Reconstitution of chromatin: assembly of the nucleosome.

AUTOR(ES)

Wilhelm, F X

RESUMO

The order of reassociation of the four histones H2a, H2b, H3 and H4 to the DNA during the reconstitution of chromatin was determined. At each step of the reconstitution the DNA and associated histones were separated from the free histones by centrifugation in a glycerol gradient. The unbound and reassociated histones were analysed by gel electrophoresis and the histone-DNA complexes characterized by circular dichroism and electron microscopy. We show that H3 and H4 bind first to the DNA between 1.2 M NaCl and 0.85 M NaCl and impose a nucleosome like structure; in a second step histones H2a and H2b are placed around this kernel to complete the nucleosome.

Documentos Relacionados

• The structure of DNA in a nucleosome.
• The helical periodicity of DNA on the nucleosome.
• Primary organization of nucleosome core particle of chromatin: sequence of histone arrangement along DNA.
• Histone contributions to the structure of DNA in the nucleosome.
• Assembly of transfected DNA into chromatin: structural changes in the origin-promoter-enhancer region upon replication.