Figure 1.

Multiple levels of chromatin assembly. (A) The overlong DNA is highly compacted through association with core histones to form nucleosomes, and then chromatosomes by histone H1 binding. Several aspects show a great impact on chromatin dynamics (interconversion of euchromatin and heterochromatin), such as modifications of DNA, modifications of histones, and other protein complexes that interact with chromatin. (B) Structural domains of the linker histone H1. Although the globular domain (GH1) is the only folded portion of the protein in solution, all three domains are subjected to multiple posttranslational modifications (PTMs). (NTD) amino-terminal domain, (CTD) carboxy-terminal domain.