title: A Role of the FUZZY ONIONS LIKE Gene in Regulating Cell Death and Defense in Arabidopsis.
abstract: Programmed cell death (PCD) is critical for development and responses to environmental stimuli in many organisms. FUZZY ONIONS (FZO) proteins in yeast, flies, and mammals are known to affect mitochondrial fusion and function. Arabidopsis FZO-LIKE (FZL) was shown as a chloroplast protein that regulates chloroplast morphology and cell death. We cloned the FZL gene based on the lesion mimic phenotype conferred by an fzl mutation. Here we provide evidence to support that FZL has evolved new function different from its homologs from other organisms. We found that fzl mutants showed enhanced disease resistance to the bacterial pathogen Pseudomonas syringae and the oomycete pathogen Hyaloperonospora arabidopsidis. Besides altered chloroplast morphology and cell death, fzl showed the activation of reactive oxygen species (ROS) and autophagy pathways. FZL and the defense signaling molecule salicylic acid form a negative feedback loop in defense and cell death control. FZL did not complement the yeast strain lacking the FZO1 gene. Together these data suggest that the Arabidopsis FZL gene is a negative regulator of cell death and disease resistance, possibly through regulating ROS and autophagy pathways in the chloroplast.
authors.affiliation: Department of Biological Sciences, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21250, USA.
authors.forename: Arianne
authors.initials: A
authors.lastname: Tremblay
authors.affiliation: Department of Biological Sciences, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21250, USA.
authors.forename: Savanna
authors.initials: S
authors.lastname: Seabolt
authors.affiliation: State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, P.R. China.
authors.forename: Hongyun
authors.initials: H
authors.lastname: Zeng
authors.affiliation: Department of Biological Sciences, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21250, USA.
authors.forename: Chong
authors.initials: C
authors.lastname: Zhang
authors.affiliation: Institut für Zellbiologie, Universität Bayreuth, Bayreuth 95440, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Böckler
authors.affiliation: Department of Biological Sciences, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21250, USA.
authors.forename: Dominique N
authors.initials: DN
authors.lastname: Tate
authors.affiliation: Department of Biological Sciences, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21250, USA.
authors.forename: Vy Thuy
authors.initials: VT
authors.lastname: Duong
authors.affiliation: State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, P.R. China.
authors.forename: Nan
authors.initials: N
authors.lastname: Yao
authors.affiliation: Department of Biological Sciences, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21250, USA.
authors.forename: Hua
authors.initials: H
authors.lastname: Lu
mesh_terms: D017360:Arabidopsis / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000235:genetics*; D001343:Autophagy; D016923:Cell Death; D002736:Chloroplasts / Q000502:physiology*; D020558:GTP Phosphohydrolases / Q000235:genetics*; D018506:Gene Expression Regulation, Plant; D009154:Mutation / Q000235:genetics; D044742:Peronospora / Q000276:immunology*; D010641:Phenotype; D010935:Plant Diseases / Q000276:immunology*; D057865:Plant Immunity; D018515:Plant Leaves / Q000378:metabolism; D044224:Pseudomonas syringae / Q000276:immunology*; D017382:Reactive Oxygen Species / Q000378:metabolism; D020156:Salicylic Acid / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D017382:Reactive Oxygen Species; C000588570:FZL protein, Arabidopsis; D020558:GTP Phosphohydrolases; D020156:Salicylic Acid