大麦黄矮病毒与介体麦蚜相互识别的分子机理研究

The nucleotide sequences of the coat protein (CP) and readthrough protein (RTP) genes of Chinese GAV isolate of Barley yellow dwarf virus (BYDV) were determined. The CP and RTP genes of GAV isolate comprised 600 and 1374 nucleotides respectively. When the CP and RTP gene sequences of GAV isolate were compared with those of previously reported BYDV isolates, high sequence similarities between the CP gene (97.5%) of MAV-PS1 and GAV isolate were observed, while the RTP gene (87.8%) sequences shared lower. The results of alignment of the deduced amino acid sequences of the RTP gene showed that sequence diversity was localized to the C-terminal, and might explain the observed difference between the transmission phenotype of GAV and NY-MAV. A 50 kDa protein (P50) associated transmission has been identificated in the body of Schizaphis graminum and Sitobion avenae, two aphid vectors transmitting BYDV GAV isolate. P50 in the extracts of S. graminum were isolated by preparation electrophoresis and electro-eluted proteins from the gel slices for antiserum preparation. After feeding the antiserum through membrane, the transmission efficiencies of S. graminum and S. avenae for GAV isolate decreased significantly. It was suggested that P50 should be related with transmission process. To employ electromicroscope immunogold-labeling method for cell ultrastructure localization of p50, it was found that it existed in salivary gland of S. avenae and S. graminum. No labeled proteins were found in the hindgut of two aphid species, as well as R. padi tissues.The ascertainment of the protein associated with virus transmission has a significance influence to further understanding the transmission mechanism and genetic engineering for resistant to vector transmission.

通过对大麦黄矮病毒不同基因产物与介体麦蚜细胞蛋白组分亲和能力测定，确定在传毒过程中参与病毒与介体相互识别的因子，对传毒相关蛋白进行纯化，从分子水平上阐明介体麦蚜的传毒机理。对研究昆虫传毒机制和虫传病毒发生规律具有重要的理论和实践意义，并为抗介体传播的基因工程育种打下坚实的基础。