5S RNA III, a new nucleus-specific 5S RNA

Abstract

A new species of 5S RNA, referred to as 5S RNA III, has been found in the Novikoff hepatoma ascites cell nuclei. This RNA, which composes 28% of total nuclear 5S RNA and co-migrates with ribosomal 5S RNA I and 5S RNA II on 8% polyacrylamide gel electrophoresis, has been isolated by chromatography on DEAE Sephadex columns. The nucleotide composition is A 24, U 31, G 24 and C 20; its A+U G+C ratio is 1.24. T 1 RNase digestion produced the following unique olig o nucleotides from 5S RNA III: (U 2C 2)Gp, (CUA)Gp, (C 4A 3U 8)Gp, [(UmU) (C 2A 3U 5) (AGmC)], (CAU 2)Gp, (C 2AU 2)Gp and (C 3A 3U 2)Gp. Similarly, unique oligonucleotides were produced by complete pancreatic RNase digestion of 5S RNA III, including UmUp, A-A-Up, A-A-Cp, (AG)Cp, A-Gm-Cp, (A 2G)Up, A-A-A-Up and (A 3G)-Up.