Skip to main content
NCBI home page
Proceedings of the National Academy of Sciences of the United States of America logoLink to Proceedings of the National Academy of Sciences of the United States of America
. 1989 May;86(10):3733–3737. doi: 10.1073/pnas.86.10.3733

Saturation mutagenesis of the octopine synthase enhancer: correlation of mutant phenotypes with binding of a nuclear protein factor.

K Singh 1, J G Tokuhisa 1, E S Dennis 1, W J Peacock 1
PMCID: PMC287214  PMID: 2726750

Abstract

A 16-base-pair palindrome from the Agrobacterium tumefaciens octopine synthase gene functions as a constitutive enhancer in plant protoplasts. Degenerate oligonucleotide mutagenesis provided single base substitutions at every position in the element and a number of multiple base substitutions. The effects of these changes were determined in transient expression assays with tobacco and maize protoplasts. The majority of single and double base changes had little effect on the activity of the octopine synthase enhancer, but nearly all mutants with more than two base changes had low to essentially no activity. There were five positions where particular single base changes resulted in a 4- to 10-fold loss in enhancer activity. The distribution of these positions within the palindrome was asymmetric. Single base deletions had essentially no activity, demonstrating that the octopine synthase enhancer cannot tolerate internal changes in spacing. We find a strong correlation between mutant phenotype and reduced binding of a protein factor, suggesting that the DNA-protein complex is responsible for the transcriptional enhancement; the functionally active form of the DNA-protein complex probably involves more than a single protein molecule. The mutants exhibit similar phenotypes in protoplasts of both tobacco and maize, implying conservation of the DNA-protein interactions of the ocs enhancer sequence in monocotyledonous and dicotyledonous plants.

Full text

PDF
3733

Images in this article

3736Image
on p.3736

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Baumruker T., Sturm R., Herr W. OBP100 binds remarkably degenerate octamer motifs through specific interactions with flanking sequences. Genes Dev. 1988 Nov;2(11):1400–1413. doi: 10.1101/gad.2.11.1400. [DOI] [PubMed] [Google Scholar]
  2. Chen W., Struhl K. Saturation mutagenesis of a yeast his3 "TATA element": genetic evidence for a specific TATA-binding protein. Proc Natl Acad Sci U S A. 1988 Apr;85(8):2691–2695. doi: 10.1073/pnas.85.8.2691. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. De Greve H., Dhaese P., Seurinck J., Lemmers M., Van Montagu M., Schell J. Nucleotide sequence and transcript map of the Agrobacterium tumefaciens Ti plasmid-encoded octopine synthase gene. J Mol Appl Genet. 1982;1(6):499–511. [PubMed] [Google Scholar]
  4. Derbyshire K. M., Salvo J. J., Grindley N. D. A simple and efficient procedure for saturation mutagenesis using mixed oligodeoxynucleotides. Gene. 1986;46(2-3):145–152. doi: 10.1016/0378-1119(86)90398-7. [DOI] [PubMed] [Google Scholar]
  5. Ellis J. G., Llewellyn D. J., Walker J. C., Dennis E. S., Peacock W. J. The ocs element: a 16 base pair palindrome essential for activity of the octopine synthase enhancer. EMBO J. 1987 Nov;6(11):3203–3208. doi: 10.1002/j.1460-2075.1987.tb02636.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. 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]
  7. Garner M. M., Revzin A. A gel electrophoresis method for quantifying the binding of proteins to specific DNA regions: application to components of the Escherichia coli lactose operon regulatory system. Nucleic Acids Res. 1981 Jul 10;9(13):3047–3060. doi: 10.1093/nar/9.13.3047. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Goodbourn S., Maniatis T. Overlapping positive and negative regulatory domains of the human beta-interferon gene. Proc Natl Acad Sci U S A. 1988 Mar;85(5):1447–1451. doi: 10.1073/pnas.85.5.1447. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Green P. J., Kay S. A., Chua N. H. Sequence-specific interactions of a pea nuclear factor with light-responsive elements upstream of the rbcS-3A gene. EMBO J. 1987 Sep;6(9):2543–2549. doi: 10.1002/j.1460-2075.1987.tb02542.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Hill D. E., Hope I. A., Macke J. P., Struhl K. Saturation mutagenesis of the yeast his3 regulatory site: requirements for transcriptional induction and for binding by GCN4 activator protein. Science. 1986 Oct 24;234(4775):451–457. doi: 10.1126/science.3532321. [DOI] [PubMed] [Google Scholar]
  11. Hinnebusch A. G. Mechanisms of gene regulation in the general control of amino acid biosynthesis in Saccharomyces cerevisiae. Microbiol Rev. 1988 Jun;52(2):248–273. doi: 10.1128/mr.52.2.248-273.1988. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Hope I. A., Struhl K. GCN4 protein, synthesized in vitro, binds HIS3 regulatory sequences: implications for general control of amino acid biosynthetic genes in yeast. Cell. 1985 Nov;43(1):177–188. doi: 10.1016/0092-8674(85)90022-4. [DOI] [PubMed] [Google Scholar]
  13. Jefferson R. A., Kavanagh T. A., Bevan M. W. GUS fusions: beta-glucuronidase as a sensitive and versatile gene fusion marker in higher plants. EMBO J. 1987 Dec 20;6(13):3901–3907. doi: 10.1002/j.1460-2075.1987.tb02730.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Jones N. C., Rigby P. W., Ziff E. B. Trans-acting protein factors and the regulation of eukaryotic transcription: lessons from studies on DNA tumor viruses. Genes Dev. 1988 Mar;2(3):267–281. doi: 10.1101/gad.2.3.267. [DOI] [PubMed] [Google Scholar]
  15. Jones R. H., Moreno S., Nurse P., Jones N. C. Expression of the SV40 promoter in fission yeast: identification and characterization of an AP-1-like factor. Cell. 1988 May 20;53(4):659–667. doi: 10.1016/0092-8674(88)90581-8. [DOI] [PubMed] [Google Scholar]
  16. 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]
  17. Llewellyn D. J., Finnegan E. J., Ellis J. G., Dennis E. S., Peacock W. J. Structure and expression of an alcohol dehydrogenase 1 gene from Pisum sativum (cv. "Greenfeast"). J Mol Biol. 1987 May 5;195(1):115–123. doi: 10.1016/0022-2836(87)90331-7. [DOI] [PubMed] [Google Scholar]
  18. Maniatis T., Goodbourn S., Fischer J. A. Regulation of inducible and tissue-specific gene expression. Science. 1987 Jun 5;236(4806):1237–1245. doi: 10.1126/science.3296191. [DOI] [PubMed] [Google Scholar]
  19. Myers R. M., Tilly K., Maniatis T. Fine structure genetic analysis of a beta-globin promoter. Science. 1986 May 2;232(4750):613–618. doi: 10.1126/science.3457470. [DOI] [PubMed] [Google Scholar]
  20. Ptashne M. How eukaryotic transcriptional activators work. Nature. 1988 Oct 20;335(6192):683–689. doi: 10.1038/335683a0. [DOI] [PubMed] [Google Scholar]
  21. Sanger F., Nicklen S., Coulson A. R. DNA sequencing with chain-terminating inhibitors. Proc Natl Acad Sci U S A. 1977 Dec;74(12):5463–5467. doi: 10.1073/pnas.74.12.5463. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Schleif R. DNA binding by proteins. Science. 1988 Sep 2;241(4870):1182–1187. doi: 10.1126/science.2842864. [DOI] [PubMed] [Google Scholar]
  23. Spector T. Refinement of the coomassie blue method of protein quantitation. A simple and linear spectrophotometric assay for less than or equal to 0.5 to 50 microgram of protein. Anal Biochem. 1978 May;86(1):142–146. doi: 10.1016/0003-2697(78)90327-5. [DOI] [PubMed] [Google Scholar]
  24. Struhl K. Promoters, activator proteins, and the mechanism of transcriptional initiation in yeast. Cell. 1987 May 8;49(3):295–297. doi: 10.1016/0092-8674(87)90277-7. [DOI] [PubMed] [Google Scholar]
  25. Walker J. C., Howard E. A., Dennis E. S., Peacock W. J. DNA sequences required for anaerobic expression of the maize alcohol dehydrogenase 1 gene. Proc Natl Acad Sci U S A. 1987 Oct;84(19):6624–6628. doi: 10.1073/pnas.84.19.6624. [DOI] [PMC free article] [PubMed] [Google Scholar]
  26. Willmitzer L., Wagner K. G. The isolation of nuclei from tissue-cultured plant cells. Exp Cell Res. 1981 Sep;135(1):69–77. doi: 10.1016/0014-4827(81)90300-1. [DOI] [PubMed] [Google Scholar]
  27. Wissmann A., Meier I., Hillen W. Saturation mutagenesis of the Tn10-encoded tet operator O1. Identification of base-pairs involved in Tet repressor recognition. J Mol Biol. 1988 Aug 5;202(3):397–406. doi: 10.1016/0022-2836(88)90273-2. [DOI] [PubMed] [Google Scholar]

Articles from Proceedings of the National Academy of Sciences of the United States of America are provided here courtesy of National Academy of Sciences

RESOURCES