Changes in the physical state of DNA during replication in regenerating liver of the rat.
Evidence is presented which demonstrates that DNA synthesis in regenerating liver is discontinuous. In pulse-labeling experiments from 30 seconds to 10 minutes, the earliest detectable intermediate in DNA replication appears to be double-stranded DNA which has a significant degree of single-stranded character probably due to the existence of gaps in the newly synthesized strand. The label begins to move into completely double-stranded DNA 10-30 minutes after the commencement of labeling. The average molecular weight of the single-stranded "unit" of DNA replication is determined to be approximately 7.5 million. Smaller units may be produced but not observed as a result of imperfect synchronization of DNA synthesis.
D000818:Animals; D002247:Carbon Isotopes; D002482:Cellulose; D002499:Centrifugation, Density Gradient; D002501:Centrifugation, Zonal; D002852:Chromatography, Ion Exchange; D004247:DNA / Q000096:biosynthesis* / Q000302:isolation & purification; D004261:DNA Replication; D006498:Hepatectomy; D006882:Hydroxyapatites; D008099:Liver / Q000378:metabolism*; D008115:Liver Regeneration; D008297:Male; D008970:Molecular Weight; D009566:Nitrates; D051381:Rats; D014316:Tritium
D002247:Carbon Isotopes; D006882:Hydroxyapatites; D009566:Nitrates; D014316:Tritium; D002482:Cellulose; D004247:DNA