title: U4 and U6 RNAs coexist in a single small nuclear ribonucleoprotein particle.
abstract: U4 and U6 RNAs of mammalian cells possess extensive intermolecular sequence complementarity and hence have the potential to base pair. A U4/U6 RNA complex, detectable in nondenaturing polyacrylamide gels, is released when human small nuclear ribonucleoproteins (snRNPs) containing U1, U2, U4, U5, and U6 RNAs are dissociated with proteinase K in the presence of sodium dodecyl sulfate. The released RNA/RNA complex dissociates with increasing temperature, consistent with the existence of specific base-pairing between the two RNAs. Since U6 RNA is selectively released from intact snRNPs under the same conditions required to dissociate the U4/U6 RNA complex, the RNA-RNA interaction may be sufficient to maintain U4 and U6 RNAs in the same snRNP particle. The biological implications of these findings are discussed.
mesh_terms: D001482:Base Composition; D001483:Base Sequence; D004591:Electrophoresis, Polyacrylamide Gel; D006367:HeLa Cells / Q000032:analysis; D006801:Humans; D008180:Lupus Erythematosus, Systemic / Q000097:blood; D009690:Nucleic Acid Conformation; D012313:RNA / Q000032:analysis*; D012342:RNA, Small Nuclear; D012261:Ribonucleoproteins / Q000097:blood / Q000302:isolation & purification*; D017411:Ribonucleoproteins, Small Nuclear
chemical_list: D012342:RNA, Small Nuclear; D012261:Ribonucleoproteins; D017411:Ribonucleoproteins, Small Nuclear; D012313:RNA