Chromatography of nuclear 4–7-S RNA on DEAE-Sephadex columns

Abstract

Chromatography on DEAE-Sephadex columns is a useful method for large-scale purification of components of nuclear 4–7-S RNA inasmuch as 30 mg of RNA were satisfactorily fractionated by this method. Nuclear 4–7-S RNA was separated into several distinct peaks by elution with a 0.5–0.8 M NaCl gradient at pH 3.4, 5.1 or 7.6. Of the various components, 4-S, 5-S and U2 RNA were highly purified by chromatography at pH 7.6 as shown by analytical polyacrylamide gel electrophoresis. At pH 5.1 or 3.4, U1 RNA was isolated in a highly purified state in a yield of 7% of total 4–7-S RNA. The 4.5-S nuclear RNA which was obtained as an electrophoretically homogeneous fraction by disc gel electrophoresis was fractionated into at least two components by chromatography on DEAE-Sephadex columns. In addition, the 5-S nuclear RNA was separated into three components.