Wang Tao, Song Zheng, Wei Li, Li Lubin
State Key Laboratory of Forest Genetics and Tree Breeding, Key Laboratory of Silviculture of the State Forestry Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, 100091, China.
Environmental Monitoring Center of Handan, Handan, 056002, China.
Genes Genomics. 2018 Mar;40(3):265-279. doi: 10.1007/s13258-017-0602-z. Epub 2017 Nov 17.
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.
WRKY转录因子家族是植物转录调控因子中最重要的家族之一，其成员调控多种生物学过程。然而，关于铁皮石斛中WRKY的信息有限。在本研究中，首次对52个铁皮石斛WRKY家族基因进行了调查。对DoWRKY基因进行了保守结构域、系统发育、外显子-内含子结构及表达分析。发现了两种主要类型的内含子剪接（PR和VQR内含子），且在保守的DoWRKY结构域中观察到内含子插入位置相对保守。分析了9个DoWRKY在冷处理和茉莉酸甲酯（MeJA）处理的铁皮石斛幼苗中的表达谱；DoWRKY在不同水平上表现出显著的表达变化，这表明它们在胁迫耐受性中起着重要作用。此外，冷胁迫和MeJA同时处理后，大多数DoWRKY的表达趋势与单独冷胁迫和MeJA处理后的DoWRKY相反，这表明两种胁迫可能具有拮抗作用，并影响植物对胁迫的适应能力。12个DoWRKY基因在共生萌发种子和非共生萌发种子之间存在差异表达；除DoWRKY16外，所有基因在共生萌发种子中均上调。DoWRKYs的这些表达差异可能参与促进与类土传霉菌的种子体外共生萌发。我们的研究结果将有助于进一步研究兰花中的WRKY家族基因。
