Decrease of DNA synthesis in amniotic fluid cells during the middle part of S-phase revealed by differential chromosome staining after incorporation of BrdU
✍ Scribed by W. Schempp; W. Vogel
- Publisher
- Springer
- Year
- 1978
- Tongue
- English
- Weight
- 826 KB
- Volume
- 67
- Category
- Article
- ISSN
- 0009-5915
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✦ Synopsis
The time sequence of DNA replication in partially synchronized human amniotic fluid cells has been analysed, employing BrdU incorporation techniques.--Regardless of the interval between removal of the methotrexate/uridine block and addition of BrdU during S-phase, the treatment results in an R-type replication pattern. Conversely, replacement of BrdU containing medium by another one with thymidine yields G-type replication patterns. A thymidine pulse during the first 4 h of S-phase results in R-type replication patterns; from 7--10 h after block removal it produces G-type pattern. In between, only faint red staining dots can be found indicating a marked decrease of replicational activity during the middle part of the S-phase.