title: bZIP transcription factor OsbZIP52/RISBZ5: a potential negative regulator of cold and drought stress response in rice.
abstract: OsbZIP52/RISBZ5 is a member of the basic leucine zipper (bZIP) transcription factor (TF) family in rice (Oryza sativa) isolated from rice (Zhonghua11) panicles. Expression of the OsbZIP52 gene was strongly induced by low temperature (4°C) but not by drought, PEG, salt, or ABA. The subcellular localization of OsbZIP52-GFP in onion (Allium cepa) epidermis cells revealed that OsbZIP52 is a nuclear localized protein. A transactivation assay in yeast demonstrated that OsbZIP52 functions as a transcriptional activator and can specifically bind to the G-box promoter motif. In a yeast two-hybrid (Y-2-H) experiment, OsbZIP52 was able to form homodimeric complexes. Rice plants overexpressing OsbZIP52 showed significantly increased sensitivity to cold and drought stress. Real-time PCR analysis revealed that some abiotic stress-related genes, such as OsLEA3, OsTPP1, Rab25, gp1 precursor, β-gal, LOC_Os05g11910 and LOC_Os05g39250, were down-regulated in OsbZIP52 overexpression lines. These results suggest that OsbZIP52/RISBZ5 could function as a negative regulator in cold and drought stress environments.
authors.affiliation: Key Laboratory of Cell Proliferation and Regulation of Ministry of Education, College of Life Sciences, Beijing Normal University, Beijing 100875, People's Republic of China.
authors.forename: Citao
authors.initials: C
authors.lastname: Liu
authors.forename: Yanbin
authors.initials: Y
authors.lastname: Wu
authors.forename: Xiping
authors.initials: X
authors.lastname: Wang
mesh_terms: D000040:Abscisic Acid / Q000494:pharmacology; D000595:Amino Acid Sequence; D050976:Basic-Leucine Zipper Transcription Factors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001681:Biological Assay; D002467:Cell Nucleus / Q000187:drug effects / Q000378:metabolism; D003080:Cold Temperature; D015536:Down-Regulation / Q000187:drug effects / Q000235:genetics; D055864:Droughts; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D008969:Molecular Sequence Data; D059372:Nucleotide Motifs / Q000235:genetics; D012275:Oryza / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D010802:Phylogeny; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D011401:Promoter Regions, Genetic / Q000235:genetics; D011485:Protein Binding / Q000187:drug effects; D055503:Protein Multimerization / Q000187:drug effects; D012441:Saccharomyces cerevisiae / Q000378:metabolism; D036226:Seedlings / Q000187:drug effects / Q000235:genetics; D013312:Stress, Physiological / Q000187:drug effects / Q000235:genetics; D015533:Transcriptional Activation / Q000187:drug effects / Q000235:genetics
chemical_list: D050976:Basic-Leucine Zipper Transcription Factors; D010940:Plant Proteins; D000040:Abscisic Acid