title: Interaction of mammalian splicing factor SF3a with U2 snRNP and relation of its 60-kD subunit to yeast PRP9.
abstract: In the assembly of a prespliceosome, U2 small nuclear ribonucleoprotein (snRNP) functions in pre-messenger RNA (mRNA) splicing together with splicing factors (SFs) 3a, SF3b, and several other proteins. The 17S but not the 12S form of U2 snRNP is active in splicing-complex formation. Here it is shown that the SF3a subunits correspond to three of the 17S U2 snRNP-specific polypeptides. SF3a interacts with U2 snRNP in the presence of SF3b to generate a structure similar to 17S U2 snRNP, which suggests a function for SF3a and SF3b in the incorporation of U2 snRNP into the spliceosome. Furthermore, the 60-kilodalton subunit of SF3a is related to the yeast splicing protein PRP9.
authors.affiliation: Département de Biologie Cellulaire, Sciences III, Université de Genève, Switzerland.
authors.forename: R
authors.initials: R
authors.lastname: Brosi
authors.forename: K
authors.initials: K
authors.lastname: Gröning
authors.forename: S E
authors.initials: SE
authors.lastname: Behrens
authors.forename: R
authors.initials: R
authors.lastname: Lührmann
authors.forename: A
authors.initials: A
authors.lastname: Krämer
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D003429:Cross Reactions; D004591:Electrophoresis, Polyacrylamide Gel; D005656:Fungal Proteins / Q000737:chemistry / Q000276:immunology / Q000378:metabolism*; D006801:Humans; D009687:Nuclear Proteins / Q000737:chemistry / Q000276:immunology / Q000378:metabolism*; D012326:RNA Splicing; D000072260:RNA Splicing Factors; D016601:RNA-Binding Proteins; D017413:Ribonucleoprotein, U2 Small Nuclear / Q000737:chemistry / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins; D017381:Spliceosomes / Q000378:metabolism*
chemical_list: D005656:Fungal Proteins; D009687:Nuclear Proteins; C065574:PRP9 protein, S cerevisiae; D000072260:RNA Splicing Factors; D016601:RNA-Binding Proteins; D017413:Ribonucleoprotein, U2 Small Nuclear; D029701:Saccharomyces cerevisiae Proteins; D000255:Adenosine Triphosphate