Gal-On A, Antignus Y, Rosner A, Raccah B
Department of Virology, Agricultural Research Organization, Bet Dagan, Israel.
J Gen Virol. 1992 Sep;73 ( Pt 9):2183-7. doi: 10.1099/0022-1317-73-9-2183.
An aphid-transmissible (AT) and two non-aphid-transmissible (NAT) isolates of zucchini yellow mosaic virus (ZYMV) were studied. The predicted amino acid sequences of the coat protein (CP) of the three virus isolates were analysed and compared. The NAT isolates differed from the AT isolate in having a Thr instead of an Ala residue at position 10 in the conserved Asp-Ala-Gly triplet in the N-terminal region of CP. Aphid transmissibility was restored in a progeny virus derived from an infectious clone of the ZYMV-NAT isolate in which Thr was changed back to Ala by site-directed mutagenesis. However this mutation did not have any effect on the multiplication rate in squash, which was significantly higher than that of the AT isolate. The involvement of this mutation in aphid transmission and virus multiplication is discussed.
对西葫芦黄花叶病毒（ZYMV）的一种蚜虫传播型（AT）分离株和两种非蚜虫传播型（NAT）分离株进行了研究。分析并比较了三种病毒分离株外壳蛋白（CP）的预测氨基酸序列。NAT分离株与AT分离株的不同之处在于，在CP N端区域保守的Asp-Ala-Gly三联体中，第10位的残基为苏氨酸（Thr）而非丙氨酸（Ala）。在从ZYMV-NAT分离株的感染性克隆衍生而来的子代病毒中，通过定点诱变将苏氨酸变回丙氨酸后，蚜虫传播能力得以恢复。然而，这种突变对南瓜中的增殖率没有任何影响，其增殖率明显高于AT分离株。本文讨论了这种突变在蚜虫传播和病毒增殖中的作用。
