title: Mungbean yellow mosaic Indian virus encoded AC2 protein suppresses RNA silencing by inhibiting Arabidopsis RDR6 and AGO1 activities.
abstract: RNA silencing refers to a conserved RNA-directed gene regulatory mechanism in a wide range of eukaryotes. It plays an important role in many processes including growth, development, genome stability, and antiviral defense in the plants. Geminivirus encoded AC2 is identified as an RNA silencing suppressor protein, however, the mechanism of action has not been characterized. In this paper, we elucidate another mechanism of AC2-mediated suppression activity of Mungbean Yellow Mosaic India Virus (MYMIV). The AC2 protein, unlike many other suppressors, does not bind to siRNA or dsRNA species and its suppression activity is mediated through interaction with key components of the RNA silencing pathway, viz., RDR6 and AGO1. AC2 interaction inhibits the RDR6 activity, an essential component of siRNA and tasi-RNA biogenesis and AGO1, the major slicing factor of RISC. Thus the study identifies dual sites of MYMIV-AC2 interference and probably accounts for its strong RNA silencing suppression activity.
authors.affiliation: Plant Molecular Biology, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi 110067, India; Department of Physiology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee 53226, USA. Electronic address: vikashkumarhi@yahoo.com.
authors.forename: Vikash
authors.initials: V
authors.lastname: Kumar
authors.affiliation: Plant Molecular Biology, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi 110067, India.
authors.forename: Sumona Karjee
authors.initials: SK
authors.lastname: Mishra
authors.affiliation: Plant Molecular Biology, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi 110067, India; Department of Genetics & Plant Breeding, Sher-e-Bangla Agricultural University, Dhaka 1207, Bangladesh.
authors.forename: Jamilur
authors.initials: J
authors.lastname: Rahman
authors.affiliation: Plant Molecular Biology, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi 110067, India; Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720, USA.
authors.forename: Jyoti
authors.initials: J
authors.lastname: Taneja
authors.affiliation: Plant Molecular Biology, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi 110067, India.
authors.forename: Geethaa
authors.initials: G
authors.lastname: Sundaresan
authors.affiliation: Plant Molecular Biology, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi 110067, India.
authors.forename: Neeti Sanan
authors.initials: NS
authors.lastname: Mishra
authors.affiliation: Plant Molecular Biology, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi 110067, India; Department of Genetics, University of Delhi, South Campus, Benito Juarez Marg, New Delhi 110021, India. Electronic address: sunilmukherjee@hotmail.com.
authors.forename: Sunil K
authors.initials: SK
authors.lastname: Mukherjee
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism / Q000821:virology*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D060565:Argonaute Proteins / Q000235:genetics / Q000378:metabolism*; D053839:Begomovirus / Q000235:genetics / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D015536:Down-Regulation; D020868:Gene Silencing; D054884:Host-Pathogen Interactions; D010935:Plant Diseases / Q000235:genetics / Q000821:virology*; D012324:RNA-Dependent RNA Polymerase / Q000235:genetics / Q000378:metabolism*; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: C099182:AC2 protein, geminivirus; C117457:AGO1 protein, Arabidopsis; D029681:Arabidopsis Proteins; D060565:Argonaute Proteins; D004268:DNA-Binding Proteins; D014764:Viral Proteins; C514575:RDR6 protein, Arabidopsis; D012324:RNA-Dependent RNA Polymerase
keywords: AC2; AGO1; Geminivirus; PTGS; RDR6; TasiRNA