title: Isolation and characterization of a bread wheat salinity responsive ERF transcription factor.
abstract: A screen conducted on both a suppression subtractive hybridization and a full length cDNA library made from a salinity tolerant bread wheat cultivar SR3 (Triticum aestivum cv. SR3) resulted in the recognition of TaERF4, a gene including both an AP2/ERF domain and a nuclear localization signal. The 982 bp TaERF4 cDNA comprised a 582 bp open reading frame, encoding a 193 residue polypeptide of molecular weight 20 kDa and calculated pI 8.48. A TaERF4-GFP fusion protein localized preferentially to the nuclei of Arabidopsis thaliana protoplasts. TaERF4 is a member of the B-1 group within the ERF sub-family and was not transactivatable in yeast. The presence of an ERF-associated amphiphilic repression (EAR) motif at its C-terminus suggests that TaERF4 is probably a transcription repressor. TaERF4 was inducible by exposure to salinity and osmotic stresses, but not to exogenously supplied abscisic acid (ABA). The heterologous constitutive expression of TaERF4 in Arabidopsis enhanced the level of sensitivity to salinity stress, possibly via the repression of tonoplast Na(+)/H(+) antiporter activity. There was no phenotype associated with the transgene's presence when plants were subjected to either osmotic stress or ABA treatment. TaERF4 appears to be a transcription repressor acting within the ABA-independent response to salinity stress.
authors.affiliation: The Key Laboratory of Plant Cell Engineering and Germplasm Innovation, Ministry of Education, School of Life Sciences, Shandong University, Jinan 250100, PR China.
authors.forename: Wei
authors.initials: W
authors.lastname: Dong
authors.forename: Xinghui
authors.initials: X
authors.lastname: Ai
authors.forename: Fei
authors.initials: F
authors.lastname: Xu
authors.forename: Taiyong
authors.initials: T
authors.lastname: Quan
authors.forename: Shuwei
authors.initials: S
authors.lastname: Liu
authors.forename: Guangmin
authors.initials: G
authors.lastname: Xia
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D001665:Binding Sites / Q000235:genetics; D027682:Cation Transport Proteins / Q000235:genetics / Q000378:metabolism; D018744:DNA, Plant / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D017343:Genes, Plant; D008969:Molecular Sequence Data; D010802:Phylogeny; D010940:Plant Proteins / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D030821:Plants, Genetically Modified; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism; D054712:Salinity; D017386:Sequence Homology, Amino Acid; D017923:Sodium-Hydrogen Exchangers / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D015533:Transcriptional Activation; D014908:Triticum / Q000235:genetics / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; D027682:Cation Transport Proteins; D018744:DNA, Plant; D004268:DNA-Binding Proteins; C117751:NHX1 protein, Arabidopsis; D010940:Plant Proteins; D017923:Sodium-Hydrogen Exchangers; D014157:Transcription Factors; C093680:ethylene-responsive element binding protein