月季抗白粉病基因RhMLO的亚细胞定位及功能分析

MLO是一类新发现的抗病基因,一些双子叶植物隐性突变的mlo基因使其获得了广谱高抗的抗病性。通过生物信息学分析结合亚细胞定位试验,对前期克隆获得的月季MLO进行亚细胞定位,结果表明,RhMLO1和RhMLO2均为主要分布于细胞质膜、液泡膜和细胞核的跨膜蛋白,与预测结果相符。构建了RhMLO1的正义表达载体,通过农杆菌介导法对月季‘白玉’植株体细胞胚进行遗传转化。利用PCR法和荧光定量PCR法对转基因植株进行分子检测,表明基因已经整合到转基因植株中。分别利用离体鉴定法和显微镜观察法对转基因植株和对照植株进行对白粉病菌(Podosphera pannosa)抗性鉴定,结果一致显示:正义载体的导入降低了转基因植株对白粉病的抗性。

Subcellular Localization and Functional Analysis of Powdery Mildew Resistance Gene MLO in Rose

Mildew resistance locus o (MLO) genes are new type of disease resistance.In dicots,loss-of-function mutations in MLO genes confer high levels of broad-spectrum resistance in powdery mildew.In this study,we analyzed subcellular localization of MLO genes from rose using bioinformatics software combined with subcellular localization experiment.The results showed that RhMLO1 and RhMLO2 were both transmembrane proteins mainly distributed in plasma membrane,vacuole membrane and nucleus,which were basically in line with the prediction.We constructed the plant expression vector with sense RhMLO1 gene based on digestion and connection methods,which was introduced into embryogenic callus of'Baiyu'by Agrobacterium-meidiated transformation.The transgenic lines were confirmed integration based on PCR and FQ-PCR.We compared the difference of powdery mildew resistance level between control plants and transgenic plants by isolated identification and microscope observation.The results showed that RhMLO1-transgenic lines decreased resistance against the pathogen.