activation of Agrobacterium tumefaciens virulence genes. J Bacteriol. 1990 Feb;172(2):531–537. [PMC free article] [PubMed]
  • Pazour GJ, Das A. virG, an Agrobacterium tumefaciens transcriptional activator, initiates translation at a UUG codon and is a sequence-specific DNA-binding protein. J Bacteriol. 1990 Mar;172(3):1241–1249. [PMC free article] [PubMed]
  • Das A, Pazour GJ. Delineation of the regulatory region sequences of Agrobacterium tumefaciens virB operon. Nucleic Acids Res. 1989 Jun 26;17(12):4541–4550. [PMC free article] [PubMed]
  • Steck TR, Morel P, Kado CI. Vir box sequences in Agrobacterium tumefaciens pTiC58 and A6. Nucleic Acids Res. 1988 Sep 12;16(17):8736–8736. [PMC free article] [PubMed]
  • Winans SC. Transcriptional induction of an Agrobacterium regulatory gene at tandem promoters by plant-released phenolic compounds, phosphate starvation, and acidic growth media. J Bacteriol. 1990 May;172(5):2433–2438. [PMC free article] [PubMed]
  • Aoyama T, Takanami M, Oka A. Signal structure for transcriptional activation in the upstream regions of virulence genes on the hairy-root-inducing plasmid A4. Nucleic Acids Res. 1989 Nov 11;17(21):8711–8725. [PMC free article] [PubMed]
  • Vieira J, Messing J. Production of single-stranded plasmid DNA. Methods Enzymol. 1987;153:3–11. [PubMed]
  • Jayaswal RK, Veluthambi K, Gelvin SB, Slightom JL. Double-stranded cleavage of T-DNA and generation of single-stranded T-DNA molecules in Escherichia coli by a virD-encoded border-specific endonuclease from Agrobacterium tumefaciens. J Bacteriol. 1987 Nov;169(11):5035–5045. [PMC free article] [PubMed]
  • Kunkel TA. Rapid and efficient site-specific mutagenesis without phenotypic selection. Proc Natl Acad Sci U S A. 1985 Jan;82(2):488–492. [PubMed]
  • Sanger F, Nicklen S, Coulson AR. DNA sequencing with chain-terminating inhibitors. Proc Natl Acad Sci U S A. 1977 Dec;74(12):5463–5467. [PubMed]
  • Das A, Stachel S, Ebert P, Allenza P, Montoya A, Nester E. Promoters of Agrobacterium tumefaciens Ti-plasmid virulence genes. Nucleic Acids Res. 1986 Feb 11;14(3):1355–1364. [PMC free article] [PubMed]
  • Winans SC, Allenza P, Stachel SE, McBride KE, Nester EW. Characterization of the virE operon of the Agrobacterium Ti plasmid pTiA6. Nucleic Acids Res. 1987 Jan 26;15(2):825–837. [PMC free article] [PubMed]
  • Ditta G, Stanfield S, Corbin D, Helinski DR. Broad host range DNA cloning system for gram-negative bacteria: construction of a gene bank of Rhizobium meliloti. Proc Natl Acad Sci U S A. 1980 Dec;77(12):7347–7351. [PubMed]
  • Chilton MD, Currier TC, Farrand SK, Bendich AJ, Gordon MP, Nester EW. Agrobacterium tumefaciens DNA and PS8 bacteriophage DNA not detected in crown gall tumors. Proc Natl Acad Sci U S A. 1974 Sep;71(9):3672–3676. [PubMed]
  • Close TJ, Rogowsky PM, Kado CI, Winans SC, Yanofsky MF, Nester EW. Dual control of Agrobacterium tumefaciens Ti plasmid virulence genes. J Bacteriol. 1987 Nov;169(11):5113–5118. [PMC free article] [PubMed]
  • Schleif R. DNA binding by proteins. Science. 1988 Sep 2;241(4870):1182–1187. [PubMed]
  • Aoyama T, Oka A. A common mechanism of transcriptional activation by the three positive regulators, VirG, PhoB, and OmpR. FEBS Lett. 1990 Apr 9;263(1):1–4. [PubMed]
  • Maeda S, Mizuno T. Evidence for multiple OmpR-binding sites in the upstream activation sequence of the ompC promoter in Escherichia coli: a single OmpR-binding site is capable of activating the promoter. J Bacteriol. 1990 Jan;172(1):501–503. [PMC free article] [PubMed]
  • Maeda S, Ozawa Y, Mizuno T, Mizushima S. Stereospecific positioning of the cis-acting sequence with respect to the canonical promoter is required for activation of the ompC gene by a positive regulator, OmpR, in Escherichia coli. J Mol Biol. 1988 Aug 5;202(3):433–441. [PubMed]
  • Stachel SE, Zambryski PC. virA and virG control the plant-induced activation of the T-DNA transfer process of A. tumefaciens. Cell. 1986 Aug 1;46(3):325–333. [PubMed]
  • Rogowsky PM, Close TJ, Chimera JA, Shaw JJ, Kado CI. Regulation of the vir genes of Agrobacterium tumefaciens plasmid pTiC58. J Bacteriol. 1987 Nov;169(11):5101–5112. [PMC free article] [PubMed]
  • Winans SC, Kerstetter RA, Nester EW. Transcriptional regulation of the virA and virG genes of Agrobacterium tumefaciens. J Bacteriol. 1988 Sep;170(9):4047–4054. [PMC free article] [PubMed]
  • Winans SC, Ebert PR, Stachel SE, Gordon MP, Nester EW. A gene essential for Agrobacterium virulence is homologous to a family of positive regulatory loci. Proc Natl Acad Sci U S A. 1986 Nov;83(21):8278–8282. [PubMed]
  • Leroux B, Yanofsky MF, Winans SC, Ward JE, Ziegler SF, Nester EW. Characterization of the virA locus of Agrobacterium tumefaciens: a transcriptional regulator and host range determinant. EMBO J. 1987 Apr;6(4):849–856. [PubMed]
  • Ronson CW, Nixon BT, Ausubel FM. Conserved domains in bacterial regulatory proteins that respond to environmental stimuli. Cell. 1987 Jun 5;49(5):579–581. [PubMed]
  • Stock JB, Ninfa AJ, Stock AM. Protein phosphorylation and regulation of adaptive responses in bacteria. Microbiol Rev. 1989 Dec;53(4):450–490. [PMC free article] [PubMed]

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