• Search Research Projects
  • Search Researchers
  • How to Use
  1. Back to previous page

Analysis of transcriptional activation of the replication origin of Escherichia coli for initation of chromosome replication

Research Project

Project/Area Number 07640826
Research Category

Grant-in-Aid for Scientific Research (C)

Allocation TypeSingle-year Grants
Section一般
Research Field 遺伝
Research InstitutionNational Insitute of Health

Principal Investigator

SAKAKIBARA Yoshimasa  National Institute of Health, Department of Biochemistry and Cellular Biology, Section chief., 細胞化学部, 室長 (10072927)

Co-Investigator(Kenkyū-buntansha) YAMAKAWA Yoshio  National Institute of Health, Department of Biochemistry and Cellular Biology, S, 細胞化学部, 室長 (50100102)
Project Period (FY) 1995 – 1996
Project Status Completed (Fiscal Year 1996)
Budget Amount *help
¥2,200,000 (Direct Cost: ¥2,200,000)
Fiscal Year 1996: ¥1,000,000 (Direct Cost: ¥1,000,000)
Fiscal Year 1995: ¥1,200,000 (Direct Cost: ¥1,200,000)
KeywordsEscherichia coli / Replication initiation / RNA polymerase / Rifampicin / dnaR / dnaA / rpe / Phosphoribosylpyrophosphate synthetase / rpoB / リブロース燐酸エピメラーゼ / リボース燐酸キナーゼ / 転写による活性化
Research Abstract

Initiation of replication of Escherichia coli chromosome is rendered tempertre-sensitive by the dnaR130 mutation in the prs gene that encodes phosphoribosylpyrophosphate synthetase. The thermosensitivity of the danR mtant is supperssed by some rifampicin resistance mutations in rpoB,the gene for the beta subunit of RNA polymerase. Some of the rpoB mutations can suppress the thermosensitivity of ecrtain dnaA mutants in initiation of replication. The rpoB-mediated suppression of the dnaA or dnaR defect requires the dnaA or dnaR product to be functional in response to the rpoB mutation. Taking together with the previous finding that the dnaR defect can be suppressed by some dnaA mutations, it is likey that the dnaR product functions cooperatively with the dnaA product in a transcriptional event required for initiation of chromosome replication. The dnaR mutant exposed to the nonpermissive temperature is capable ofthermoresistant DNA synthesis in the presence of rifampicin (Rif), which inh … More ibits initiation of replication in dnaR^+ cells. The DNA synthesis elicited by Rif is initiated from oriC in a dnaA-dependent manner. It has been shown that RNA polymerase bound to Rif before attaching to template DNA loses the transcription activity while the transcibing polymerase bound to the drug continues transcription beyond some attenuators or terminators. Therefore, Rif-induced replication in the dnaR mutant seems to be mediated by particular RNA polymerase molecules that could contine transcription after Rif binding, probably through read-through transcription within or around the oriC region. As an extragenic suppressor for the dnaR mutant, the rpe gene that encodes ribulose-5-phosphate epimerase has been identified. This gene is dispensable for cell growth. Disruption of the rpe gene reverses the thermosensitivity of the dnaR mutant in DNA synthesis and cell growth. On the other hand, the rpe mutation abolishes or diminishes the abilities of certain dnaA and dnaR mutant alleles to complement dnaA and dnaR defects by different alleles, respectively. Thus, the rpe product is involved in the functions of both dnaA and dnaR products for initiation of replication of the bacterial chromosome. Less

Report

(3 results)
  • 1996 Annual Research Report   Final Research Report Summary
  • 1995 Annual Research Report
  • Research Products

    (7 results)

All Other

All Publications (7 results)

  • [Publications] Yoshimasa Sakakibara: "Rifampin-induced initiation of chromosome replication in dnaR‐deficient Escherichia coli cells" Journal of Bacteriology. 178・5. 1242-1247 (1996)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1996 Final Research Report Summary
  • [Publications] Yoshimasa Sakakibara: "Involvement of the ribulosephosphate epimerase gene in the dnaA and dnaR functions for initiation of chromosome replication in Escherichia coli" Molecular Microbacteriology. (in press). (1997)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1996 Final Research Report Summary
  • [Publications] Yoshimasa Sakakibara: "Rifampin-induced initiation of chromosome replication in dnaR-deficient Escherichia coli cells." Jounal of Bacteriology. 178. 1242-1247 (1996)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1996 Final Research Report Summary
  • [Publications] Yoshimasa Sakakibara: "Involvement of the riblosephosphate epimerase gene in the dnaA and danR functions for initiation of chromosome replication in Escherichia coli." Molecular Microbiology. (in press). (1997)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1996 Final Research Report Summary
  • [Publications] Yoshimasa Sakakibara: "Rifampin-induced initiation of chromosome replication in dnaR-deficient Escherichia coli cells" Journal of Bacteriology. 178・5. 1242-1247 (1996)

    • Related Report
      1996 Annual Research Report
  • [Publications] Yoshimasa Sakakibara: "Involvement of the ribulosephosphate epimerase gene in the dnaA and dnaR functions for initiation of chromosome replication in Escherichia coli" Molecular Microbacteriology. (in press). (1997)

    • Related Report
      1996 Annual Research Report
  • [Publications] Yoshimasa SAKAKIBARA: "Rifampin-induced initiation of chromosome replicaion in dnaR-deficient Escherichia coli cells" Journal of Bacteriology. 178. Mar-5 (1996)

    • Related Report
      1995 Annual Research Report

URL: 

Published: 1995-04-01   Modified: 2016-04-21  

Information User Guide FAQ News Terms of Use Attribution of KAKENHI

Powered by NII kakenhi