Alpha-radiation-induced amplification of integrated SV40 sequences is mediated by a trans-acting mechanism.
Treatment of Chinese hamster embryo cells with alpha irradiation (4 MeV, emitted by 241americium) induces a 15-fold amplification of integrated SV40 sequences. The extent of amplification depends on the dose of irradiation and on the presence of a functional T-antigen encoded by the SV40 A gene. The inducing signal can be transmitted to a non-irradiated nucleus following cell fusion. Amplification is therefore the result of some trans-acting process, and this could explain how SV40 amplification can occur after doses of alpha irradiation that are too low to cause direct DNA damage within the SV40 replicon.
D000512:Alpha Particles; D000818:Animals; D001483:Base Sequence; D002459:Cell Fusion; D002478:Cells, Cultured; D006224:Cricetinae; D004279:DNA, Viral / Q000032:analysis*; D005784:Gene Amplification / Q000528:radiation effects*; D011336:Probability; D013539:Simian virus 40 / Q000235:genetics* / Q000528:radiation effects
D004279:DNA, Viral