Linker histones incorporation maintains chromatin fiber plasticity.
Biophys J
; 100(11): 2726-35, 2011 Jun 08.
Article
in En
| MEDLINE
| ID: mdl-21641318
ABSTRACT
Genomic DNA in eukaryotic cells is organized in supercoiled chromatin fibers, which undergo dynamic changes during such DNA metabolic processes as transcription or replication. Indeed, DNA-translocating enzymes like polymerases produce physical constraints in vivo. We used single-molecule micromanipulation by magnetic tweezers to study the response of chromatin to mechanical constraints in the same range as those encountered in vivo. We had previously shown that under positive torsional constraints, nucleosomes can undergo a reversible chiral transition toward a state of positive topology. We demonstrate here that chromatin fibers comprising linker histones present a torsional plasticity similar to that of naked nucleosome arrays. Chromatosomes can undergo a reversible chiral transition toward a state of positive torsion (reverse chromatosome) without loss of linker histones.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Chromatin
/
Histones
/
Mechanical Phenomena
Language:
En
Journal:
Biophys J
Year:
2011
Document type:
Article
Affiliation country:
France