title: TbMP57 is a 3' terminal uridylyl transferase (TUTase) of the Trypanosoma brucei editosome.
abstract: RNA editing produces mature trypanosome mitochondrial mRNAs by uridylate (U) insertion and deletion. In insertion editing, Us are added to the pre-mRNA by a 3' terminal uridylyl transferase (TUTase) activity. We report the identification of a TUTase activity that copurifies with in vitro editing and is catalyzed by the integral editosome protein TbMP57. TbMP57 catalyzes the addition of primarily a single U to single-stranded (ss) RNA and adds the number of Us specified by a guide RNA to insertion editing-like substrates. TbMP57 is distinct from a previously identified TUTase that adds many Us to ssRNA and which we find is neither a stable editosome component nor does it add Us to editing-like substrates. Recombinant TbMP57 specifically interacts with the editosome protein TbMP81, and this interaction enhances the TUTase activity. These results suggest that TbMP57 catalyzes U addition to pre-mRNA during editing.
authors.affiliation: Seattle Biomedical Research Institute, Seattle, WA 98109, USA.
authors.forename: Nancy Lewis
authors.initials: NL
authors.lastname: Ernst
authors.forename: Brian
authors.initials: B
authors.lastname: Panicucci
authors.forename: Robert P
authors.initials: RP
authors.lastname: Igo
authors.forename: Aswini K
authors.initials: AK
authors.lastname: Panigrahi
authors.forename: Reza
authors.initials: R
authors.lastname: Salavati
authors.forename: Kenneth
authors.initials: K
authors.lastname: Stuart
mesh_terms: D000818:Animals; D002384:Catalysis; D002847:Chromatography, Agarose; D002850:Chromatography, Gel; D002852:Chromatography, Ion Exchange; D008928:Mitochondria / Q000737:chemistry / Q000201:enzymology*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D017434:Protein Structure, Tertiary; D015800:Protozoan Proteins; D012313:RNA / Q000235:genetics / Q000378:metabolism; D017393:RNA Editing; D012322:RNA Precursors / Q000235:genetics / Q000378:metabolism; D017394:RNA, Guide, Kinetoplastida / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000378:metabolism; D012261:Ribonucleoproteins / Q000378:metabolism; D013379:Substrate Specificity; D014346:Trypanosoma brucei brucei / Q000166:cytology / Q000201:enzymology* / Q000235:genetics; D006599:UDPglucose-Hexose-1-Phosphate Uridylyltransferase / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism*
chemical_list: D015800:Protozoan Proteins; D012322:RNA Precursors; D012333:RNA, Messenger; D011994:Recombinant Proteins; D012261:Ribonucleoproteins; C437997:TbMP81 protein, Trypanosoma brucei; D012313:RNA; D006599:UDPglucose-Hexose-1-Phosphate Uridylyltransferase; D017394:RNA, Guide, Kinetoplastida