Chromatin core particle unfolding induced by tryptic cleavage of histones.

AUTOR(ES)

Lilley, D M

RESUMO

Chromatin 'core particles' have been digested with trypsin to varying extents. The resulting particles are homogeneous by the criterion of ultracentrifuge boundary analysis. Sedimentation coefficients are lowered as cleavages are introduced into the histones, showing that an unfolding of the core particle occurs. This unfolding is further characterised by a lower melting temperature together with a premelting phase, higher molar ellipticity in the circular dichroism spectra at 280 nm and increased kinetics of digestion by both micrococcal nuclease and DNase I. Differences are also observed in the products of nuclease digestion. The most consistent interpretation of the data involves an unfolding process whereby free rods of DNA are released to extend from a nucleoprotein core.

Documentos Relacionados

• Conformation of DNA in chromatin reconstituted from poly [d(A-T)] and the core histones.
• Remodeling the chromatin structure of a nucleosome array by transcription factor-targeted trans-displacement of histones.
• Erythroid-specific gene chromatin has an altered association with linker histones.
• A positive role for nucleosome mobility in the transcriptional activity of chromatin templates: restriction by linker histones.
• Histone hyperacetylation can induce unfolding of the nucleosome core particle.