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histone
histone , any of a class of protein molecules found in the chromosomes of eukaryotic cells . They complex with the DNA (see nucleic acid ) and pack the DNA into tight masses of chromatin, which have the structure of coiled coils, much like a tangled telephone cord. The molecules are strongly basic and of relatively small size. They also serve a function in the transcription of DNA. The histones are rich in the amino acids arginine and lysine ; the five major subtypes of the class differ from one another chiefly in the relative amounts of these two amino acids. They have been greatly conserved during evolution, histone structures vary little in a wide range of organisms. |
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"histone." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. 29 May. 2012 <http://www.encyclopedia.com>. "histone." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. (May 29, 2012). http://www.encyclopedia.com/doc/1E1-histone.html "histone." The Columbia Encyclopedia, 6th ed.. 2011. Retrieved May 29, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-histone.html |
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histone
histone Any of a group of water-soluble proteins found in association with the DNA of plant and animal chromosomes. They contain a large proportion of the basic (positively charged) amino acids lysine, arginine, and histidine. They are involved in the condensation and coiling of chromosomes during cell division and have also been implicated in nonspecific suppression of gene activity (see chromatin). Histones do not occur in vertebrate sperm cells (see protamine) or in bacteria, although a very similar protein has been found in the genome of the archaebacterium Thermoplasma.
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"histone." A Dictionary of Biology. 2004. Encyclopedia.com. 29 May. 2012 <http://www.encyclopedia.com>. "histone." A Dictionary of Biology. 2004. Encyclopedia.com. (May 29, 2012). http://www.encyclopedia.com/doc/1O6-histone.html "histone." A Dictionary of Biology. 2004. Retrieved May 29, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O6-histone.html |
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histone
histone One of a group of basic, globular, simple proteins that have a high content of the amino acids arginine and lysine. Histones form part of the chromosomal material of eukaryotic cells and appear to play an important, but as yet incompletely understood, role in gene regulation.
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MICHAEL ALLABY. "histone." A Dictionary of Plant Sciences. 1998. Encyclopedia.com. 29 May. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "histone." A Dictionary of Plant Sciences. 1998. Encyclopedia.com. (May 29, 2012). http://www.encyclopedia.com/doc/1O7-histone.html MICHAEL ALLABY. "histone." A Dictionary of Plant Sciences. 1998. Retrieved May 29, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O7-histone.html |
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histone
histone One of a group of basic, globular, simple proteins that have a high content of the amino acids arginine and lysine. Histones form part of the chromosomal material of eukaryotic cells and appear to play an important, but as yet incompletely understood, role in gene regulation.
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Cite this article
MICHAEL ALLABY. "histone." A Dictionary of Zoology. 1999. Encyclopedia.com. 29 May. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "histone." A Dictionary of Zoology. 1999. Encyclopedia.com. (May 29, 2012). http://www.encyclopedia.com/doc/1O8-histone.html MICHAEL ALLABY. "histone." A Dictionary of Zoology. 1999. Retrieved May 29, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O8-histone.html |
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histones
histones Proteins rich in arginine and lysine, soluble in water but not dilute ammonia. They occur mainly in the cell nucleus and are concerned with the regulation of DNA.
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DAVID A. BENDER. "histones." A Dictionary of Food and Nutrition. 2005. Encyclopedia.com. 29 May. 2012 <http://www.encyclopedia.com>. DAVID A. BENDER. "histones." A Dictionary of Food and Nutrition. 2005. Encyclopedia.com. (May 29, 2012). http://www.encyclopedia.com/doc/1O39-histones.html DAVID A. BENDER. "histones." A Dictionary of Food and Nutrition. 2005. Retrieved May 29, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O39-histones.html |
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histone
histone (hist-ohn) n. a simple protein that combines with a nucleic acid to form a nucleoprotein.
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"histone." A Dictionary of Nursing. 2008. Encyclopedia.com. 29 May. 2012 <http://www.encyclopedia.com>. "histone." A Dictionary of Nursing. 2008. Encyclopedia.com. (May 29, 2012). http://www.encyclopedia.com/doc/1O62-histone.html "histone." A Dictionary of Nursing. 2008. Retrieved May 29, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O62-histone.html |
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