Husted K
Department of Plant Pathology and Pest Management, Danish Institute of Plant and Soil Science, Lyngby, Denmark.
Virus Genes. 1995;11(1):59-61. doi: 10.1007/BF01701663.
Kalanchoë mosaic potyvirus (KMV) is transmitted by aphids in a nonpersistent manner. After multiple mechanical inoculations, a non-aphid-transmissible (NAT) variant appeared. Addition of purified helper component (HC) from potato virus Y-infected plants did not restore the aphid transmissibility of purified KMV-NAT. Comparison of the nucleotide sequence in the N-terminal half of the coat protein gene of KMV-NAT with that of an aphid-transmissible (AT) KMV strain revealed a single nucleotide difference (G to A). This nucleotide change turns a glycine residue (G) in the KMV-AT isolate into a glutamic acid residue (E) in the KMV-NAT isolate, abolishing the Asp-Ala-Gly (DAG) sequence, which has previously been shown to be essential for aphid transmission. The experiments show that non-aphid transmissibility is most likely caused by the change in the DAG sequence.
伽蓝菜花叶马铃薯Y病毒（KMV）通过蚜虫以非持久性方式传播。经过多次机械接种后，出现了一种非蚜虫传播（NAT）变体。添加来自感染马铃薯Y病毒的植物的纯化辅助成分（HC）并不能恢复纯化的KMV-NAT的蚜虫传播性。将KMV-NAT外壳蛋白基因N端一半的核苷酸序列与蚜虫可传播（AT）的KMV株系的核苷酸序列进行比较，发现有一个单核苷酸差异（G变为A）。这种核苷酸变化将KMV-AT分离株中的甘氨酸残基（G）转变为KMV-NAT分离株中的谷氨酸残基（E），从而消除了天冬氨酸-丙氨酸-甘氨酸（DAG）序列，此前已证明该序列对蚜虫传播至关重要。实验表明，非蚜虫传播性很可能是由DAG序列的变化引起的。
