title: Changes in PUB22 Ubiquitination Modes Triggered by MITOGEN-ACTIVATED PROTEIN KINASE3 Dampen the Immune Response.
abstract: Crosstalk between posttranslational modifications, such as ubiquitination and phosphorylation, play key roles in controlling the duration and intensity of signaling events to ensure cellular homeostasis. However, the molecular mechanisms underlying the regulation of negative feedback loops remain poorly understood. Here, we uncover a pathway inArabidopsis thalianaby which a negative feedback loop involving the E3 ubiquitin ligase PUB22 that dampens the immune response is triggered by MITOGEN-ACTIVATED PROTEIN KINASE3 (MPK3), best known for its function in the activation of signaling. PUB22's stability is controlled by MPK3-mediated phosphorylation of residues localized in and adjacent to the E2 docking domain. We show that phosphorylation is critical for stabilization by inhibiting PUB22 oligomerization and, thus, autoubiquitination. The activity switch allows PUB22 to dampen the immune response. This regulatory mechanism also suggests that autoubiquitination, which is inherent to most single unit E3s in vitro, can function as a self-regulatory mechanism in vivo.
authors.affiliation: Independent Junior Research Group-Ubiquitination in Immunity, Leibniz Institute of Plant Biochemistry, Halle (Saale) 06120, Germany.|ScienceCampus Halle-Plant-Based Bioeconomy, D-06120 Halle (Saale), Germany.
authors.forename: Giulia
authors.initials: G
authors.lastname: Furlan
authors.affiliation: RIKEN Center for Sustainable Resource Science, Plant Proteomics Research Unit, Yokohama 230-0045, Japan.|Max-Planck-Institute for Plant Breeding Research, Protein Mass Spectrometry Service, Cologne 50829, Germany.
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Nakagami
authors.affiliation: Department of Stress and Developmental Biology, Leibniz Institute of Plant Biochemistry, Halle (Saale) 06120, Germany.
authors.forename: Lennart
authors.initials: L
authors.lastname: Eschen-Lippold
authors.affiliation: Department of Stress and Developmental Biology, Leibniz Institute of Plant Biochemistry, Halle (Saale) 06120, Germany.
authors.forename: Xiyuan
authors.initials: X
authors.lastname: Jiang
authors.affiliation: Proteome Analytics, Leibniz Institute of Plant Biochemistry, Halle (Saale) 06120, Germany.
authors.forename: Petra
authors.initials: P
authors.lastname: Majovsky
authors.affiliation: Independent Junior Research Group-Ubiquitination in Immunity, Leibniz Institute of Plant Biochemistry, Halle (Saale) 06120, Germany.|ScienceCampus Halle-Plant-Based Bioeconomy, D-06120 Halle (Saale), Germany.
authors.forename: Kathrin
authors.initials: K
authors.lastname: Kowarschik
authors.affiliation: Proteome Analytics, Leibniz Institute of Plant Biochemistry, Halle (Saale) 06120, Germany.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Hoehenwarter
authors.affiliation: Department of Stress and Developmental Biology, Leibniz Institute of Plant Biochemistry, Halle (Saale) 06120, Germany.
authors.forename: Justin
authors.initials: J
authors.lastname: Lee
authors.affiliation: Independent Junior Research Group-Ubiquitination in Immunity, Leibniz Institute of Plant Biochemistry, Halle (Saale) 06120, Germany mtrujillo@ipb-halle.de.|ScienceCampus Halle-Plant-Based Bioeconomy, D-06120 Halle (Saale), Germany.
authors.forename: Marco
authors.initials: M
authors.lastname: Trujillo
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant / Q000235:genetics / Q000502:physiology; D020929:Mitogen-Activated Protein Kinase Kinases / Q000235:genetics / Q000378:metabolism*; D057865:Plant Immunity / Q000235:genetics; D011485:Protein Binding; D015398:Signal Transduction / Q000235:genetics / Q000502:physiology; D044767:Ubiquitin-Protein Ligases / Q000235:genetics / Q000378:metabolism*; D054875:Ubiquitination / Q000235:genetics / Q000502:physiology
chemical_list: D029681:Arabidopsis Proteins; C582896:PUB22 protein, Arabidopsis; D044767:Ubiquitin-Protein Ligases; C458516:AtMPK3 protein, Arabidopsis; D020929:Mitogen-Activated Protein Kinase Kinases