title: The Arabidopsis tandem CCCH zinc finger proteins AtTZF4, 5 and 6 are involved in light-, abscisic acid- and gibberellic acid-mediated regulation of seed germination.
abstract: Tandem CCCH zinc finger proteins (TZFs) are post-transcriptional regulators of gene expression in animals and yeast. Genetic studies indicate that plant TZFs are involved in hormone-mediated developmental and environmental responses. We have demonstrated previously that Arabidopsis AtTZF1 can localize to processing bodies (PBs) and stress granules (SGs), and affects abscisic acid (ABA)- and gibberellic acid (GA)-mediated growth, stress and gene expression responses. Here we show that AtTZF4, 5 and 6 are specifically expressed in seeds. Consistent with the observation that their expression levels decline during seed imbibition, AtTZF4, 5 and 6 are up-regulated by ABA and down-regulated by GA. Mutant analyses indicate that AtTZF4, 5 and 6 act as positive regulators for ABA- and negative regulators for light- and GA-mediated seed germination responses. Results of gene expression analysis indicate that AtTZF4, 5 and 6 affect seed germination by controlling genes critical for ABA and GA response. Furthermore, AtTZF4, 5 and 6 can co-localize with both PB and SG markers in Arabidopsis cells. Specifically, AtTZF6 can be assembled into PBs and SGs in embryos with the induction of stress hormone methyl jasmonate under the control of native AtTZF6 promoter.
authors: Department of Horticulture and Crop Science, The Ohio State University, Columbus, OH 43210, USA.
authors: Srimathi
authors: S
authors: Bogamuwa
authors: Jyan-Chyun
authors: JC
authors: Jang
mesh_terms: D000040:Abscisic Acid / Q000494:pharmacology; D017360:Arabidopsis / Q000166:cytology / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D003594:Cytoplasmic Granules; D035264:Flowers / Q000166:cytology / Q000187:drug effects / Q000235:genetics / Q000502:physiology; D018506:Gene Expression Regulation, Plant; D017930:Genes, Reporter; D018525:Germination; D005875:Gibberellins / Q000494:pharmacology; D008954:Models, Biological; D009154:Mutation; D009928:Organ Specificity; D057445:Plant Dormancy; D010937:Plant Growth Regulators / Q000494:pharmacology*; D018515:Plant Leaves / Q000166:cytology / Q000187:drug effects / Q000235:genetics / Q000502:physiology; D030821:Plants, Genetically Modified; D036226:Seedlings / Q000166:cytology / Q000187:drug effects / Q000235:genetics / Q000502:physiology; D012639:Seeds / Q000166:cytology / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D016335:Zinc Fingers
chemical_list: D000040:Abscisic Acid; D029681:Arabidopsis Proteins; D005875:Gibberellins; D010937:Plant Growth Regulators; D014157:Transcription Factors; C586036:TZF4 protein, Arabidopsis; C586037:TZF5 protein, Arabidopsis; C007842:gibberellic acid; C111376:At5g07500 protein, Arabidopsis
keywords: ABA; GA; PBs; SGs; TZF; processing bodies; stress granules