Lytic infection by double-strand DNA viruses and cell cycle alterations

Polyomaviruses, papillomaviruses, adenoviruses and herpesviruses are double -stranded DNA viruses that replicate in the nucleus of the cells they infec t and have evolved various strategies to create a cellular environment that is optimally conducive to their replication. One of these strategies consi sts of activating cellular genes, mostly S-phase genes that are required fo r the replication of the viral genome. Concomitantly, they encode one or se veral proteins that negatively regulate the response of the cell to viral i nfection, notably cell cycle arrest and/or apoptosis. As a result, these vi ruses profoundly alter the biochemical pathways that normally control cellu lar growth, and may thus promote uncontrolled cell proliferation. This revi ew describes some well-known mechanisms of cell cycle alteration induced by these viruses. (C) 2000 Editions scientifiques et medicales Elsevier SAS.