Studies on Viral Interaction in Plant Cells.

研究了大麦和烟草植物中病毒的相互作用，重点是病毒的互补增殖。烟草花叶病毒（TMV）在大麦细胞中不增殖，但在接种大麦条纹花叶病毒（BSMV）后，TMV大量增殖。TMV在植株上部叶片中的数量最多，说明BSMV有助于TMV在接种植株上的转移。而用聚乙二醇法或显微注射法共接种BSMV时，TMV在大麦叶片原生质体中大量繁殖，说明BSMV首先补充TMV的增殖，从而帮助TMV的易位。其它病毒如CGMMV、CyMV、CMV等即使接种BSMV也不能在大麦细胞中增殖。另一方面，BSMV在烟草叶片或愈伤组织细胞中不增殖。因此，BSMV的辅助功能是特异的和单向的。将TMV或TMV-RNA与RNA 1、RNA 2、RNA 3或BSMV共接种，表明BSMV的辅助功能是由RNA 2编码的。通过电泳分离感染特异性蛋白，并与TMV或TMV-RNA共接种，以指定负责大麦愈伤组织细胞和原生质体中tmv增殖的蛋白。然而，在共接种的细胞中没有观察到TMV增殖的迹象，表明尚未分离出BSMV RNA 2上编码的推定蛋白。分离具有BSMV复制酶活性的蛋白质级分，但尚未纯化到可以在显著水平上测试TMV-RNA的模板活性的程度。复制酶的纯化和分离的蛋白质负责在大麦细胞中的TMV的互补增殖正在进行中。实验数据表明，有蛋白质似乎抑制大麦细胞中抗性机制的调控表达。

Viral interactions in barley and tobacco plants were studied with an emphasis on complementative multiplication of viruses. Tobacco mosaic virus (TMV) did not multiply in barley cells, but multiplied to a significant quantity provided it was inoculated with barley stripe mosaic virus(BSMV). Quantity of TMV was highest in the uppermost leaves suggesting that BSMV helped TMV to translocate the inoculated plants. TMV, however, multiplied in barley leaf protoplasts when co-inoculated with BSMV by polyethylene glycol mtehod or microinjection indicating that BSMV complemented the multiplication of TMV first and consequently helped its translocation. Other viruses such as CGMMV, CyMV, CMV did not multiply in barley cells even if they were inoculated with BSMV. On the other hand, BSMV did not multiply in tobacco leaf or callus cells in the presence of TMV. Thus the helper function of BSMV is a specific and unidirectional one. Co-inoculation of TMV or TMV-RNA with either RNA 1,2,or 3 or BSMV revealed that the helper function of BSMV was coded on RNA 2. Infection specific proteins were isolated by electrophoresis and co-inoculated with TMV or TMV-RNA to specify the protein that is responsible for tmv multiplication in barley callus cells and protoplasts. However, no signs of TMV multiplication were observed in the co-inoculated cells indicating that the putative protein encoded on BSMV RNA 2 had not been isolated. Protein fraction with replicase activity of BSMV was isolated, but has not been purified to the extent that template activity of TMV-RNA could be tested at a significant level. Purification of replicase and isolation of the protein responsible for the complementative multiplication of TMV in barley cells are in progress. Prelimonary data indicate that there are proteins that seem to suppress the regulatory expression of resistance mechanisms in barley cells.