DNA Methylation and Gene Activity: The Adenovirus System as a Model

For reasons perhaps more profound than mere analogy, DNA can be compared with language (Doerfler 1982a). Like language, DNA stores and conveys information, and it can be mutated and modified; the principles of information storage and transfer are universal (Comrie 1981). This paper deals with a highly specific modification of DNA, i.e., DNA methylation. The biochemistry of DNA methylation has been extensively studied (for review of older literature, see Meselson et al. 1972; Arber 1974), but only recently have functional aspects of this modification been recognized (for review, see Razin and Riggs 1980; Doerfler 1981, 1983; Ehrlich and Wang 1981; Hattman 1981; Razin and Friedman 1981; Wigler 1981).