Skip to main content
Journal of Bacteriology logoLink to Journal of Bacteriology
. 1984 Oct;160(1):192–198. doi: 10.1128/jb.160.1.192-198.1984

Regulation of the F-factor pif operon: pifO, a site required in cis for autoregulation, titrates the pifC product in trans.

J F Miller, M H Malamy
PMCID: PMC214699  PMID: 6090412

Abstract

F factor pifC, pifA, and pifB gene expression is subject to negative regulation by the product of the pifC locus (J.F. Miller and M. H. Malamy, J. Bacteriol. 156:338-347, 1983). In this paper, we describe the properties of a new regulatory site in the pif region, pifO, which is required in cis for autoregulation of pif gene expression. Spontaneous pifO mutations were isolated that allow expression of a pifC-lacZ protein fusion in the presence of pifC product in trans. Recombination of these pifO mutations onto F'lac results in increased pifA and pifB activity. Thus, a single regulatory element, pifO, regulates pifC, pifA, and pifB expression in cis. The presence of multiple copies of a fragment from the pif region carrying wild-type pifO sequences (F coordinates 42.9 to 42.43 kilobases) in trans to F'lac results in an increase in pifA and pifB activity as measured by inhibition of T7 plating. When the pifO mutations are recombined onto a plasmid carrying pifO, the resulting recombinants are greatly decreased in the ability to increase F'lac pif expression. These results suggest that increased F'lac pifA and pifB expression caused by pifO sequences in trans is a consequence of titration of pifC product and derepression of the pif operon.

Full text

PDF
192

Selected References

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

  1. Blumberg D. D., Mabie C. T., Malamy M. H. T7 protein synthesis in F-factor-containing cells: evidence for an episomally induced impairment of translation and relation to an alteration in membrane permeability. J Virol. 1975 Jan;17(1):94–105. doi: 10.1128/jvi.17.1.94-105.1976. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Bogosian G., Somerville R. L. Analysis in vivo of factors affecting the control of transcription initiation at promoters containing target sites for trp repressor. Mol Gen Genet. 1984;193(1):110–118. doi: 10.1007/BF00327423. [DOI] [PubMed] [Google Scholar]
  3. Casadaban M. J., Chou J., Cohen S. N. In vitro gene fusions that join an enzymatically active beta-galactosidase segment to amino-terminal fragments of exogenous proteins: Escherichia coli plasmid vectors for the detection and cloning of translational initiation signals. J Bacteriol. 1980 Aug;143(2):971–980. doi: 10.1128/jb.143.2.971-980.1980. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Eichenlaub R., Figurski D., Helinski D. R. Bidirection replication from a unique origin in a mini-F plasmid. Proc Natl Acad Sci U S A. 1977 Mar;74(3):1138–1141. doi: 10.1073/pnas.74.3.1138. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Gilbert W., Müller-Hill B. Isolation of the lac repressor. Proc Natl Acad Sci U S A. 1966 Dec;56(6):1891–1898. doi: 10.1073/pnas.56.6.1891. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Hershfield V., Boyer H. W., Yanofsky C., Lovett M. A., Helinski D. R. Plasmid ColEl as a molecular vehicle for cloning and amplification of DNA. Proc Natl Acad Sci U S A. 1974 Sep;71(9):3455–3459. doi: 10.1073/pnas.71.9.3455. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Heyneker H. L., Shine J., Goodman H. M., Boyer H. W., Rosenberg J., Dickerson R. E., Narang S. A., Itakura K., Lin S., Riggs A. D. Synthetic lac operator DNA is functional in vivo. Nature. 1976 Oct 28;263(5580):748–752. doi: 10.1038/263748a0. [DOI] [PubMed] [Google Scholar]
  8. Kilbane J. J., Malamy M. H. F factor mobilization of non-conjugative chimeric plasmids in Escherichia coli: general mechanisms and a role for site-specific recA-independent recombination at orV1. J Mol Biol. 1980 Oct 15;143(1):73–93. doi: 10.1016/0022-2836(80)90125-4. [DOI] [PubMed] [Google Scholar]
  9. MAEKELAE O., MAEKELAE P. H., SOIKKELI S. SEX-SPECIFICITY OF THE BACTERIOPHAGE T7. Ann Med Exp Biol Fenn. 1964;42:188–195. [PubMed] [Google Scholar]
  10. Marians K. J., Wu R., Stawinski J., Hozumi T., Narang S. A. Cloned synthetic lac operator DNA is biologically active. Nature. 1976 Oct 28;263(5580):744–748. doi: 10.1038/263744a0. [DOI] [PubMed] [Google Scholar]
  11. Miller J. F., Malamy M. H. Identification of the pifC gene and its role in negative control of F factor pif gene expression. J Bacteriol. 1983 Oct;156(1):338–347. doi: 10.1128/jb.156.1.338-347.1983. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Morrison T. G., Malamy M. H. Comparisons of F factors and R factors: existence of independent regulation groups in F factors. J Bacteriol. 1970 Jul;103(1):81–88. doi: 10.1128/jb.103.1.81-88.1970. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Morrison T. G., Malamy M. H. T7 translational control mechanisms and their inhibiton by F factors. Nat New Biol. 1971 May 12;231(19):37–41. doi: 10.1038/newbio231037a0. [DOI] [PubMed] [Google Scholar]
  14. Müller-Hill B., Crapo L., Gilbert W. Mutants that make more lac repressor. Proc Natl Acad Sci U S A. 1968 Apr;59(4):1259–1264. doi: 10.1073/pnas.59.4.1259. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Rotman G. S., Cooney R., Malamy M. H. Cloning of the pif region of the F sex factor and identification of a pif protein product. J Bacteriol. 1983 Jul;155(1):254–264. doi: 10.1128/jb.155.1.254-264.1983. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Sadler J. R., Tecklenburg M., Betz J. L., Goeddel D. V., Yansura D. G., Caruthers M. H. Cloning of chemically synthesized lactose operators. Gene. 1977 Jul;1(5-6):305–321. doi: 10.1016/0378-1119(77)90036-1. [DOI] [PubMed] [Google Scholar]
  17. Smith T. F., Sadler J. R. The nature of lactose operator constitive mutations. J Mol Biol. 1971 Jul 28;59(2):273–305. doi: 10.1016/0022-2836(71)90051-9. [DOI] [PubMed] [Google Scholar]
  18. Søgaard-Andersen L., Rokeach L. A., Molin S. Regulated expression of a gene important for replication of plasmid F in E. coli. EMBO J. 1984 Feb;3(2):257–262. doi: 10.1002/j.1460-2075.1984.tb01794.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Tanimoto K., Iino T. Transfer inhibition of RP4 by F factor. Mol Gen Genet. 1983;192(1-2):104–109. doi: 10.1007/BF00327654. [DOI] [PubMed] [Google Scholar]
  20. Timmis K., Cabello F., Cohen S. N. Cloning, isolation, and characterization of replication regions of complex plasmid genomes. Proc Natl Acad Sci U S A. 1975 Jun;72(6):2242–2246. doi: 10.1073/pnas.72.6.2242. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Journal of Bacteriology are provided here courtesy of American Society for Microbiology (ASM)

RESOURCES