title: Arabidopsis clade IV TGA transcription factors, TGA10 and TGA9, are involved in ROS-mediated responses to bacterial PAMP flg22.
abstract: Reactive oxygen species (ROS) produced in chloroplasts have been proposed to act as signaling molecules for plant immunity through pathogen-associated molecular patterns (PAMPs), such as flg22. To elucidate this process, we herein conducted genetic screening of flg22-sensitive mutants from T-DNA insertion lines lacking chloroplastic H2O2-responsive genes. The results obtained showed that knockout mutants lacking a clade IV TGA transcription factor, TGA10, were more sensitive to the flg22 treatment than wild-type plants. Furthermore, although no flg22-sensitive phenotype was detected in the knockout mutant of another clade IV TGA9, double knockout tga9 tga10 mutants showed more sensitivity to flg22 than single knockout mutants. Transcripts of TGA10 and TGA9 were strongly induced by flg22 in leaves, and this was facilitated by the double knockout of stromal and thylakoid-bound ascorbate peroxidases (APX), which are major H2O2scavengers in chloroplasts. The flg22-induced H2O2accumulation was maintained at high level in these APXs mutants, indicating the clade IV TGAs may be induced by the ROS. Furthermore, TGA10 was required for the complete activation of the expression of several flg22-responsive genes in plants treated with this PAMP. These have provided a new insight into the relationship between the TGA transcription factors and ROS-mediated signaling in PAMPs responses.
authors.affiliation: Department of Advanced Bioscience, Faculty of Agriculture, Kinki University, Nakamachi, Nara 631-8505, Japan. Electronic address: nb_noshi@nara.kindai.ac.jp.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Noshi
authors.affiliation: Department of Advanced Bioscience, Faculty of Agriculture, Kinki University, Nakamachi, Nara 631-8505, Japan. Electronic address: 1533690009t@nara.kindai.ac.jp.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Mori
authors.affiliation: Department of Advanced Bioscience, Faculty of Agriculture, Kinki University, Nakamachi, Nara 631-8505, Japan. Electronic address: nb_noritanabe@nara.kindai.ac.jp.
authors.forename: Noriaki
authors.initials: N
authors.lastname: Tanabe
authors.affiliation: Department of Life Science and Biotechnology, Faculty of Life and Environmental Science, Shimane University, 1060 Nishikawatsu, Matsue, Shimane 690-8504, Japan. Electronic address: maruta@life.shimane-u.ac.jp.
authors.forename: Takanori
authors.initials: T
authors.lastname: Maruta
authors.affiliation: Department of Advanced Bioscience, Faculty of Agriculture, Kinki University, Nakamachi, Nara 631-8505, Japan. Electronic address: shigeoka@nara.kindai.ac.jp.
authors.forename: Shigeru
authors.initials: S
authors.lastname: Shigeoka
mesh_terms: D017360:Arabidopsis / Q000276:immunology* / Q000382:microbiology / Q000502:physiology; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D050976:Basic-Leucine Zipper Transcription Factors / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D055786:Gene Knockout Techniques; D016254:Mutagenesis, Insertional; D000069452:Pathogen-Associated Molecular Pattern Molecules / Q000276:immunology*; D057865:Plant Immunity; D012333:RNA, Messenger / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism*; D015398:Signal Transduction; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism / Q000502:physiology*
chemical_list: D029681:Arabidopsis Proteins; D050976:Basic-Leucine Zipper Transcription Factors; D000069452:Pathogen-Associated Molecular Pattern Molecules; D012333:RNA, Messenger; D017382:Reactive Oxygen Species; C000617111:TGA10 protein, Arabidopsis; C000617112:TGA9 protein, Arabidopsis; D014157:Transcription Factors
keywords: Arabidopsis thaliana; Reactive oxygen species; TGA factor; flg22