title: ARGONAUTE PIWI domain and microRNA duplex structure regulate small RNA sorting in Arabidopsis.
abstract: Small RNAs (sRNAs) are loaded into ARGONAUTE (AGO) proteins to induce gene silencing. In plants, the 5'-terminal nucleotide is important for sRNA sorting into different AGOs. Here we show that microRNA (miRNA) duplex structure also contributes to miRNA sorting. Base pairing at the 15th nucleotide of a miRNA duplex is important for miRNA sorting in both Arabidopsis AGO1 and AGO2. AGO2 favours miRNA duplexes with no middle mismatches, whereas AGO1 tolerates, or prefers, duplexes with central mismatches. AGO structure modelling and mutational analyses reveal that the QF-V motif within the conserved PIWI domain contributes to recognition of base pairing at the 15th nucleotide of a duplex, while the DDDE catalytic core of AtAGO2 is important for recognition of the central nucleotides. Finally, we rescued the adaxialized phenotype of ago1-12, which is largely due to miR165 loss-of-function, by changing miR165 duplex structure which we predict redirects it to AGO2.
authors.affiliation: 1] Department of Plant Pathology and Microbiology, Center for Plant Cell Biology and Institute for Integrative Genome Biology, University of California, Riverside, California 92521, USA [2] State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China.
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Zhang
authors.affiliation: 1] Department of Plant Pathology and Microbiology, Center for Plant Cell Biology and Institute for Integrative Genome Biology, University of California, Riverside, California 92521, USA [2] Department of Plant Protection, Nanjing Agriculture University, Nanjing 210095, China.
authors.forename: DongDong
authors.initials: D
authors.lastname: Niu
authors.affiliation: Donald Danforth Plant Science Center, St Louis, Missouri 63132, USA.
authors.forename: Alberto
authors.initials: A
authors.lastname: Carbonell
authors.affiliation: 1] Department of Plant Pathology and Microbiology, Center for Plant Cell Biology and Institute for Integrative Genome Biology, University of California, Riverside, California 92521, USA [2] Key Laboratory of Bio-pesticide and Chemistry Biology, Ministry of Education, Fujian Agricultural and Forestry University, Fuzhou 350002, China.
authors.forename: Airong
authors.initials: A
authors.lastname: Wang
authors.affiliation: Department of Plant Pathology and Microbiology, Center for Plant Cell Biology and Institute for Integrative Genome Biology, University of California, Riverside, California 92521, USA.
authors.forename: Angel
authors.initials: A
authors.lastname: Lee
authors.affiliation: Department of Plant Pathology and Microbiology, Center for Plant Cell Biology and Institute for Integrative Genome Biology, University of California, Riverside, California 92521, USA.
authors.forename: Vinnary
authors.initials: V
authors.lastname: Tun
authors.affiliation: Key Laboratory of Bio-pesticide and Chemistry Biology, Ministry of Education, Fujian Agricultural and Forestry University, Fuzhou 350002, China.
authors.forename: Zonghua
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Donald Danforth Plant Science Center, St Louis, Missouri 63132, USA.
authors.forename: James C
authors.initials: JC
authors.lastname: Carrington
authors.affiliation: Department of Chemistry, University of California Riverside, Riverside, California 92521, USA.
authors.forename: Chia-en A
authors.initials: CE
authors.lastname: Chang
authors.affiliation: Department of Plant Pathology and Microbiology, Center for Plant Cell Biology and Institute for Integrative Genome Biology, University of California, Riverside, California 92521, USA.
authors.forename: Hailing
authors.initials: H
authors.lastname: Jin
mesh_terms: D017360:Arabidopsis; D029681:Arabidopsis Proteins / Q000378:metabolism*; D060565:Argonaute Proteins / Q000378:metabolism*; D035683:MicroRNAs / Q000378:metabolism*; D011485:Protein Binding; D054730:Protein Interaction Domains and Motifs; D034443:RNA Transport
chemical_list: C117457:AGO1 protein, Arabidopsis; D029681:Arabidopsis Proteins; D060565:Argonaute Proteins; D035683:MicroRNAs; C559855:argonaute 2 protein, Arabidopsis