Abstract
In Agrobacterium tumefaciens, a cis-active 24-base-pair sequence adjacent to the right border of the T-DNA, called overdrive, stimulates tumor formation by increasing the level of T-DNA processing. Recent results from our laboratory have suggested that the virC operon which enhances T-DNA processing probably does so because the VirC1 protein interacts with overdrive (N. Toro, A. Datta, M. Yanofsky, and E. W. Nester, Proc. Natl. Acad. Sci. USA 85:8558-8562, 1988). We report here the purification of the VirC1 protein from cells of Escherichia coli harboring a plasmid containing the coding sequences of the virC locus of the octopine Ti plasmid. By gel mobility shift and DNase I footprinting assays, we showed that this purified virC1 gene product binds to overdrive but not to the right border of T-DNA.
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- Albright L. M., Yanofsky M. F., Leroux B., Ma D. Q., Nester E. W. Processing of the T-DNA of Agrobacterium tumefaciens generates border nicks and linear, single-stranded T-DNA. J Bacteriol. 1987 Mar;169(3):1046–1055. doi: 10.1128/jb.169.3.1046-1055.1987. [DOI] [PMC free article] [PubMed] [Google Scholar]
- De Vos G., Zambryski P. Expression of Agrobacterium nopaline-specific VirD1, VirD2, and VirC1 proteins and their requirement for T-strand production in E. coli. Mol Plant Microbe Interact. 1989 Mar-Apr;2(2):43–52. doi: 10.1094/mpmi-2-043. [DOI] [PubMed] [Google Scholar]
- Fried M., Crothers D. M. Equilibria and kinetics of lac repressor-operator interactions by polyacrylamide gel electrophoresis. Nucleic Acids Res. 1981 Dec 11;9(23):6505–6525. doi: 10.1093/nar/9.23.6505. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kadonaga J. T., Tjian R. Affinity purification of sequence-specific DNA binding proteins. Proc Natl Acad Sci U S A. 1986 Aug;83(16):5889–5893. doi: 10.1073/pnas.83.16.5889. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Laemmli U. K. Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature. 1970 Aug 15;227(5259):680–685. doi: 10.1038/227680a0. [DOI] [PubMed] [Google Scholar]
- Lee W., Mitchell P., Tjian R. Purified transcription factor AP-1 interacts with TPA-inducible enhancer elements. Cell. 1987 Jun 19;49(6):741–752. doi: 10.1016/0092-8674(87)90612-x. [DOI] [PubMed] [Google Scholar]
- Maxam A. M., Gilbert W. Sequencing end-labeled DNA with base-specific chemical cleavages. Methods Enzymol. 1980;65(1):499–560. doi: 10.1016/s0076-6879(80)65059-9. [DOI] [PubMed] [Google Scholar]
- Peralta E. G., Hellmiss R., Ream W. Overdrive, a T-DNA transmission enhancer on the A. tumefaciens tumour-inducing plasmid. EMBO J. 1986 Jun;5(6):1137–1142. doi: 10.1002/j.1460-2075.1986.tb04338.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Peralta E. G., Ream L. W. T-DNA border sequences required for crown gall tumorigenesis. Proc Natl Acad Sci U S A. 1985 Aug;82(15):5112–5116. doi: 10.1073/pnas.82.15.5112. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Stachel S. E., An G., Flores C., Nester E. W. A Tn3 lacZ transposon for the random generation of beta-galactosidase gene fusions: application to the analysis of gene expression in Agrobacterium. EMBO J. 1985 Apr;4(4):891–898. doi: 10.1002/j.1460-2075.1985.tb03715.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Stachel S. E., Nester E. W. The genetic and transcriptional organization of the vir region of the A6 Ti plasmid of Agrobacterium tumefaciens. EMBO J. 1986 Jul;5(7):1445–1454. doi: 10.1002/j.1460-2075.1986.tb04381.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Stachel S. E., Zambryski P. C. 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. doi: 10.1016/0092-8674(86)90653-7. [DOI] [PubMed] [Google Scholar]
- Toro N., Datta A., Yanofsky M., Nester E. Role of the overdrive sequence in T-DNA border cleavage in Agrobacterium. Proc Natl Acad Sci U S A. 1988 Nov;85(22):8558–8562. doi: 10.1073/pnas.85.22.8558. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Towbin H., Staehelin T., Gordon J. Electrophoretic transfer of proteins from polyacrylamide gels to nitrocellulose sheets: procedure and some applications. Proc Natl Acad Sci U S A. 1979 Sep;76(9):4350–4354. doi: 10.1073/pnas.76.9.4350. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Winans S. C., Ebert P. R., Stachel S. E., Gordon M. P., Nester E. W. 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. doi: 10.1073/pnas.83.21.8278. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Yadav N. S., Vanderleyden J., Bennett D. R., Barnes W. M., Chilton M. D. Short direct repeats flank the T-DNA on a nopaline Ti plasmid. Proc Natl Acad Sci U S A. 1982 Oct;79(20):6322–6326. doi: 10.1073/pnas.79.20.6322. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Yanofsky M. F., Nester E. W. Molecular characterization of a host-range-determining locus from Agrobacterium tumefaciens. J Bacteriol. 1986 Oct;168(1):244–250. doi: 10.1128/jb.168.1.244-250.1986. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Yanofsky M. F., Porter S. G., Young C., Albright L. M., Gordon M. P., Nester E. W. The virD operon of Agrobacterium tumefaciens encodes a site-specific endonuclease. Cell. 1986 Nov 7;47(3):471–477. doi: 10.1016/0092-8674(86)90604-5. [DOI] [PubMed] [Google Scholar]