title: Overexpression of a phytochrome-regulated tandem zinc finger protein gene, OsTZF1, confers hypersensitivity to ABA and hyposensitivity to red light and far-red light in rice seedlings.
abstract: Tandem zinc finger proteins (TZFs) in plants are involved in gene regulation, developmental responses, and hormone-mediated environmental responses in Arabidopsis. However, little information about the functions of the TZF family in monocots has been reported. Here, we investigated a cytoplasmic TZF protein, OsTZF1, which is involved in photomorphogenesis and ABA responses in rice seedlings. The OsTZF1 gene was expressed at relatively high levels in leaves and shoots, although its transcripts were detected in various organs. Red light (R)- and far-red light (FR)-mediated repression of OsTZF1 gene expression was attributed to phytochrome B (phyB) and phytochrome C (phyC), respectively. In addition, OsTZF1 expression was regulated by salt, PEG, and ABA. Overexpression of OsTZF1 caused a long leaf sheath relative to wild type (WT) under R and FR, suggesting that OsTZF1 probably acts as a negative regulator of photomorphogenesis in rice seedlings. Moreover, ABA-induced growth inhibition of rice seedlings was marked in the OsTZF1-overexpression lines compared with WT, suggesting the positive regulation of OsTZF1 to ABA responses. Genome-wide expression analysis further revealed that OsTZF1 also functions in other hormone or stress responses. Our findings supply new evidence on the functions of monocot TZF proteins in phytochrome-mediated light and hormone responses.
  
  
  CONCLUSIONS
  OsTZF1 encodes a cytoplasm-localized tandem zinc finger protein and is regulated by both ABA and phytochrome-mediated light signaling. OsTZF1 functions in phytochrome-mediated light and ABA responses in rice.
authors.affiliation: High-Tech Research Center, Shandong Academy of Agricultural Sciences, Jinan 250100, People's Republic of China.
authors.forename: Cheng
authors.initials: C
authors.lastname: Zhang
authors.forename: Fang
authors.initials: F
authors.lastname: Zhang
authors.forename: Jinjun
authors.initials: J
authors.lastname: Zhou
authors.forename: Zhongxue
authors.initials: Z
authors.lastname: Fan
authors.forename: Fan
authors.initials: F
authors.lastname: Chen
authors.forename: Huiquan
authors.initials: H
authors.lastname: Ma
authors.forename: Xianzhi
authors.initials: X
authors.lastname: Xie
mesh_terms: D000040:Abscisic Acid / Q000494:pharmacology*; D000595:Amino Acid Sequence; D018506:Gene Expression Regulation, Plant; D008027:Light; D008969:Molecular Sequence Data; D012275:Oryza / Q000187:drug effects / Q000235:genetics* / Q000528:radiation effects; D010834:Phytochrome / Q000378:metabolism*; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D030821:Plants, Genetically Modified / Q000187:drug effects / Q000235:genetics / Q000528:radiation effects; D036226:Seedlings / Q000187:drug effects / Q000254:growth & development / Q000528:radiation effects*; D014170:Transformation, Genetic; D016335:Zinc Fingers
chemical_list: D010940:Plant Proteins; D010834:Phytochrome; D000040:Abscisic Acid