The Organization of DNA Replication in a Mammalian Cell Line

Abstract

The first evidence that DNA replication proceeds in an organized, nonrandom manner at the level of the chromosome was obtained by Taylor (1960) using autoradiographic techniques to examine labeled metaphase chromosomes. His work, and that of Hsu (1964), demonstrated that DNA replication is initiated at multiple sites along the chromosome and that each chromosome shows a reproducible, characteristic pattern of replication in different stages of S phase. It has also been shown that hetero-chromatin tends to be late replicating (see Lima-de-Faria and Jaworska, 1968). Even better resolution is now possible with the fluoresence labeling technique developed by Latt (1973). Both Latt (1975) and Stubblefield (1975) have suggested that chromosome bands which have been visualized as structural units by classical staining procedures are actually units of replication as observed by fluoresence labeling.

A.S.I. Participant