Probing the (H3-H4)2 histone tetramer structure using pulsed EPR spectroscopy combined with site-directed spin labelling.

ABSTRACT: The (H3-H4)(2) histone tetramer forms the central core of nucleosomes and, as such, plays a prominent role in assembly, disassembly and positioning of nucleosomes. Despite its fundamental role in chromatin, the tetramer has received little structural investigation. Here, through the use of pulsed electron-electron double resonance spectroscopy coupled with site-directed spin labelling, we survey the structure of the tetramer in solution. We find that tetramer is structurally more heterogeneous on its own than when sequestered in the octamer or nucleosome. In particular, while the central region including the H3-H3' interface retains a structure similar to that observed in nucleosomes, other regions such as the H3 alphaN helix display increased structural heterogeneity. Flexibility of the H

SUBMITTER: Bowman A 

PROVIDER: S-EPMC2810997 | biostudies-literature | 2010 Jan

REPOSITORIES: biostudies-literature