Title: Histones
Literature References: Small chromosomal proteins (mol wt 12,000-20,000) possessing an open, unfolded structure, attached to DNA of cell nuclei by ionic linkages. First isolated from bird erythrocytes: Kossel, Z. Physiol. Chem. 8, 511 (1884). Prepd also from cell nuclei of calf thymus, spleen, and liver, liver and spleen of leukemic rats, bovine spermatozoa: Hnilica, Biochem. J. 82, 123 (1962); Berry, Mayer, Exp. Cell Res. 20, 116 (1960). Classification is based on relative amounts of lysine and arginine: Histone I is very rich in lysine and has several subtypes; histone II, moderately rich in lysine with two subtypes; histone III, moderately rich in arginine, contains cysteine; histone IV, very rich in arginine and in glycine. Histones of the same type obtained from various plant and animal sources are very similar in amino acid sequence. Amino acid composition of animal histones: Hnilica et al., Biochim. Biophys. Acta 124, 109 (1966); of plant histones and similarity of plant and animal histones: Fambrough, Bonner, Biochemistry 5, 2563 (1966). Complete amino acid sequence of calf thymus histone IV: DeLange et al., J. Biol. Chem. 244, 319 (1969); Ogawa et al., ibid. 4387; of histone III: DeLange et al., Proc. Natl. Acad. Sci. USA 69, 882 (1972); eidem, J. Biol. Chem. 248, 3261 (1973); Hooper et al., ibid. 3275; of the two subtypes of histone II: Iwai et al., Nature 226, 1056 (1970); Yeoman et al., J. Biol. Chem. 247, 6018 (1972). Toxicity study: Starbuck et al., Arch. Int. Pharmacodyn. Ther. 165, 374 (1967). Review of structural studies: DeLange, Acc. Chem. Res. 5, 368 (1972). Review of histone in the chromosome structure: Bradbury et al., Ann. N.Y. Acad. Sci. 222, 266 (1973). Review of biological functions: Binner, Garrard, Life Sci. 14, 209 (1974). General review: Butler et al., Prog. Biophys. Mol. Biol. 18, 211 (1968); R. J. DeLange, E. L. Smith in Proteins vol. 4, H. Neurath, R. L. Hill, Eds. (Academic, New York, 3rd ed., 1979) pp 134-243.
Properties: Histones are susceptible to enzymatic cleavage; sol in an Hg2SO4-H2SO4 medium. Infrared spectra: de Lozé, Compt. Rend. 246, 417 (1958). LD50 i.v. in rats of lysine-rich, slightly lysine-rich, and arginine-rich histones: 90, 60-70, 60 mg/kg (Starbuck).
Toxicity data: LD50 i.v. in rats of lysine-rich, slightly lysine-rich, and arginine-rich histones: 90, 60-70, 60 mg/kg (Starbuck) |