title: Arabidopsis E3 ubiquitin ligase PLANT U-BOX13 (PUB13) regulates chitin receptor LYSIN MOTIF RECEPTOR KINASE5 (LYK5) protein abundance.
abstract: Long-chain chitooligosaccharides are fungal microbe-associated molecular patterns (MAMPs) that are recognized by LYSIN MOTIF RECEPTOR KINASE5 (LYK5), inducing the formation of a complex with CHITIN ELICITOR RECEPTOR KINASE1 (CERK1). Formation of this complex leads to activation of the CERK1 intracellular kinase domain and induction of plant innate immunity in Arabidopsis. We found that addition of chitooctaose induced LYK5 protein accumulation as a result of de novo gene expression and the inhibition of LYK5 protein degradation. Screening the putative E3 ligases for interaction with LYK5 identified PLANT U-BOX13 (PUB13), which complexed with LYK5, but this complex dissociated upon addition of chitooctaose. Consistent with these results, LYK5 protein abundance was higher in pub13 mutants compared with the wild type without chitooctaose treatment, while similar abundance was detected with the addition of chitooctaose. The pub13 mutants showed hypersensitivity to chitooctaose-induced rapid responses, such as the production of reactive oxygen species (ROS) and mitogen-activated protein (MAP) kinase phosphorylation, but exhibited normal responses to subsequent long-term chitooctaose treatment, such as gene expression and callose deposition. In addition, PUB13 could ubiquitinate the LYK5 kinase domain in vitro. Taken together, our results suggest an important regulatory function for the turnover of LYK5 mediated by the E3 ligase PUB13.
authors.affiliation: Institute of Biotechnology, Zhejiang University, Hangzhou, 310058, China.
authors.forename: Dehua
authors.initials: D
authors.lastname: Liao
authors.affiliation: College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China.
authors.forename: Yangrong
authors.initials: Y
authors.lastname: Cao
authors.affiliation: Institute of Biotechnology, Zhejiang University, Hangzhou, 310058, China.
authors.forename: Xun
authors.initials: X
authors.lastname: Sun
authors.affiliation: Divisions of Plant Science and Biochemistry, Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO, 65211, USA.
authors.forename: Catherine
authors.initials: C
authors.lastname: Espinoza
authors.affiliation: Divisions of Plant Science and Biochemistry, Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO, 65211, USA.
authors.forename: Cuong T
authors.initials: CT
authors.lastname: Nguyen
authors.affiliation: Institute of Biotechnology, Zhejiang University, Hangzhou, 310058, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Liang
authors.affiliation: Divisions of Plant Science and Biochemistry, Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO, 65211, USA.
authors.forename: Gary
authors.initials: G
authors.lastname: Stacey
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D002686:Chitin / Q000031:analogs & derivatives / Q000378:metabolism; D048271:Chitosan; D009844:Oligosaccharides / Q000378:metabolism; D000069452:Pathogen-Associated Molecular Pattern Molecules / Q000378:metabolism; D010802:Phylogeny; D030821:Plants, Genetically Modified; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism*; D059748:Proteolysis; D017382:Reactive Oxygen Species / Q000378:metabolism; D014026:Nicotiana / Q000235:genetics; D044767:Ubiquitin-Protein Ligases / Q000235:genetics / Q000378:metabolism*; D054875:Ubiquitination
chemical_list: D029681:Arabidopsis Proteins; D009844:Oligosaccharides; D000069452:Pathogen-Associated Molecular Pattern Molecules; D017382:Reactive Oxygen Species; C525074:chitooctaose; C493484:oligochitosan; D002686:Chitin; D048271:Chitosan; C558942:PUB13 protein, Arabidopsis; D044767:Ubiquitin-Protein Ligases; C000599656:LYK5 protein, Arabidopsis; D011494:Protein Kinases
keywords: CHITIN ELICITOR RECEPTOR KINASE1 (AtCERK1); E3 ligase; LYSIN MOTIF RECEPTOR KINASE5 (AtLYK5); PLANT U-BOX13 (AtPUB13); chitin; microbe-associated molecular pattern (MAMP)-triggered immunity; protein degradation; ubiquitination