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Proc Natl Acad Sci U S A. 1989 Sep; 86(17): 6656–6660.
PMCID: PMC297904

Negative transcriptional regulation in the Caulobacter flagellar hierarchy.


The Caulobacter crescentus flagellum is formed at a specific time in the cell cycle and its assembly requires the ordered expression of a large number of genes. These genes are controlled in a positive trans-acting hierarchy that reflects the order of assembly of the flagellum. Using plasmids carrying transcriptional fusions of either a neo or a lux reporter gene to the promoters of three flagellar genes representing different ranks in the hierarchy (the hook operon, a basal body gene flbN, and the flaO gene), we have measured the level of chimeric gene expression in 13 flagellar mutant backgrounds. Mutants in the hook operon or in basal body genes caused overproduction of both hook operon and basal body gene chimeric mRNAs, suggesting that negative regulation is superimposed on the positive trans-acting control for these early events in the flagellar hierarchy. Mutants in the structural genes and in genes involved in flagellar assembly had no effect on flaO expression, placing the flaO gene near the top of the hierarchy. However, flaO expression appears to be under negative control by two regulatory genes flaS and flaW. Negative control, as a response to the completion of specific steps in the assembly process, may be an important mechanism used by the cell to turn off flagellar gene expression once the gene product is no longer needed.

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Selected References

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  • Ely B, Croft RH, Gerardot CJ. Genetic mapping of genes required for motility in Caulobacter crescentus. Genetics. 1984 Nov;108(3):523–532. [PMC free article] [PubMed]
  • Ely B, Gerardot CJ, Fleming DL, Gomes SL, Frederikse P, Shapiro L. General nonchemotactic mutants of Caulobacter crescentus. Genetics. 1986 Nov;114(3):717–730. [PMC free article] [PubMed]
  • Hahnenberger KM, Shapiro L. Identification of a gene cluster involved in flagellar basal body biogenesis in Caulobacter crescentus. J Mol Biol. 1987 Mar 5;194(1):91–103. [PubMed]
  • Sheffery M, Newton A. Purification and characterization of a polyhook protein from Caulobacter crescentus. J Bacteriol. 1979 May;138(2):575–583. [PMC free article] [PubMed]
  • Driks A, Bryan R, Shapiro L, DeRosier DJ. The organization of the Caulobacter crescentus flagellar filament. J Mol Biol. 1989 Apr 20;206(4):627–636. [PubMed]
  • Johnson RC, Walsh MP, Ely B, Shapiro L. Flagellar hook and basal complex of Caulobacter crescentus. J Bacteriol. 1979 Jun;138(3):984–989. [PMC free article] [PubMed]
  • Wagenknecht T, DeRosier D, Shapiro L, Weissborn A. Three-dimensional reconstruction of the flagellar hook from Caulobacter crescentus. J Mol Biol. 1981 Sep 25;151(3):439–465. [PubMed]
  • Koyasu S, Asada M, Fukuda A, Okada Y. Sequential polymerization of flagellin A and flagellin B into Caulobacter flagella. J Mol Biol. 1981 Dec 5;153(2):471–475. [PubMed]
  • Weissborn A, Steinmann HM, Shapiro L. Characterization of the proteins of the Caulobacter crescentus flagellar filament. Peptide analysis and filament organization. J Biol Chem. 1982 Feb 25;257(4):2066–2074. [PubMed]
  • Shapiro L, Maizel JV., Jr Synthesis and structure of Caulobacter crescentus flagella. J Bacteriol. 1973 Jan;113(1):478–485. [PMC free article] [PubMed]
  • Osley MA, Sheffery M, Newton A. Regulation of flagellin synthesis in the cell cycle of caulobacter: dependence on DNA replication. Cell. 1977 Oct;12(2):393–400. [PubMed]
  • Lagenaur C, Agabian N. Caulobacter flagellar organelle: synthesis, compartmentation, and assembly. J Bacteriol. 1978 Sep;135(3):1062–1069. [PMC free article] [PubMed]
  • Agabian N, Evinger M, Parker G. Generation of asymmetry during development. Segregation of type-specific proteins in Caulobacter. J Cell Biol. 1979 Apr;81(1):123–136. [PMC free article] [PubMed]
  • Osley MA, Newton A. Temporal control of the cell cycle in Caulobacter crescentus: roles of DNA chain elongation and completion. J Mol Biol. 1980 Mar 25;138(1):109–128. [PubMed]
  • Sheffery M, Newton A. Regulation of periodic protein synthesis in the cell cycle: control of initiation and termination of flagellar gene expression. Cell. 1981 Apr;24(1):49–57. [PubMed]
  • Hahnenberger KM, Shapiro L. Organization and temporal expression of a flagellar basal body gene in Caulobacter crescentus. J Bacteriol. 1988 Sep;170(9):4119–4124. [PMC free article] [PubMed]
  • Loewy ZG, Bryan RA, Reuter SH, Shapiro L. Control of synthesis and positioning of a Caulobacter crescentus flagellar protein. Genes Dev. 1987 Aug;1(6):626–635. [PubMed]
  • Ohta N, Chen LS, Swanson E, Newton A. Transcriptional regulation of a periodically controlled flagellar gene operon in Caulobacter crescentus. J Mol Biol. 1985 Nov 5;186(1):107–115. [PubMed]
  • Champer R, Bryan R, Gomes SL, Purucker M, Shapiro L. Temporal and spatial control of flagellar and chemotaxis gene expression during Caulobacter cell differentiation. Cold Spring Harb Symp Quant Biol. 1985;50:831–840. [PubMed]
  • Champer R, Dingwall A, Shapiro L. Cascade regulation of Caulobacter flagellar and chemotaxis genes. J Mol Biol. 1987 Mar 5;194(1):71–80. [PubMed]
  • Chen LS, Mullin D, Newton A. Identification, nucleotide sequence, and control of developmentally regulated promoters in the hook operon region of Caulobacter crescentus. Proc Natl Acad Sci U S A. 1986 May;83(9):2860–2864. [PMC free article] [PubMed]
  • Minnich SA, Newton A. Promoter mapping and cell cycle regulation of flagellin gene transcription in Caulobacter crescentus. Proc Natl Acad Sci U S A. 1987 Mar;84(5):1142–1146. [PMC free article] [PubMed]
  • Evinger M, Agabian N. Envelope-associated nucleoid from Caulobacter crescentus stalked and swarmer cells. J Bacteriol. 1977 Oct;132(1):294–301. [PMC free article] [PubMed]
  • Johnson RC, Ely B. Analysis of nonmotile mutants of the dimorphic bacterium Caulobacter crescentus. J Bacteriol. 1979 Jan;137(1):627–634. [PMC free article] [PubMed]
  • Johnson RC, Ferber DM, Ely B. Synthesis and assembly of flagellar components by Caulobacter crescentus motility mutants. J Bacteriol. 1983 Jun;154(3):1137–1144. [PMC free article] [PubMed]
  • Contreras I, Shapiro L, Henry S. Membrane phospholipid composition of Caulobacter crescentus. J Bacteriol. 1978 Sep;135(3):1130–1136. [PMC free article] [PubMed]
  • Gomes SL, Shapiro L. Differential expression and positioning of chemotaxis methylation proteins in Caulobacter. J Mol Biol. 1984 Sep 25;178(3):551–568. [PubMed]
  • Bellofatto V, Shapiro L, Hodgson DA. Generation of a Tn5 promoter probe and its use in the study of gene expression in Caulobacter crescentus. Proc Natl Acad Sci U S A. 1984 Feb;81(4):1035–1039. [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. [PMC free article] [PubMed]
  • Hirooka T, Rogowsky PM, Kado CI. Characterization of the virE locus of Agrobacterium tumefaciens plasmid pTiC58. J Bacteriol. 1987 Apr;169(4):1529–1536. [PMC free article] [PubMed]
  • Mullin D, Minnich S, Chen LS, Newton A. A set of positively regulated flagellar gene promoters in Caulobacter crescentus with sequence homology to the nif gene promoters of Klebsiella pneumoniae. J Mol Biol. 1987 Jun 20;195(4):939–943. [PubMed]
  • Ohta N, Swanson E, Ely B, Newton A. Physical mapping and complementation analysis of transposon Tn5 mutations in Caulobacter crescentus: organization of transcriptional units in the hook gene cluster. J Bacteriol. 1984 Jun;158(3):897–904. [PMC free article] [PubMed]
  • Newton A, Ohta N, Ramakrishnan G, Mullin D, Raymond G. Genetic switching in the flagellar gene hierarchy of Caulobacter requires negative as well as positive regulation of transcription. Proc Natl Acad Sci U S A. 1989 Sep;86(17):6651–6655. [PMC free article] [PubMed]
  • Komeda Y. Fusions of flagellar operons to lactose genes on a mu lac bacteriophage. J Bacteriol. 1982 Apr;150(1):16–26. [PMC free article] [PubMed]
  • Komeda Y. Transcriptional control of flagellar genes in Escherichia coli K-12. J Bacteriol. 1986 Dec;168(3):1315–1318. [PMC free article] [PubMed]
  • Bryan R, Champer R, Gomes S, Ely B, Shapiro L. Separation of temporal control and trans-acting modulation of flagellin and chemotaxis genes in Caulobacter. Mol Gen Genet. 1987 Feb;206(2):300–306. [PubMed]

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