title: Structural analysis of human 2'-O-ribose methyltransferases involved in mRNA cap structure formation.
abstract: The 5' cap of human messenger RNA contains 2'-O-methylation of the first and often second transcribed nucleotide that is important for its processing, translation and stability. Human enzymes that methylate these nucleotides, termed CMTr1 and CMTr2, respectively, have recently been identified. However, the structures of these enzymes and their mechanisms of action remain unknown. In the present study, we solve the crystal structures of the active CMTr1 catalytic domain in complex with a methyl group donor and a capped oligoribonucleotide, thereby revealing the mechanism of specific recognition of capped RNA. This mechanism differs significantly from viral enzymes, thus providing a framework for their specific targeting. Based on the crystal structure of CMTr1, a comparative model of the CMTr2 catalytic domain is generated. This model, together with mutational analysis, leads to the identification of residues involved in RNA and methyl group donor binding.
authors.affiliation: 1] Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, ul. ks. Trojdena 4, PL-02-109 Warsaw, Poland [2] Laboratory of Protein Structure, International Institute of Molecular and Cell Biology in Warsaw, ul. ks. Trojdena 4, PL-02-109 Warsaw, Poland.
authors.forename: Miroslaw
authors.initials: M
authors.lastname: Smietanski
authors.affiliation: Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, ul. ks. Trojdena 4, PL-02-109 Warsaw, Poland.
authors.forename: Maria
authors.initials: M
authors.lastname: Werner
authors.affiliation: Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, ul. ks. Trojdena 4, PL-02-109 Warsaw, Poland.
authors.forename: Elzbieta
authors.initials: E
authors.lastname: Purta
authors.affiliation: Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, ul. ks. Trojdena 4, PL-02-109 Warsaw, Poland.
authors.forename: Katarzyna H
authors.initials: KH
authors.lastname: Kaminska
authors.affiliation: Division of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, ul. Zwirki i Wigury 93, PL-02-089 Warsaw, Poland.
authors.forename: Janusz
authors.initials: J
authors.lastname: Stepinski
authors.affiliation: 1] Division of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, ul. Zwirki i Wigury 93, PL-02-089 Warsaw, Poland [2] Centre of New Technologies, University of Warsaw, ul. Zwirki i Wigury 93, PL-02-089 Warsaw, Poland.
authors.forename: Edward
authors.initials: E
authors.lastname: Darzynkiewicz
authors.affiliation: Laboratory of Protein Structure, International Institute of Molecular and Cell Biology in Warsaw, ul. ks. Trojdena 4, PL-02-109 Warsaw, Poland.
authors.forename: Marcin
authors.initials: M
authors.lastname: Nowotny
authors.affiliation: 1] Laboratory of Bioinformatics and Protein Engineering, International Institute of Molecular and Cell Biology in Warsaw, ul. ks. Trojdena 4, PL-02-109 Warsaw, Poland [2] Laboratory of Bioinformatics, Institute of Molecular Biology and Biotechnology, Faculty of Biology, Adam Mickiewicz University, ul. Umultowska 89, PL-61-614 Poznan, Poland.
authors.forename: Janusz M
authors.initials: JM
authors.lastname: Bujnicki
mesh_terms: D018360:Crystallography, X-Ray; D006801:Humans; D008780:Methyltransferases / Q000378:metabolism*; D008958:Models, Molecular; D017434:Protein Structure, Tertiary; D012315:RNA Caps / Q000378:metabolism*; D012323:RNA Processing, Post-Transcriptional; D012333:RNA, Messenger / Q000378:metabolism*
chemical_list: D012315:RNA Caps; D012333:RNA, Messenger; C530219:CMTR1 protein, human; C560501:CMTR2 protein, human; D008780:Methyltransferases