Processing of RNA by cytoplasmic extract. Synthesis and processing of RNA by isolated HeLa cell nuclei incubated with cytoplasmic extract.

Nuclei are isolated from HeLa cells by a low speed centrifugation procedure. These nuclei can carry out RNA synthesis at 30 degrees. The effect of cytoplasmic extract on the transport and processing of RNA is measured. In the presence of cytoplasmic extract the precursor to 4S RNA is processed to 4S RNA and an RNA species OF 7-9S is transported outside the nuclei.