Dominance of the CPE(+) phenotype in hybrid Aedes albopictus cells infected with Sindbis virus.

The effect of Sindbis virus (SV) infection was analyzed in hybrid Aedes albopictus cells formed by fusing ouabain-resistant CPE(+) cells to CPE(-) alpha-amanitin resistant cells. Although the 24-h yields of virus from the parental CPE(+) and CPE(-) clones were similar, the rates of viral RNA synthesis and virus release at early times post-infection were higher in the CPE(+) cells. In all eight hybrid clones studied, the CPE(+) phenotype was dominant. In addition, the kinetics of viral RNA synthesis and virus release in the hybrids closely resembled what was observed in the CPE(+) parent clone. These data indicate that both in the parental and in the hybrid cells, expression of SV-induced CPE is associated with a high level of viral RNA synthesis and a rapid production of virus during the early period after infection. It is suggested that CPE(+) cells contain some factor or activity which is lacking or less abundant in the CPE(-) cells and that this activity is important in the regulation of viral RNA synthesis.