摘要
选择对赤霉病菌具有高度特异性和亲合力的单链抗体,与植物防御素构建成融合蛋白基因,将融合蛋白及防御素基因分别与细菌表达载体pGEX和植物表达载体pMBL4构建成重组载体,在细菌中经IPTG诱导表达GST融合蛋白,亲和层析纯化蛋白;经根癌农杆菌介导的真空渗入法在烟草叶片中瞬间表达,提取叶片总蛋白用于鉴定。抑菌活性分析表明,烟草叶片瞬间表达的防御素和抗体-防御素融合蛋白,均对赤霉病菌有强烈的抑菌作用;从细菌中纯化的防御素蛋白,也能有效抑制赤霉病菌生长。说明赤霉病菌抗体-防御素融合蛋白基因,可作为抗赤霉病资源,用于改良植物的抗赤霉病性。
An single-chain antibody gene with a high specificity and affinity to wheat scab fungus was selected to construct a fusion gene with a plant defensin sequence. The antibody-defensin fusion gene and defensin gene alone were cloned into bacterial expression vector pGEX and plant expression vector pMBL, respectively. Bacterial expression was induced upon addition with IPTG, and the antibody-defensin fusion and defensin protein as GST fusions were affinity-purified. Both the antibody-defensin fusion and defensin protein were transiently expressed in tobacco leaves via vacuum infiltration of Agrobacterium tumefaciens. Antifungal assays of total proteins extracted from infiltrated tobacco leaves revealed that the antibody-defensin fusion and defensin proteins displayed a clear inhibitory effect on the fungal growth of wheat scab fungus in vitro. The defensin protein affinity-purified from bacteria also inhibited this fungus. This result indicated that the antibody-defensin fusion constructed in this study could be used as resistance germplasm for genetically improving resistance of plants to this fungus.
出处
《华中农业大学学报》
CAS
CSCD
北大核心
2007年第4期435-438,共4页
Journal of Huazhong Agricultural University
基金
国家自然科学基金项目(304709291
30530510)
科技部"十一五"支撑计划项目(2006BAK02A12)资助
关键词
小麦赤霉病菌
防御素
抗体融合蛋白
抑菌活性
wheat scab fungus
defensin
antibody fusion protein
antifungal activity
