title: Overexpression of oligouridylate binding protein 1b results in ABA hypersensitivity.
abstract: Oligouridylate binding protein 1b (UBP1b), a marker protein of plant stress granules (SGs), plays a role in heat stress tolerance in plants. A previous microarray analysis revealed that the expression of several ABA signaling-related genes is higher in UBP1b-overexpressing Arabidopsis plants (UBP1b-ox) subjected to both non-stressed and heat stress conditions. Root elongation and seed germination assays demonstrated that UBP1b-ox exhibited hypersensitivity to ABA. RT-qPCR analysis confirmed that mitogen-activated protein kinase (MAPK) cascade genes, such as MPK3, MKK4, and MKK9 were upregulated in UBP1b-ox plants. ABA receptor genes, including PYL5 and PYL6, were also upregulated in UBP1b-ox plants. mRNA of WRKY33 - a downstream gene of MPK3 and an upstream gene of ethylene biosynthesis, exhibited high levels of accumulation, although the level of endogenous ABA was not significantly different between UBP1b-ox and control plants. In addition, RNA decay analysis revealed that WRKY33 was more stable in UBP1b-ox plants, indicating that the mRNA of WRKY33 was protected within UBP1b SGs. Collectively, these data demonstrate that UBP1b plays an important role in plant response to ABA.
authors.affiliation: a Plant Genomic Network Research Team , RIKEN Center for Sustainable Resource Science (CSRS) , Yokohama , Kanagawa , Japan.|b Kihara Institute for Biological Research, Yokohama City University , Yokohama , Kanagawa , Japan.
authors.forename: Cam Chau
authors.initials: CC
authors.lastname: Nguyen
authors.affiliation: a Plant Genomic Network Research Team , RIKEN Center for Sustainable Resource Science (CSRS) , Yokohama , Kanagawa , Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Nakaminami
authors.affiliation: a Plant Genomic Network Research Team , RIKEN Center for Sustainable Resource Science (CSRS) , Yokohama , Kanagawa , Japan.
authors.forename: Akihiro
authors.initials: A
authors.lastname: Matsui
authors.affiliation: c Dormancy and Adaptation Research Unit , RIKEN Center for Sustainable Resource Science (CSRS) , Yokohama , Kanagawa , Japan.
authors.forename: Shunsuke
authors.initials: S
authors.lastname: Watanabe
authors.affiliation: c Dormancy and Adaptation Research Unit , RIKEN Center for Sustainable Resource Science (CSRS) , Yokohama , Kanagawa , Japan.
authors.forename: Yuri
authors.initials: Y
authors.lastname: Kanno
authors.affiliation: c Dormancy and Adaptation Research Unit , RIKEN Center for Sustainable Resource Science (CSRS) , Yokohama , Kanagawa , Japan.
authors.forename: Mitsunori
authors.initials: M
authors.lastname: Seo
authors.affiliation: a Plant Genomic Network Research Team , RIKEN Center for Sustainable Resource Science (CSRS) , Yokohama , Kanagawa , Japan.|b Kihara Institute for Biological Research, Yokohama City University , Yokohama , Kanagawa , Japan.|d CREST, JST, Honcho , Kawaguchi , Saitama , Japan.
authors.forename: Motoaki
authors.initials: M
authors.lastname: Seki
mesh_terms: D000040:Abscisic Acid / Q000494:pharmacology; D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant / Q000187:drug effects / Q000235:genetics; D030821:Plants, Genetically Modified / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D020871:RNA Stability / Q000187:drug effects / Q000235:genetics
chemical_list: D029681:Arabidopsis Proteins; D000040:Abscisic Acid
keywords: ABA response; ABA sensitivity; RNA stability; UBP1b; UBP1b stress granule