Institute of Bioinformatics and Structural Biology & Department of Life Science, National Tsing Hua University, No. 101 Sec. 2 Kuang Fu Road, Hsinchu, Taiwan.
J Plant Physiol. 2011 Mar 1;168(4):375-81. doi: 10.1016/j.jplph.2010.07.006. Epub 2010 Aug 21.
Three novel ethylene response factor (ERF) genes, BkERF1, BkERF2.1 and BkERF2.2, were isolated from a medicinal plant, Bupleurum kaoi. The deduced BkERFs contain a canonical nuclear localization signal and an ERF/AP2 DNA binding domain. RNA gel blot analysis revealed that BkERF1 and BkERF2.1 were ubiquitously expressed at low levels in all parts of mature plants, and that BkERF2.2 was expressed at moderate levels in vegetative tissues. Exogenous application of methyl jasmonate induced BkERF1/2.1/2.2 transcripts. BkERF2.2 transcript levels were slightly increased by addition of ethephon and salicylic acid. BkERFs were localized in the plant nucleus and functioned as transcriptional activators. In B. kaoi cells overexpressing BKERFs, inoculation with Botrytis cinerea increased expression of some defense genes which are associated with enhanced disease resistance. Similarly, overexpression of BkERFs in transgenic Arabidopsis thaliana resulted in elevated mRNA levels of the defense gene PDF1.2, and in enhanced resistance to B. cinerea. Collectively, these results provide evidence that BkERFs mediate the expression of defense-related genes in plants.
从药用植物柴胡中分离得到了三个新的乙烯响应因子（ERF）基因，BkERF1、BkERF2.1 和 BkERF2.2。推导的 BkERFs 包含一个典型的核定位信号和一个 ERF/AP2 DNA 结合域。RNA 凝胶印迹分析显示，BkERF1 和 BkERF2.1 在成熟植物的所有部位均低水平广泛表达，而 BkERF2.2 在营养组织中中度表达。茉莉酸甲酯的外源应用诱导 BkERF1/2.1/2.2 转录物的表达。乙膦和水杨酸的添加略微增加了 BkERF2.2 转录物的水平。BkERFs 定位于植物细胞核内，并作为转录激活因子发挥作用。在过表达 BKERFs 的柴胡细胞中，接种灰葡萄孢菌会增加一些与增强抗病性相关的防御基因的表达。同样，在拟南芥转基因植物中过表达 BkERFs 会导致防御基因 PDF1.2 的 mRNA 水平升高，并增强对灰葡萄孢菌的抗性。总的来说，这些结果提供了证据表明 BkERFs 介导植物中防御相关基因的表达。
