Nucleoid remodeling during environmental adaptation is regulated by HU-dependent DNA bundling.

ABSTRACT: Bacterial nucleoid remodeling dependent on conserved histone-like protein, HU is one of the determining factors in global gene regulation. By imaging of near-native, unlabeled E. coli cells by soft X-ray tomography, we show that HU remodels nucleoids by promoting the formation of a dense condensed core surrounded by less condensed isolated domains. Nucleoid remodeling during cell growth and environmental adaptation correlate with pH and ionic strength controlled molecular switch that regulated HUαα dependent intermolecular DNA bundling. Through crystallographic and solution-based studies we show that these effects mechanistically rely on HUαα promiscuity in forming multiple electrostatically driven multimerization interfaces. Changes in DNA bundling consequently affects gene expression glo

SUBMITTER: Remesh SG 

PROVIDER: S-EPMC7283360 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature