In organisms whose cells have a nucleus, like plants and animals, the basic packaging units of DNA are the so-called nucleosomes. A nucleosome consists of a segment of DNA wound around eight proteins known as histones. Gene expression, which lies at the basis of protein production, requires "reading" DNA, for which DNA needs to be temporarily unwrapped. Detailed studies, and especially visualizations, of DNA–histone and nucleosome dynamics are crucial for a better understanding of DNA unwrapping and related processes.
