Direct and reverse transport of RNA in a system of isolated HeLa cell nuclei

In a system containing isolated HeLa cell nuclei the release of RNA from the nuclei may be paralleled with the antagonistic process, i. e., RNA translocation into the nuclei. The RNA release from the nuclei depends on incubation time, pH, Mg2+ and nucleoside triphosphate concentration. The rate of reverse transport depends on pH, size of RNA to be translocated and the physiological state of the nuclear membrane. Low molecular weight RNAs (less than 10 S) are translocated into the nuclei most effectively. The nuclei of synchronized HeLa cells in the G1-period are more "permeable" for translocated RNA as compared with the S-phase HeLa cell nuclei.