Properties and Kinetics of Development of Rous Sarcoma Virus-Infected Cells Evidenced by Methylene Blue Staining

Publisher Website
Google Scholar
Abstract
Three different kinds of areas of infected cells corresponding to different focus formation stages can be evidenced by methylene blue (MB) staining in cultures of chick embryo (CE) fibroblasts infected at low multiplicity with the temperature-sensitive (ts) mutant of Rous sarcoma virus (RSV), FU19, which transforms these fibroblasts at 37° but not at 41°. These are: (a) areas of MB-stainable cells with transformed phenotype (STP areas = foci); (b) areas of MB-stainable cells with normal phenotype (SNP areas), and (c) areas of MB-unstainable cells with normal phenotype (USNP areas). DNA and RNA synthesis and virus production were followed in these various stages at 37° and at 41°. The results show that when cultures are shifted from 37° to 41°, virus production in the SNP and USNP areas which arise by phenotypic reversion of STP foci remains comparable to that of the latter foci. On the contrary, DNA and RNA synthesis are markedly reduced in SNP and USNP areas, DNA synthesis falling down to the level of uninfected cells, and RNA synthesis remaining somewhat higher. The kinetics of development of SNP and STP areas in cultures infected with FU19 and with the parental virus SR4 were also compared. The results confirm that SNP areas are precursors of STP areas but that this passage occurs at a slower rate in cultures infected with FU19.

This publication has 0 references indexed in Scilit: