title: Reconstituted U1 small nuclear ribonucleoprotein complex restores 5' splice site cleavage activity.
abstract: Functional reconstitution of U1 small nuclear ribonucleoprotein particle (U1 snRNP) was performed using in vitro transcribed U1 snRNA. Hela cell nuclear extract was depleted of its constituent snRNPs by centrifugation at 100,000 X g. The supernatant was devoid of snRNAs and lacked cleavage activity in splicing reactions using in vitro transcribed beta-globin pre-mRNA as substrate. The resulting pellet which contained the snRNAs, retained 5' splice site cleavage activity in a similar splicing reaction. Supplementation of the inactive supernatant fraction with in vitro transcribed U1 snRNA, partially restored 5' splice site cleavage activity thereby demonstrating the specific requirement of U1 snRNP in the initial stage of pre-mRNA splicing.
authors.affiliation: George Washington University, Department of Genetics, Washington D.C. 20037.
authors.forename: C B
authors.initials: CB
authors.lastname: Siegall
authors.forename: T T
authors.initials: TT
authors.lastname: Hla
authors.forename: A
authors.initials: A
authors.lastname: Kumar
mesh_terms: D002467:Cell Nucleus / Q000378:metabolism; D003001:Cloning, Molecular; D005796:Genes; D005914:Globins / Q000235:genetics*; D006367:HeLa Cells / Q000378:metabolism; D006801:Humans; D012322:RNA Precursors / Q000235:genetics; D012326:RNA Splicing; D012342:RNA, Small Nuclear / Q000235:genetics; D012261:Ribonucleoproteins / Q000235:genetics*; D017411:Ribonucleoproteins, Small Nuclear; D013698:Templates, Genetic; D014158:Transcription, Genetic
chemical_list: D012322:RNA Precursors; D012342:RNA, Small Nuclear; D012261:Ribonucleoproteins; D017411:Ribonucleoproteins, Small Nuclear; D005914:Globins