title: Identification of RNA targets for the nuclear multidomain cyclophilin atCyp59 and their effect on PPIase activity.
abstract: AtCyp59 is a multidomain cyclophilin containing a peptidyl-prolyl cis/trans isomerase (PPIase) domain and an evolutionarily highly conserved RRM domain. Deregulation of this class of cyclophilins has been shown to affect transcription and to influence phosphorylation of the C-terminal repeat domain of the largest subunit of the RNA polymerase II. We used a genomic SELEX method for identifying RNA targets of AtCyp59. Analysis of the selected RNAs revealed an RNA-binding motif (G[U/C]N[G/A]CC[A/G]) and we show that it is evolutionarily conserved. Binding to this motif was verified by gel shift assays in vitro and by RNA immunopreciptation assays of AtCyp59 in vivo. Most importantly, we show that binding also occurs on unprocessed transcripts in vivo and that binding of specific RNAs inhibits the PPIase activity of AtCyp59 in vitro. Surprisingly, genome-wide analysis showed that the RNA motif is present in about 70% of the annotated transcripts preferentially in exons. Taken together, the available data suggest that these cyclophilins might have an important function in transcription regulation.
authors.affiliation: Max F. Perutz Laboratories, Medical University of Vienna, Vienna, Austria.
authors.forename: Olga
authors.initials: O
authors.lastname: Bannikova
authors.forename: Marek
authors.initials: M
authors.lastname: Zywicki
authors.forename: Yamile
authors.initials: Y
authors.lastname: Marquez
authors.forename: Tatsiana
authors.initials: T
authors.lastname: Skrahina
authors.forename: Maria
authors.initials: M
authors.lastname: Kalyna
authors.forename: Andrea
authors.initials: A
authors.lastname: Barta
mesh_terms: D029681:Arabidopsis Proteins / Q000378:metabolism*; D021983:Cyclophilins / Q000378:metabolism*; D023281:Genomics / Q000379:methods; D059372:Nucleotide Motifs; D012319:RNA Polymerase II / Q000378:metabolism; D012333:RNA, Messenger / Q000737:chemistry* / Q000378:metabolism*; D018749:RNA, Plant / Q000737:chemistry / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; D012333:RNA, Messenger; D018749:RNA, Plant; D016601:RNA-Binding Proteins; D012319:RNA Polymerase II; D021983:Cyclophilins; C510650:cyclophilin 59, Arabidopsis