Herpesviridae

The definitions used in this glossary of terminology either have been provided by the authors of the articles, or have been extracted wholly or in part, or paraphrased from the following sources: The American Medical Association Encyclopedia of Medicine, Charles B. Clayman, MD, Medical Editor, Random House, New York, 1989; Biotechnology from A to Z, 2d Edition, William Bains, Oxford University Press, New York, New York, 2002; A Dictionary of Genetics, 6th Edition, Robert C. King and William D. Stansfield, Oxford University Press, New York, New York, 2002; Dorland's Illustrated Medical Dictionary, 29th and 30th Editions, W. B. Saunders Company, Philadelphia, 2000, 2003; Genes VII, Benjamin Lewin, Oxford University Press, New York, New York, 2000; The Gale Encyclopedia of Genetic Disorders, Volumes I and II, Stacey L. Blachford, Ed., Thomson Learning, New York, New York, 2002; The Merriam-Webster Dictionary, Merriam-Webster, Inc., Springfield, Massachusetts, 1997; Molecular Biology of the Cell, 3rd Edition, Bruce Alberts, et al., Garland Publishing, 1994; The Random House Dictionary of the English Language, Unabridged Edition, 1966; Webster's Ninth New Collegiate Dictionary, 1991.

DEFINITION:

Herpesviridae
The herpesviruses: a family of DNA viruses having a virion 150-200 nm in diameter consisting of four components: a lipid bilayer envelope with surface projections, a tegument of amorphous material, an icosahedral nucleocapsid with 162 prismatic capsomers, and a protein spool on which the DNA is wrapped. The genome consists of a single molecule of linear double-stranded DNA (MW 70-150 x 106, size 120-200 kbp). Viruses contain at least 30 structural polypeptides and are sensitive to lipid solvents, heat, and extremes of pH. Replication occurs in the nucleus and the envelope is acquired by budding through the inner lamella of the nuclear membrane; virions are released by transport via the endoplasmic reticulum to the cell membrane. Persistence for the lifetime of the host is common and some herpesviruses induce neoplasia. There are three subfamilies: Alphaherpesvirinae, Betaherpesvirinae, and Gammaherpesvirinae. A large number of herpesviruses have not yet been assigned to a subfamily or genus.