title: Identification of an evolutionarily divergent U11 small nuclear ribonucleoprotein particle in Drosophila.
abstract: Previous reports suggested that U11, in contrast to U12 or other small nuclear (sn)RNAs of the U12-type spliceosome, might be either highly divergent or absent in Drosophila melanogaster. Affinity purification of Drosophila U12-containing complexes has led to the identification of the fly U11 snRNA, which contains a potential U12-type 5' splice-site-interacting sequence, but whose sequence and length differs significantly from vertebrate and plant U11. Analysis of U12-type introns revealed an A-rich region directly downstream of Drosophila, but not human, U12-type 5' splice sites. This finding, coupled with the presence of a highly divergent U11 snRNA, and the apparent absence of Drosophila homologs of human U11 proteins, suggest that U12-type 5' splice site recognition might be different in flies. A comparison of U11 snRNAs that we have identified from vertebrates, plants, and insects, suggests that an evolutionarily divergent U11 snRNA may be unique to Drosophila and not characteristic of insects in general.
authors.affiliation: Department of Cellular Biochemistry, Max Planck Institute of Biophysical Chemistry, 37077 Goettingen, Germany.
authors.forename: Claudia
authors.initials: C
authors.lastname: Schneider
authors.forename: Cindy L
authors.initials: CL
authors.lastname: Will
authors.forename: Jürgen
authors.initials: J
authors.lastname: Brosius
authors.forename: Mikko J
authors.initials: MJ
authors.lastname: Frilander
authors.forename: Reinhard
authors.initials: R
authors.lastname: Lührmann
mesh_terms: D000818:Animals; D017360:Arabidopsis / Q000737:chemistry / Q000235:genetics; D001483:Base Sequence; D029721:Drosophila Proteins / Q000737:chemistry* / Q000235:genetics*; D004331:Drosophila melanogaster / Q000737:chemistry* / Q000235:genetics*; D019143:Evolution, Molecular; D006801:Humans; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D022821:RNA Splice Sites / Q000235:genetics; D018749:RNA, Plant / Q000737:chemistry / Q000235:genetics; D012342:RNA, Small Nuclear / Q000737:chemistry / Q000235:genetics; D017411:Ribonucleoproteins, Small Nuclear / Q000737:chemistry* / Q000235:genetics*
chemical_list: D029721:Drosophila Proteins; D022821:RNA Splice Sites; D018749:RNA, Plant; D012342:RNA, Small Nuclear; D017411:Ribonucleoproteins, Small Nuclear; C488423:U11 small nuclear ribonucleoprotein, Drosophila; C552126:U11-U12 small nuclear ribonucleoprotein; C096986:U12 small nuclear RNA