Abstract：WRKY transcription factors are novel transcriptional regulatory factors, which were found to be involved in regulating plant development, metabolism and other physiological processes in recent years. In this study, a new Dendrobium officinale WRKY transcription factor, designated as DoWRKY2 was cloned(GenBank Accession No. KF953910). The full-length cDNA was of 1 309 bp with a 999 bp of open reading frame (ORF), encoding a protein of 332 amino acid residues, and its domain had typical structural features of WRKY family, with four β-sheets. Bioinformatics analysis demonstrated that DoWRKY2 shared the highest similarity with PdWRKY17 of Phoenix dactylifera, which achieved 66%. It had a special motif of HARF, in addition, cluster analysis by phylogenetic tree revealed that it belonged toⅡd subfamily, and shared closest evolutionary relationship with AtWRKY11 and AtWRKY17. It could be expressed in Escherichia coli stably by prokaryotic expression. The results of quantitative Real-time PCR (qRT-PCR) analysis suggested that DoWRKY2 expressed in root, stem, leaf and protocorm-like bodies, with a highest level in leaf and lowest in stem. Also, DoWRKY2 could be response to induction of methyl jasmonate (MeJA) and chitosan, and reached peak at 4 and 1 h, respectively. The research results provide basic materials for further function alanalysis of this gene in the future.
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