Replication of DNA by nuclei isolated from soybean suspension cultures.

DNA replication was studied in nuclei isolated from soybean cells grown in suspension culture. The isolation procedure involved the preparation of protoplasts, their lysis with a nonionic detergent and purification of nuclei. These nuclei synthesized low molecular weight DNA and joined these fragments into DNA of intermediate molecular weight. The characteristics of replication in isolated nuclei correlated well with those of the cells from which they were isolated, as shown by fluorodeoxyuridine synchronization and ultraviolet irradiation experiments.