Nucleoid remodeling by an altered HU protein: reorganization of the transcription program.
Bacterial nucleoid organization is believed to have minimal influence on the global transcription program. Using an altered bacterial histone-like protein, HUalpha, we show that reorganization of the nucleoid configuration can dynamically modulate the cellular transcription pattern. The mutant protein transformed the loosely packed nucleoid into a densely condensed structure. The nucleoid compaction, coupled with increased global DNA supercoiling, generated radical changes in the morphology, physiology, and metabolism of wild-type K-12 Escherichia coli. Many constitutive housekeeping genes involved in nutrient utilization were repressed, whereas many quiescent genes associated with virulence were activated in the mutant. We propose that, as in eukaryotes, the nucleoid architecture dictates the global transcription profile and, consequently, the behavior pattern in bacteria.
Kar
Sudeshna
S
Laboratory of Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892-4264, USA.
Edgar
Rotem
R
Adhya
Sankar
S
D001426:Bacterial Proteins / Q000502:physiology*; D005075:Biological Evolution; D002876:Chromosomes, Bacterial; D004278:DNA, Superhelical; D004268:DNA-Binding Proteins / Q000502:physiology*; D013696:Temperature; D014158:Transcription, Genetic; D014774:Virulence
D001426:Bacterial Proteins; D004278:DNA, Superhelical; D004268:DNA-Binding Proteins; C040330:histone-like protein HU, bacteria