Abstract
In bacteria, the contribution of global nucleoid organization in determining cellular transcription programs is unclear. Using a mutant form of the most abundant nucleoid-associated protein HU, HUalpha(E38K,V42L), we previously showed that nucleoid remodeling by the mutant protein re-organizes the global transcription pattern. Here, we demonstrate that, unlike the dimeric wild-type HU, HUalpha(E38K,V42L) is an octamer and wraps DNA around its surface. The formation of wrapped nucleoprotein complexes by HUalpha(E38K,V42L) leads to a high degree of DNA condensation. The DNA wrapping is right-handed, which restrains positive supercoils. In vivo, HUalpha(E38K,V42L) shows altered association and distribution patterns with the genetic loci whose transcription are differentially affected in the mutant strain.
Publication types
-
Comparative Study
-
Research Support, Non-U.S. Gov't
MeSH terms
-
Carrier Proteins / chemistry*
-
Carrier Proteins / genetics
-
Carrier Proteins / ultrastructure
-
Chromatin / chemistry
-
Chromatin / genetics
-
DNA, Superhelical / chemistry*
-
DNA, Superhelical / ultrastructure
-
DNA-Binding Proteins / chemistry*
-
DNA-Binding Proteins / genetics
-
DNA-Binding Proteins / ultrastructure
-
Dimerization
-
Escherichia coli Proteins / chemistry*
-
Escherichia coli Proteins / genetics
-
Escherichia coli Proteins / ultrastructure
-
Genetic Markers
-
Glutamic Acid / genetics
-
Histones / chemistry*
-
Histones / genetics
-
Leucine / genetics
-
Lysine / genetics
-
Microscopy, Atomic Force
-
Mutation
-
Protein Isoforms / chemistry
-
Protein Isoforms / genetics
-
Protein Isoforms / ultrastructure
-
Transcription Factors / chemistry*
-
Transcription Factors / genetics
-
Transcription Factors / ultrastructure
-
Valine / genetics
Substances
-
Carrier Proteins
-
Chromatin
-
DNA, Superhelical
-
DNA-Binding Proteins
-
Escherichia coli Proteins
-
Genetic Markers
-
Histones
-
Protein Isoforms
-
Transcription Factors
-
hns protein, E coli
-
hupA protein, E coli
-
Glutamic Acid
-
Leucine
-
Valine
-
Lysine