Abstract
The mode of DNA replication was investigated in vivo with Ehrlich ascites tumor cells. Alkaline and neutral sucrose density gradient centrifugations showed that nascent DNA chains, pulse-labelled with [ 3H]thymidine, were shorter than the bulk of the DNA. These short chains of DNA were gradually converted to longer ones and finally to material similar to the bulk of the DNA. Hydroxyapatite column chromatography showed that the nascent DNA chains were single-stranded but as the pulse time was lengthened, they changed to double-stranded DNA. These findings are similar to those obtained on bacterial systems and on some mammalian cells cultured in vitro.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have