In prokaryotes, the role of nucleoid-associated proteins in bacterial
physiology remains largely unknown. H-NS has been initially isolated
as a RNA polymerase associated factor. It is a polyanion binding protein
that may have several regulatory targets
Protein profiles (Proteome analysis) and
RNA expression profiles (Transcriptome
analysis) of wild-type and hns strains were compared in
Escherichia coli (11)
The expression of approximately 5% of the genes (Table
1) and/or the accumulation of the corresponding proteins are directly
or indirectly altered in the mutant strain. About 1/5 of these genes
encode proteins involved in transcription and translation, in particular
many regulators. This suggests that H-NS is located at a high level
in the hierarchy of regulation.(Figure 4)
One third of these genes are known or were predicted in silico
to encode cell envelope components or proteins usually involved
in bacterial adaptation to changes in environmental conditions, such
as low pH or high osmolarity. This suggets a strong relationship between
the H-NS regulon and the maintenance of intracellular homeostasis
