title: Synaptotagmin 1 Negatively Controls the Two Distinct Immune Secretory Pathways to Powdery Mildew Fungi in Arabidopsis.
abstract: PEN1, one of the plasma membrane (PM) syntaxins, comprises an immune exocytic pathway by forming the soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) complex with SNAP33 and VAMP721/722 in plants. Although this secretory pathway is also involved in plant growth and development, how plants control their exocytic activity is as yet poorly understood. Since constitutive PEN1 cycling between the PM and endocytosed vesicles is critical for its immune activity, we studied here the relationship of PEN1 to synaptotagmin 1 (SYT1) that is known to regulate endocytosis at the PM. Interestingly, syt1 plants showed enhanced disease resistance to the Arabidopsis-adapted Golovinomyces orontii fungus, and elevated protein but not transcript levels of PEN1 Calcium-dependent promotion of PEN1-SYT1 interaction suggests that SYT1 controls defense activities of the PEN1-associated secretory pathway by post-translationally modulating PEN1. Increased PEN1-SYT1 interaction and inhibited PEN1 SNARE complex induction by G. orontii additionally suggest that the adaption of phytopathogens to host plants might partly result from effective suppression of the PEN1-related secretory pathway. Further genetic analyses revealed that SYT1 also regulates the atypical peroxisomal myrosinase PEN2-associated secretory pathway.
authors.affiliation: Max-Planck-Institut für Züchtungsforschung, Department of Plant Microbe Interactions, Carl-von-Linné-Weg 10, D-50829 Köln, Germany Center for Genome Engineering, Institute for Basic Science, Daejeon 305-811, Korea These authors contributed equally to this work. ranny@ibs.re.kr hsyun@konkuk.ac.kr chiank@dankook.ac.kr.
authors.forename: Hyeran
authors.initials: H
authors.lastname: Kim
authors.affiliation: Department of Molecular Biology, Dankook University, Yongin 448-701, Korea These authors contributed equally to this work.
authors.forename: Hyeokjin
authors.initials: H
authors.lastname: Kwon
authors.affiliation: Department of Molecular Biology, Dankook University, Yongin 448-701, Korea.
authors.forename: Soohong
authors.initials: S
authors.lastname: Kim
authors.affiliation: Department of Molecular Biology, Dankook University, Yongin 448-701, Korea.
authors.forename: Mi Kyung
authors.initials: MK
authors.lastname: Kim
authors.affiliation: Departamento de Biologia Molecular y Bioquimica, Universidad de Malaga, 29071 Malaga, Spain.
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Botella
authors.affiliation: Department of Biological Sciences, Konkuk University, Seoul 143-701, Korea ranny@ibs.re.kr hsyun@konkuk.ac.kr chiank@dankook.ac.kr.
authors.forename: Hye Sup
authors.initials: HS
authors.lastname: Yun
authors.affiliation: Department of Molecular Biology, Dankook University, Yongin 448-701, Korea ranny@ibs.re.kr hsyun@konkuk.ac.kr chiank@dankook.ac.kr.
authors.forename: Chian
authors.initials: C
authors.lastname: Kwon
mesh_terms: D017360:Arabidopsis / Q000276:immunology* / Q000382:microbiology*; D029681:Arabidopsis Proteins / Q000378:metabolism*; D001203:Ascomycota / Q000502:physiology*; D060467:Disease Resistance / Q000276:immunology; D010935:Plant Diseases / Q000276:immunology* / Q000382:microbiology*; D011485:Protein Binding; D050600:SNARE Proteins / Q000378:metabolism; D055571:Secretory Pathway / Q000276:immunology*; D050863:Synaptotagmin I / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; D050600:SNARE Proteins; D050863:Synaptotagmin I; C000606467:At2g20990 protein, Arabidopsis
keywords: PEN1; PEN2; Plant immunity; SYT1; Secretory pathway