甘蓝型油菜BnEIN3基因的克隆及菌核病诱导表达研究

乙烯不敏感转录调节基因（EIN3）是定位于细胞核上的乙烯信号转导下游元件，其作为转录因子启动一系列转录级联反应，从而激活乙烯诱导的防御相关基因的表达。拟南芥EIN3功能缺失突变体表现出对死体营养型病原菌高度敏感，表明该基因在抗死体营养型病原菌中发挥一定作用。为克隆甘蓝型油菜EIN3（BnEIN3）基因，该研究采用荧光定量PCR研究菌核病不同抗性的油菜品种接种核盘菌后，BnEIN3的表达变化及差异，初步探讨了BnEIN3在油菜菌核病防卫反应中的作用。

Cloning of Brassica napus EIN3 Gene and Its Expression Induced by Sclerotinia sclerotiorum

Objective] The study was to investigate roles of Brassica napus EIN3 in (BnEIN3) resistance to Sclerotinia sclerotiorum. Methods] Genomic PCR and RT-PCR were carried out to isolate genomic DNA and cDNA sequences of BnEIN3 from oilseed rape, based on the highly conserved region of EIN3 gene from Arabidopsis thaliana and the homologous sequences of oilseed rape ESTs. Expression levels of BnEIN3 were detected in three varieties of oilseed rape inoculated with S.sclerotiorum by real-time quantitative PCR. Results]A 1 947 bp DNA fragment was obtained from oilseed rape. The fragment shared 82% identity to A. thaliana EIN3, encoded 614 amino acids containing an EIN3 domain, and was named as BnEIN3. Real-time PCR results showed that expression patterns of BnEIN3 were drastically different in different varieties. In highly resistant oilseed rape variety D083, BnEIN3 expression level was significantly increased 72 h after S.sclerotiorum inoculation whereas in middle resistant and susceptible varieties Zhongshuang 9 and 84039, BnEIN3 expression was suppressed. Conclusion] BnEIN3 may play an important role in oilseed rape resistance to S.sclerotiorum.