title: Properties of a nuclear polyadenylate-protein complex from mouse ascites cells.
abstract: Ribonucleoprotein (RNP) subcomplexes containing at least 60% of the total nuclear poly(A) were isolated from mouse ascites cells; these 15 S ribonucleoprotein particles were most probably derived from larger hnRNA containing complexes. The buoyant density of the 15 S ribonucleoprotein in formaldehyde-CsCl was significantly less than that of the hnRNA-containing 30 S ribonucleoprotein subcomplex, indicating a higher proportion of protein (approximately 80%) in the 15 S ribonucleoprotein. The proteins partially protected the poly(A) from the action of ribonuclease T2. RNA isolated from purified 15 S ribonucleoprotein was estimated to be 190 to 200 nucleotides in length by gel electrophoresis, whereas the RNA from crude preparations was slightly larger. Base composition analysis of 32P-labeled crude 15 S RNP-RNA showed it to be rich in adenylate (70%) but containing a substantial amount of uridylate (20%). The base composition of RNA from purified complexes was approximately 90% adenyalte. Our results suggested that oligo(U) sequences from hnRNA could artificially associated with the poly(A) during preparation of 15 S RNP-RNA.
mesh_terms: D000818:Animals; D001202:Ascitic Fluid / Q000166:cytology; D002467:Cell Nucleus / Q000378:metabolism*; D002499:Centrifugation, Density Gradient; D046911:Macromolecular Substances; D051379:Mice; D008970:Molecular Weight; D009698:Nucleoproteins / Q000378:metabolism; D009843:Oligoribonucleotides / Q000032:analysis; D011061:Poly A / Q000378:metabolism; D011072:Poly U / Q000032:analysis; D011485:Protein Binding; D012261:Ribonucleoproteins / Q000302:isolation & purification / Q000378:metabolism; D012265:Ribonucleotides / Q000032:analysis
chemical_list: D046911:Macromolecular Substances; D009698:Nucleoproteins; D009843:Oligoribonucleotides; D012261:Ribonucleoproteins; D012265:Ribonucleotides; D011061:Poly A; D011072:Poly U