title: Monoubiquitination of histone 2B at the disease resistance gene locus regulates its expression and impacts immune responses in Arabidopsis.
abstract: Disease resistance (R) genes are key components in plant immunity. Here, we show that Arabidopsis (Arabidopsis thaliana) E3 ubiquitin ligase genes HISTONE MONOUBIQUITINATION1 (HUB1) and HUB2 regulate the expression of R genes SUPPRESSOR OF npr1-1, CONSTITUTIVE1 (SNC1) and RESISTANCE TO PERONOSPORA PARASITICA4. An increase of SNC1 expression induces constitutive immune responses in the bonzai1 (bon1) mutant, and the loss of HUB1 or HUB2 function reduces SNC1 up-regulation and suppresses the bon1 autoimmune phenotypes. HUB1 and HUB2 mediate histone 2B (H2B) monoubiquitination directly at the SNC1 R gene locus to regulate its expression. In addition, SNC1 and HUB1 transcripts are moderately up-regulated by pathogen infection, and H2B monoubiquitination at SNC1 is enhanced by pathogen infection. Together, this study indicates that H2B monoubiquitination at the R gene locus regulates its expression and that this histone modification at the R gene locus has an impact on immune responses in plants.
authors.affiliation: State Ministry of Education Key Laboratory of Integrated Management of Crop Pathogens and Insect Pests, Nanjing Agricultural University, Jiangsu 210095, China.
authors.forename: Baohong
authors.initials: B
authors.lastname: Zou
authors.forename: Dong-Lei
authors.initials: DL
authors.lastname: Yang
authors.forename: Zhenying
authors.initials: Z
authors.lastname: Shi
authors.forename: Hansong
authors.initials: H
authors.lastname: Dong
authors.forename: Jian
authors.initials: J
authors.lastname: Hua
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development / Q000276:immunology; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D060467:Disease Resistance / Q000235:genetics*; D018506:Gene Expression Regulation, Plant; D056426:Genetic Loci; D006657:Histones; D005810:Multigene Family; D009154:Mutation / Q000235:genetics; D010641:Phenotype; D010935:Plant Diseases / Q000235:genetics / Q000276:immunology; D057865:Plant Immunity / Q000235:genetics*; D044224:Pseudomonas syringae / Q000502:physiology; D013489:Suppression, Genetic; D019076:Transgenes; D044767:Ubiquitin-Protein Ligases / Q000235:genetics* / Q000378:metabolism; D054875:Ubiquitination
chemical_list: D029681:Arabidopsis Proteins; C000593208:H2B protein, Arabidopsis; D006657:Histones; D044767:Ubiquitin-Protein Ligases