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Escherichia coli cytotoxic necrotizing factor 1 blocks cell cycle G2/M transition in uroepithelial cells

Loredana Falzano1, Perla Filippini, Sara Travaglione

  • 1Department of Drug Research and Evaluation, Viale Regina Elena 299 00161, Rome, Italy.

Infection and Immunity
|June 23, 2006
PubMed

Insights

Cytotoxic necrotizing factor 1 (CNF1) from E. coli blocks uroepithelial cell cycle progression. This bacterial toxin disrupts cell division by affecting Rho GTPases and cyclin B1, impacting E. coli pathogenicity.

Area of Science:

  • Microbiology
  • Cell Biology
  • Toxicology

Background:

  • Bacterial toxins increasingly target eukaryotic cell cycle machinery.
  • Uropathogenic *Escherichia coli* (UPEC) produces cytotoxic necrotizing factor 1 (CNF1).

Purpose of the Study:

  • To investigate CNF1's effect on the uroepithelial cell cycle.
  • To elucidate the role of Rho GTPases in CNF1-mediated cell cycle disruption.

Main Methods:

  • Cell cycle analysis of T24 uroepithelial cells treated with CNF1.
  • Assessment of cyclin B1 localization and expression.
  • Investigation of Rho GTPase family activation.

Main Results:

  • CNF1 blocks G2/M cell cycle transition in T24 cells.
  • CNF1 sequesters cyclin B1 in the cytoplasm and reduces its expression.
  • CNF1 permanently activates Rho family GTPases.

Conclusions:

  • CNF1 disrupts uroepithelial cell cycle progression by interfering with cyclin B1 regulation.
  • Rho GTPase activation is implicated in CNF1-induced cell cycle deregulation.
  • CNF1's impact on cell cycle offers insights into UPEC pathogenicity.

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