Gustafson G D, Larkins B A, Jackson A O
Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana 47907, USA.
Virology. 1981 Jun;111(2):579-87. doi: 10.1016/0042-6822(81)90359-7.
Proteins synthesized in a wheat germ system containing RNA from the Type or ND18 strain of barley stripe mosaic virus (BSMV), or polyribosomes from Type or ND18-infected barley, were compared with each other and with polypeptides from Type and ND18-infected plants. Polypeptides with apparent molecular weights (Mr) of 25, 67, and 120 x 10(3) that were induced in infected barley were synthesized in vitro by polyribosomes from infected plants or RNA from purified BSMV. The 25,000 Mr polypeptide was identified as BSMV coat protein by coelectrophoresis with coat protein from purified virions, by immunoprecipitation, and by absence of [35S]methionine incorporation into the protein. Strain-specific differences were observed in two additional translation products synthesized in both wheat germ and reticulocyte lysate systems containing Type of ND18 RNA. RNAs from both strains directed synthesis of 71 and 82 x 10(3) Mr polypeptides. However, ND18 RNA directed synthesis of a larger amount of the 71,000 Mr polypeptide, whereas with Type RNA the 82,000 Mr polypeptide predominated. These two proteins may be processed in vivo because reduced synthesis of both polypeptides in wheat germ extracts containing polyribosomes from infected plants was correlated with increased synthesis of the 67,000 Mr polypeptide. Several additional polypeptides synthesized in the wheat germ system were probably premature termination products because their synthesis in the reticulocyte lysate was greatly reduced.
将在含有来自大麦条纹花叶病毒（BSMV）的Type或ND18株系的RNA的小麦胚芽系统中合成的蛋白质，或来自Type或ND18感染的大麦的多核糖体合成的蛋白质，相互之间以及与来自Type和ND18感染植物的多肽进行了比较。在感染的大麦中诱导产生的表观分子量（Mr）为25、67和120×10³的多肽，可由感染植物的多核糖体或纯化的BSMV的RNA在体外合成。通过与纯化病毒粒子的衣壳蛋白进行共电泳、免疫沉淀以及未将[³⁵S]甲硫氨酸掺入该蛋白质，将25,000 Mr的多肽鉴定为BSMV衣壳蛋白。在含有Type或ND18 RNA的小麦胚芽和网织红细胞裂解液系统中合成的另外两种翻译产物中观察到了株系特异性差异。两种株系的RNA都指导合成71和82×10³ Mr的多肽。然而，ND18 RNA指导合成的71,000 Mr多肽量更大，而对于Type RNA，82,000 Mr多肽占主导。这两种蛋白质可能在体内进行了加工，因为在含有感染植物多核糖体的小麦胚芽提取物中这两种多肽的合成减少与67,000 Mr多肽的合成增加相关。在小麦胚芽系统中合成的几种额外多肽可能是过早终止产物，因为它们在网织红细胞裂解液中的合成大大减少。
