A theoretical model of a chromatin fiber is shown. This length of 30 nm fiber would package about 20,000 base pairs of DNA. It is made from 100 nucleosomes (PDB entry 1eqz) with centers arranged helically and orientations somewhat randomized. The white tablets show the arrangements of the nucleosomes in a more schematic way. The bottom images show a ribbon diagram of a single nucleosome face on and edge on.
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