title: The carbon/nitrogen regulator ARABIDOPSIS TOXICOS EN LEVADURA31 controls papilla formation in response to powdery mildew fungi penetration by interacting with SYNTAXIN OF PLANTS121 in Arabidopsis.
abstract: The carbon/nitrogen (C/N) balance of plants is not only required for growth and development but also plays an important role in basal immunity. However, the mechanisms that link C/N regulation and basal immunity are poorly understood. We previously demonstrated that the Arabidopsis (Arabidopsis thaliana) Arabidopsis Tóxicos en Levadura31 (ATL31) ubiquitin ligase, a regulator of the C/N response, positively regulates the defense response against bacterial pathogens. In this study, we identified the plasma membrane-localized soluble N-ethylmaleimide-sensitive fusion protein attachment protein receptor SYNTAXIN OF PLANTS121 (SYP121) as a novel ATL31 interactor. The syp121-1 loss-of-function mutant showed similar hypersensitivity to C/N stress conditions as the atl31 atl6 double mutant. SYP121 is essential for resistance to penetration by powdery mildew fungus and positively regulates the formation of cell wall appositions (papillae) at fungal entry sites. Microscopic analysis demonstrated that ATL31 was specifically localized around papillae. In addition, ATL31 overexpressors showed accelerated papilla formation, enhancing their resistance to penetration by powdery mildew fungus. Together, these data indicate that ATL31 plays an important role in connecting the C/N response with basal immunity by promoting papilla formation through its association with SYP121.
authors.affiliation: Faculty of Science and Graduate School of Life Science, Hokkaido University, Sapporo 060-0810, Japan.
authors.forename: Shugo
authors.initials: S
authors.lastname: Maekawa
authors.forename: Noriko
authors.initials: N
authors.lastname: Inada
authors.forename: Shigetaka
authors.initials: S
authors.lastname: Yasuda
authors.forename: Yoichiro
authors.initials: Y
authors.lastname: Fukao
authors.forename: Masayuki
authors.initials: M
authors.lastname: Fujiwara
authors.forename: Takeo
authors.initials: T
authors.lastname: Sato
authors.forename: Junji
authors.initials: J
authors.lastname: Yamaguchi
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000276:immunology* / Q000382:microbiology* / Q000502:physiology; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D001203:Ascomycota / Q000502:physiology*; D002244:Carbon / Q000378:metabolism; D002473:Cell Wall / Q000382:microbiology*; D060467:Disease Resistance / Q000276:immunology; D005453:Fluorescence; D018506:Gene Expression Regulation, Plant; D018525:Germination / Q000235:genetics; D047468:Immunoprecipitation; D009584:Nitrogen / Q000378:metabolism; D010935:Plant Diseases / Q000276:immunology* / Q000382:microbiology; D011485:Protein Binding; D050765:Qa-SNARE Proteins / Q000235:genetics / Q000378:metabolism*; D013312:Stress, Physiological; D044767:Ubiquitin-Protein Ligases / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; C479425:PEN1 protein, Arabidopsis; D050765:Qa-SNARE Proteins; D002244:Carbon; C547213:ATL31 protein, Arabidopsis; D044767:Ubiquitin-Protein Ligases; D009584:Nitrogen