Fig. 2

Chinese hamster Y RNAs can substitute for hY RNAs for the reconstitution of chromosomal DNA replication. Quantitative analysis of replicating G1-phase nuclei in vitro (see “Methods”). Human EJ30 nuclei were separately incubated with buffer, unfractionated cytosol of HeLa cells (S100), fractions QA and ArFT, and with fractions supplemented with 300 ng of the individual RNAs synthesized in vitro as indicated [8]. The human 5S ribosomal RNA was used as negative control. Mean values and standard deviations of the proportions of replicating nuclei from 3 to 4 independent experiments (n) are shown. *P < 0.05 (student’s t test) when compared to negative control reaction containing 5S rRNA