The basic repeating structural (and functional) unit of chromatin is the nucleosome, which contains eight histone proteins and about 146 base pairs of DNA (Van Holde, 1988; Wolffe, 1999).

Chromatin is a flexibly joined chain of nucleosomes that exists inside the nucleus of eukaryotic cells and has been described as a 'bead on a string'. Chromatin organization strengthens DNA for ...