title: Mutational analysis of structural elements in a class-I cyclic di-GMP riboswitch to elucidate its regulatory mechanism.
abstract: The Vc2 riboswitch possesses an aptamer domain belonging to the class-I c-di-GMP riboswitch family. This domain has been analysed and the molecular mechanism by which it recognizes the c-di-GMP ligand has been elucidated. On the other hand, the regulatory mechanism of the full-length Vc2 riboswitch to control its downstream open reading frame (ORF) remains largely unknown. In this study, we performed in vivo reporter assays and in vitro biochemical analyses of the full-length riboswitch and its aptamer domain. We evaluated the results of in vivo and in vitro analyses to elucidate the regulatory mechanism of the Vc2 riboswitch. The present results suggest that recognition of c-di-GMP ligand by the Vc2 riboswitch aptamer domain downregulates expression of its downstream ORF primarily at the translational level.
authors.affiliation: Department of Chemistry, Graduate School of Science and Engineering, University of Toyama, Toyama 930-8555, Japan.
authors.forename: Saki
authors.initials: S
authors.lastname: Inuzuka
authors.affiliation: Department of Chemistry and Biochemistry, Graduate School of Engineering, Kyushu University, Fukuoka 819-0395, Japan.
authors.forename: Kei-Ichiro
authors.initials: K
authors.lastname: Nishimura
authors.affiliation: Department of Chemistry, Graduate School of Science and Engineering, University of Toyama, Toyama 930-8555, Japan.
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Kakizawa
authors.affiliation: Department of Chemistry and Biochemistry, Graduate School of Engineering, Kyushu University, Fukuoka 819-0395, Japan.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Fujita
authors.affiliation: Department of Chemistry and Biochemistry, Graduate School of Engineering, Kyushu University, Fukuoka 819-0395, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Furuta
authors.affiliation: Department of Chemistry, Graduate School of Science and Engineering, University of Toyama, Toyama 930-8555, Japan.
authors.forename: Shigeyoshi
authors.initials: S
authors.lastname: Matsumura
authors.affiliation: Department of Chemistry, Graduate School of Science and Engineering, University of Toyama, Toyama 930-8555, Japan yikawa@sci.u-toyama.ac.jp.
authors.forename: Yoshiya
authors.initials: Y
authors.lastname: Ikawa
mesh_terms: D006152:Cyclic GMP / Q000031:analogs & derivatives* / Q000737:chemistry / Q000378:metabolism; D009690:Nucleic Acid Conformation; D016366:Open Reading Frames / Q000502:physiology*; D058928:Riboswitch / Q000502:physiology*
chemical_list: D058928:Riboswitch; C062025:bis(3',5')-cyclic diguanylic acid; D006152:Cyclic GMP
keywords: RNA structure; bacterial RNA; c-di-GMP; non-coding RNA; riboswitch