Molecular characterization and expression analysis of WRKY family genes in Dendrobium officinale
The WRKY family of transcription factors is one of the most important families of plant transcriptional regulators, and the members regulate multiple biological processes. However, there is limited information on WRKYs in Dendrobium officinale. In this study, 52 WRKY family genes of D. officinale were surveyed for the first time. Conserved domain, phylogenetic, exon–intron construction, and expression analyses were performed for the DoWRKY genes. Two major types of intron splicing (PR and VQR introns) were found, and the intron insertion position was observed to be relatively conserved in the conserved DoWRKY domains. The expression profiles of nine DoWRKYs were analyzed in cold- and methyl jasmonate (MeJA)-treated D. officinale seedlings; the DoWRKYs showed significant expression changes at different levels, which suggested their vital roles in stress tolerance. Moreover, the expression trends of most of the DoWRKYs after the simultaneous cold stress and MeJA treatment were the opposite of those of DoWRKYs after the individual cold stress and MeJA treatments, suggesting that the two stresses might have antagonistic effects and affect the adaptive capacity of the plants to stresses. Twelve DoWRKY genes were differentially expressed between symbiotic and asymbiotic germinated seeds; all were upregulated in the symbiotic germinated seeds except DoWRKY16. These differences in expression of DoWRKYs might be involved in promoting in vitro symbiotic germination of seeds with Tulasnella-like fungi. Our findings will be useful for further studies on the WRKY family genes in orchids.
KeywordsWRKY Dendrobium officinale Gene family Abiotic stress Symbiotic germination seeds
This work was supported by grants from the National High Technology Research and Development Program of China (863 Program) (No. 2013AA102607).
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest. Tao Wang declares that she has no conflict of interest. Zheng Song declares that he has no conflict of interest. Li Wei declares that she has no conflict of interest. Lubin Li declares that he has no conflict of interest.
This article does not contain any studies with human subjects or animals performed by any of the authors.
- Bencke-Malato M, Cabreira C, Wiebke-Strohm B, Bücker-Neto L, Mancini E, Osorio MB, Homrich MS, Turchetto-Zolet AC, De Carvalho MC, Stolf R et al (2014) Genome-wide annotation of the soybean WRKY family and functional characterization of genes involved in response to Phakopsora pachyrhizi infection. BMC Plant Biol 14:236CrossRefPubMedPubMedCentralGoogle Scholar
- Consortium TIBG (2012) A physical, genetic and functional sequence assembly of the barley genome. Nature 491:711–717Google Scholar
- Dou F, Xuan W, Huang Z, Deng F, Tan X (2009) Effects of MeJA on cold tolerance of banana seedlings. J Fruit Sci 26:390–393Google Scholar
- Duan X, Deng Z, Bin J (2009) Efects of Methyl Jasmonate on cold resistance of rice (Oryza sativa L.) seedlings. Plant Physiol Commun 45:881–884Google Scholar
- Jiang Y, Zhu Y, Gao Y, Si J (2016) Cloning and expression analysis of WRKY5 gene in Dendrobium officinale. Chin Tradit Herbal Drugs 47:301–308Google Scholar
- Mangelsen E, Kilian J, Berendzen KW, Kolukisaoglu ÜH, Harter K, Jansson C, Wanke D (2008) Phylogenetic and comparative gene expression analysis of barley (Hordeum vulgare) WRKY transcription factor family reveals putatively retained functions between monocots and dicots. BMC Genomics 9:194CrossRefPubMedPubMedCentralGoogle Scholar
- Qi F, Li J, Duan L, Li Z (2006) Inductions of coronatine and MeJA to low-temperature resistance of wheat seedlings. Acta Bot Boreal-Occident Sin 26:1776–1780Google Scholar
- Rao G, Sui J, Zhang J (2015) In silico genome-wide analysis of the WRKY gene family in Salix Arbutifolia. Plant Omics 4:353–360Google Scholar
- Rossberg M, Theres K, Acarkan A, Herrero R, Schmitt T, Schumacher K, Schmitz G, Schmidt R (2001) Comparative sequence analysis reveals extensive microcolinearity in the lateral suppressor regions of the tomato, Arabidopsis, and Capsella genomes. Plant cell 13:979–988CrossRefPubMedPubMedCentralGoogle Scholar
- Tang J, Wang F, Hou X, Wang Z, Huang Z (2013) Genome-wide fractionation and identification of WRKY transcription factors in Chinese cabbage (Brassica rapa ssp. pekinensis) reveals collinearity and their expression patterns under abiotic and biotic stresses. Plant Mol Biol Rep 32:781–795CrossRefGoogle Scholar
- Wang C (2013) Cloning and preliminary function analysis of DnWRKY29 gene. Dissertation, Hangzhou Normal UniversityGoogle Scholar
- Xu L, Tian JN, Wang T, Li LB (2017) Symbiosis established between orchid and Tulasnella spp. Fungi. China J Nucl Agric Sci 31:0876–0883Google Scholar
- Zhang Y, Feng JC (2014) Identification and characterization of the grape WRKY Family. Biomed Res Int 2014:1–14Google Scholar
- Zhang G, Zhao MM, Zhang Dw, Guo SX (2013) Reference gene selection for real-time quantitative PCR analysis of Dendrobium officinale. Chin Pharm J 48:1664–1668Google Scholar
- Zhang J, He C, Wu K, Silva JATD, Zeng S, Zhang X, Yu Z, Xia H, Duan J (2016b) Transcriptome analysis of Dendrobium officinale and its application to the identification of genes associated with polysaccharide synthesis. Front Plant Sci 5:1–14Google Scholar
- Zhao J, Meng CC, Zhao YF, Wang CX, Fan HH, Jin Q, Li DH, Lin Y, Cai YP (2015a) Cloning and expression analysis of transcription factor gene (DoWRKY2) in Dendrobium officinal. J Agr Biotechnol 23:1049–1057Google Scholar
- Zhao J, Sun SW, Meng CC, Jin Q, Fan HH, Lin Y, Cai YP (2015b) Cloning and expression analysis of transcription factor gene DoWRKY1 in Dendrobium officinal. China J Chin Materia Med 40:2807–2813Google Scholar
- Zou Q, Zhu K, Liu H, Zhou J, Ma G (2011) Effect of exogenous Methyl Jasmonate on chlorophyll fluorescence and antioxidant characteristics in the leaves of phalaenopsis amabilis under abiotic stress. J Plant Physiol 47:913–917Google Scholar