Franco-Echevarría, ElsaGonzález-Polo, NoeliaZorrilla, SilviaMartínez-Lumbreras, SantiagoSantiveri, Clara MCampos Olivas, RamonSánchez, MarCalvo, OlgaGonzález, BeatrizPérez-Cañadillas, José Manuel2019-02-052019-02-052017-09-29Nucleic Acids Res. 2017 ;45(17):10293-10305.0305-1048http://hdl.handle.net/20.500.12105/7105Transcription termination of non-coding RNAs is regulated in yeast by a complex of three RNA binding proteins: Nrd1, Nab3 and Sen1. Nrd1 is central in this process by interacting with Rbp1 of RNA polymerase II, Trf4 of TRAMP and GUAA/G terminator sequences. We lack structural data for the last of these binding events. We determined the structures of Nrd1 RNA binding domain and its complexes with three GUAA-containing RNAs, characterized RNA binding energetics and tested rationally designed mutants in vivo. The Nrd1 structure shows an RRM domain fused with a second α/β domain that we name split domain (SD), because it is formed by two non-consecutive segments at each side of the RRM. The GUAA interacts with both domains and with a pocket of water molecules, trapped between the two stacking adenines and the SD. Comprehensive binding studies demonstrate for the first time that Nrd1 has a slight preference for GUAA over GUAG and genetic and functional studies suggest that Nrd1 RNA binding domain might play further roles in non-coding RNAs transcription termination.engVoRhttp://creativecommons.org/licenses/by/4.0/Amino Acid SequenceConserved SequenceCrystallography, X-RayModels, MolecularMutationNuclear Magnetic Resonance, BiomolecularPeptide FragmentsProtein BindingProtein ConformationProtein DomainsProtein FoldingRNA, FungalRNA, MessengerRNA-Binding ProteinsRecombinant Fusion ProteinsSaccharomyces cerevisiaeSaccharomyces cerevisiae ProteinsSequence AlignmentSubstrate SpecificityTranscription Termination, GeneticAtribución 4.0 Internacional28973465451710293-1030510.1093/nar/gkx6851362-4962Nucleic acids researchopen access