title: An Arabidopsis WDR protein coordinates cellular networks involved in light, stress response and hormone signals.
abstract: The WD-40 repeat (WDR) protein acts as a scaffold for protein interactions in various cellular events. An Arabidopsis WDR protein exhibited sequence similarity with human WDR26, a scaffolding protein implicated in H2O2-induced cell death in neural cells. The AtWDR26 transcript was induced by auxin, abscisic acid (ABA), ethylene (ET), osmostic stress and salinity. The expression of AtWDR26 was regulated by light, and seed germination of the AtWDR26 overexpression (OE) and seedling growth of the T-DNA knock-out (KO) exhibited altered sensitivity to light. Root growth of the OE seedlings increased tolerance to ZnSO4 and NaCl stresses and were hypersensitive to inhibition of osmotic stress. Seedlings of OE and KO altered sensitivities to multiple hormones. Transcriptome analysis of the transgenic plants overexpressing AtWDR26 showed that genes involved in the chloroplast-related metabolism constituted the largest group of the up-regulated genes. AtWDR26 overexpression up-regulated a large number of genes related to defense cellular events including biotic and abiotic stress response. Furthermore, several members of genes functioning in the regulation of Zn homeostasis, and hormone synthesis and perception of auxin and JA were strongly up-regulated in the transgenic plants. Our data provide physiological and transcriptional evidence for AtWDR26 role in hormone, light and abiotic stress cellular events.
authors.affiliation: Department of Bioagricultural Sciences, National Chiayi University, Chiayi, Taiwan. Electronic address: hwchuang@mail.ncyu.edu.tw.
authors.forename: Huey-Wen
authors.initials: HW
authors.lastname: Chuang
authors.affiliation: Department of Bioagricultural Sciences, National Chiayi University, Chiayi, Taiwan.
authors.forename: Ji-Huan
authors.initials: JH
authors.lastname: Feng
authors.affiliation: Department of Bioagricultural Sciences, National Chiayi University, Chiayi, Taiwan.
authors.forename: Yung-Lin
authors.initials: YL
authors.lastname: Feng
authors.affiliation: Department of Bioagricultural Sciences, National Chiayi University, Chiayi, Taiwan.
authors.forename: Miam-Ju
authors.initials: MJ
authors.lastname: Wei
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D047908:Intracellular Signaling Peptides and Proteins / Q000235:genetics* / Q000378:metabolism; D008027:Light; D010937:Plant Growth Regulators / Q000378:metabolism*; D016415:Sequence Alignment; D015398:Signal Transduction; D013312:Stress, Physiological
chemical_list: D029681:Arabidopsis Proteins; C000611293:At5g08560 protein, Arabidopsis; D047908:Intracellular Signaling Peptides and Proteins; D010937:Plant Growth Regulators
keywords: Abiotic stress; Biotic stress; Hormone signaling; Light signaling; WD-40 protein