title: Abscisic Acid Induces Resistance againstBamboo Mosaic VirusthroughArgonaute2and3.
abstract: Plant resistance to pathogens is tuned by defense-related hormones. Of these, abscisic acid (ABA) is well documented to moderate resistance against fungi and bacteria. However, ABA's contribution to resistance against viruses is pleiotropic. ABA affects callose deposition at plasmodesmata (therefore hindering the viral cell-to-cell movement), but here, we show that when callose synthase is down-regulated, ABA still induces resistance against infection withBamboo mosaic virus(BaMV). By examining the potential connections between the ABA and RNA-silencing pathways in Arabidopsis (Arabidopsis thaliana), we showed that ABA regulates the expression of almost the whole ARGONAUTE (AGO) gene family, of which some are required for plant resistance against BaMV Our data show that BaMV infection and ABA treatment regulate the same set of AGOs, with positive effects onAGO1,AGO2, andAGO3, no effect onAGO7, and negative effects onAGO4andAGO10The BaMV-mediated regulation ofAGO1,AGO2, andAGO3is ABA dependent, because the accumulation of theseAGOsin BaMV-infected ABA mutants did not reach the levels observed in infected wild-type plants. In addition, theAGO1-miR168acomplex is dispensable for BaMV resistance, whileAGO2andAGO3were important for ABA-mediated resistance. While mostagomutants showed increased susceptibility to BaMV infection (exceptago10),ago1-27showed reduced BaMV titers, which was attributed to the up-regulated levels ofAGO2,AGO3, andAGO4We have established that ABA regulates the expression of several members of the AGO family, and this regulation partially contributes to ABA-mediated resistance against BaMV These findings reveal another role for ABA in plants.
authors.affiliation: Institute of Plant and Microbial Biology, Academia Sinica, Nankang, Taipei 11529, Taiwan, Republic of China (M.A., M.-H.H., N.-S.L.); and.|Département de Biologie, Université de Sherbrooke, Sherbrooke, Quebec, Canada J1K 2R1 (P.M.).
authors.forename: Mazen
authors.identifier: http://orcid.org/0000-0003-3690-7459
authors.initials: M
authors.lastname: Alazem
authors.affiliation: Institute of Plant and Microbial Biology, Academia Sinica, Nankang, Taipei 11529, Taiwan, Republic of China (M.A., M.-H.H., N.-S.L.); and.|Département de Biologie, Université de Sherbrooke, Sherbrooke, Quebec, Canada J1K 2R1 (P.M.).
authors.forename: Meng-Hsun
authors.identifier: http://orcid.org/0000-0001-8026-1400
authors.initials: MH
authors.lastname: He
authors.affiliation: Institute of Plant and Microbial Biology, Academia Sinica, Nankang, Taipei 11529, Taiwan, Republic of China (M.A., M.-H.H., N.-S.L.); and.|Département de Biologie, Université de Sherbrooke, Sherbrooke, Quebec, Canada J1K 2R1 (P.M.).
authors.forename: Peter
authors.initials: P
authors.lastname: Moffett
authors.affiliation: Institute of Plant and Microbial Biology, Academia Sinica, Nankang, Taipei 11529, Taiwan, Republic of China (M.A., M.-H.H., N.-S.L.); and nslin@sinica.edu.tw.|Département de Biologie, Université de Sherbrooke, Sherbrooke, Quebec, Canada J1K 2R1 (P.M.) nslin@sinica.edu.tw.
authors.forename: Na-Sheng
authors.identifier: http://orcid.org/0000-0003-1148-6256
authors.initials: NS
authors.lastname: Lin
mesh_terms: D000040:Abscisic Acid / Q000494:pharmacology*; D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism / Q000382:microbiology; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D060565:Argonaute Proteins / Q000235:genetics* / Q000378:metabolism; D060467:Disease Resistance / Q000235:genetics*; D018506:Gene Expression Regulation, Plant / Q000187:drug effects*; D009154:Mutation; D010935:Plant Diseases / Q000235:genetics / Q000821:virology; D010937:Plant Growth Regulators / Q000494:pharmacology; D030821:Plants, Genetically Modified; D017863:Potexvirus / Q000502:physiology
chemical_list: C000626002:AGO3 protein, Arabidopsis; D029681:Arabidopsis Proteins; D060565:Argonaute Proteins; D010937:Plant Growth Regulators; C559855:argonaute 2 protein, Arabidopsis; D000040:Abscisic Acid