Folding of the DNA double helix in chromatin-like structures from simian virus 40.
نویسندگان
چکیده
Relaxed circular, covalently closed simian virus 40 DNA molecules were associated with the four histones that are present in virions. In electron micrographs the resulting complexes appear twisted, with globular structures (nucleosomes) along the DNA. Incubation with an untwisting extract converts the twisted complexes to relaxed structures. Extraction of the DNA from the relaxed complexes yields supercoiled molecules. The number of superhelical turns in these molecules corresponds to the number of nucleosomes per DNA molecule in the complexes.
منابع مشابه
Influence of nucleosome structure on the three-dimensional folding of idealized minichromosomes.
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عنوان ژورنال:
- Proceedings of the National Academy of Sciences of the United States of America
دوره 72 5 شماره
صفحات -
تاریخ انتشار 1975