ABSTRACT
Objective: To clone eight members of WRKY of transcription factor family in Camellia sinensis, and analyze their bioinformatics and expression under abiotic stress. Methods: Eight WRKY transcription factor genes were cloned from Tieguanyin cultivar by RT-PCR, and the physicochemical properties of the eight WRKY protein were analyzed by bioinformatics Methods:. At the same time, the establishment of phylogenetic tree, comparison of multiple sequences, and analysis of conserved motifs were carried out by comparing WRKY of C. sinensis with homologous genes of Arabidopsis thaliana. Quantitative real-time PCR (qRT-PCR) was used to detect the expression of eight WRKY genes under low temperature, drought, and ABA stress treatment. Results: The ORF lengths of eight WRKY genes were 1 407, 2 208, 1 302, 849, 978, 879, 1 443, and 810 bp, encoding 468, 735, 433, 282, 325, 292, 480, and 269 amino acids, respectively. GenBank accession numbers were MG298951, MG298952, MG298955, MG298956, MG298957, MG298959, MG298960, and MG298963, respectively. Phylogenetic tree and sequence alignment analysis showed that eight CsWRKYs could be divided into two groups and contained WRKYGQK conserved domain and zinc finger structures, except that CsWRKY39 lacked zinc finger structure. The expression pattern of CsWRKYs was induced under the condition of low temperature, drought, and ABA stress. The expression of CsWRKY2, CsWRKY21, CsWRKY23, CsWRKY44 and CsWRKY65 increased to more than 2 after low temperature treatment with significant response to low temperature stress. The expression of CsWRKY21, CsWRKY23, CsWRKY3,9 and CsWRKY65 was up-regulated under 12 h of drought stress and 6 h of ABA treatment. This result indicated that CsWRKYs might be closely related to stress response in C. sinensis. Conclusion: Eight CsWRKY genes from different groups were cloned, and this result indicated that CsWRKYs might be closely related to stress response in C. sinensis.
ABSTRACT
Objective To identify the genes of WRKY transcription factors (TFs) from roots of Bupleurum chinense and genes that potentially regulate saikosaponin (SS) biosynthesis. Methods Firstly, the subfamily cluster analysis was mainly based on Arabidopsis thaliana WRKYs for 27 putative WRKY TFs selected from previous transcriptome sequencing data. Secondly, qPCR was used to screen such genes of WRKY TFs that could be induced by NaCl and PEG6000 in adventitious roots of B. chinense. Meanwhile, saikosaponins (SSs) in treated adventitious roots were determined by HPLC. The roots were collected at 0, 2, 4, 8, 12, 24, 48, and 72 h after treatments, and 120 h only for PEG. Finally, the tissue-specific expression was analyzed on screened genes by qPCR. Results The 27 genes were grouped into three categories: There were nine in Group I, 15 in Group II, and two in Group III. Four genes of WRKYTFs, BCWRKY6, BCWRKY16, BCWRKY32, and BCWRKY35 were obviously induced by NaCl in adventitious roots of B. chinense, while only BCWRKY32 was induced by PEG. The content of SSs increased at different levels in NaCl and PEG6000 treatment. Three genes including BCWRKY6, BCWRKY32, and BCWRKY35, expressed most in roots, were similar to the accumulation pattern of SS. Conclusion The three WRKY genes, BCWRKY6, BCWRKY32, and BCWRKY35, may be involved in the biosynthesis of SS.
ABSTRACT
WRKY transcription factor is one of the most important transcription factor families widely existing in higher plants, which playing critical role in plant morphogenesis, development, biotic (including phytopathogens, pests etc.) and abiotic (drought, salt, chilling, high temperature, etc.) stress. In the present work, primers used to amplify full-length gene encoding WRKY transcription factor were designed based on the transcriptome data of P. ginseng that induced by benzoic acid, one of the most important autotoxins identified from root exudates and rhizosphere soil of P. ginseng. Then, a WRKY gene, temporarily named as WRKY7, was confirmed by RT-RCR. Furthermore, sequencing and sequence analysis of WRKY7 was conducted. Results indicated that, the full length cDNA of WRKY7 was 1 216 bp, the open reading frame (ORF) of which was 1 014 bp, encodes 337 amino acids. Homologous analysis and phylogenetic tree showed that, WRKY7 belonged to the Ⅲ category of WRKY families, which showing 87% similarity to WRKY6 in P. quinquefolius. Real-time PCR results showed that the expression of WRKY7 in P. ginseng induced by benzoic acid was up-regulated markedly than the control, so we speculated that WRKY7 was involved in the response to benzoic acid stress, which will be helpful for further research on the molecular mechanism of ginseng plant response to benzoic acid stress.