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Nucleosome

Definition(s)

The repeating structural units of chromatin, each consisting of approximately 200 base pairs of DNA wound around a protein core. This core is composed of the histones H2A, H2B, H3, and H4.

Definition from: MeSH via Unified Medical Language SystemThis link leads to a site outside Genetics Home Reference. at the National Library of Medicine

Any of the repeating globular subunits of chromatin that consist of a complex of DNA and histone and are thought to be present only during interphase.

Definition from: Merriam-Webster's Medical DictionaryThis link leads to a site outside Genetics Home Reference. by Merriam-Webster Inc.

A nucleosome is the basic repeating unit of eukaryotic chromatin. In a human cell, about six feet of DNA must be packaged into a nucleus with a diameter less than a human hair. A single nucleosome consists of about 150 base pairs of DNA sequence wrapped around a core of histone proteins. The nucleosomes are arranged like beads on a string. They are repeatedly folded in on themselves to form a chromosome.

Definition from: Talking Glossary of Genetic TermsThis link leads to a site outside Genetics Home Reference. from the National Human Genome Research Institute

See also Understanding Medical Terminology.

 
Published: July 7, 2014