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n. Any of several small, basic proteins most commonly found in association with the DNA in the chromatin of eukaryotes.

n. Any of various simple water soluble proteins that are rich in the basic amino acids lysine and arginine and are complexed with DNA in the nucleosomes of eukaryotic chromatin.

n. a simple protein containing mainly basic amino acids; present in cell nuclei in association with nucleic acids

"There is a sophisticated code, known as the histone code, that directs the decisions as to which parts of the DNA sequence are transcribed into mRNA and which are not."

simple protein   

alpha-glucosidase    trypsin    metalloproteinase    proteasome    reuptake    microtubule    thrombin    cyclooxygenase    primary-response    caspase