A molecular mechanism for the repression of transcription by the H-NS protein.

Sylvie Rimsky (1) , F. Zuber (2) , Malcolm Buckle (1) , Henri Buc (2)

1 LBPA - Laboratoire de Biologie et de Pharmacologie Appliquée
2 Physicochimie des Macromolecules Biologiques

The H-NS protein is a major component of the bacterial nucleoid and plays a crucial role in the global gene regulation of enteric bacteria. Although H-NS does not exhibit a high DNA sequence specificity, a number of H-NS-responsive promoters have been shown to contain regions of intrinsic DNA curvature located either upstream or downstream of the transcription start point. We have studied H-NS binding to DNA and in vitro transcriptional regulation by H-NS at several synthetic promoters with or without curved sequences inserted upstream of the Pribnow box. We show how such inserts determine the final organization of H-NS-containing nucleoprotein complexes and how this affects transcription. We refine a two-step mechanism for the constitution of H-NS assemblies that are efficient in regulation.

Domaines: Biochimie, Biologie Moléculaire

Sylvie Rimsky, F. Zuber, Malcolm Buckle, Henri Buc. A molecular mechanism for the repression of transcription by the H-NS protein.. Molecular Microbiology, 2001, 42 (5), pp.1311-23. ⟨10.1046/j.1365-2958.2001.02706.x⟩. ⟨hal-00277533⟩