Studies on Viral Interaction in Plant Cells.

对大麦和烟草中病毒的相互作用进行了研究，重点研究了病毒的互补增殖。烟草花叶病毒(TMV)在大麦细胞中不繁殖，但在接种大麦条纹花叶病毒(BSMV)后大量繁殖。TMV在最上部的叶片中含量最高，说明BSMV有助于TMV在植株体内的转运。然而，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增殖，说明BSMV首先补充了TMV的增殖，从而促进了TMV的转位。其他病毒如CGMMV、CyMV、CMV即使接种BSMV也不能在大麦细胞中繁殖。另一方面，烟草花叶病毒不能在烟草叶片和愈伤组织细胞中增殖。因此，BSMV的辅助功能是一种特定的、单向的功能。将TMV或TMV-RNA与RNA1、2或3或BSMV共接种，结果表明BSMV的辅助功能是在RNA2上编码的。通过电泳法分离侵染特异性蛋白，并与TMV或TMV-RNA共接种，以确定大麦愈伤组织细胞和原生质体中TMV增殖的蛋白。然而，在共同接种的细胞中没有观察到TMV增殖的迹象，这表明BSMV RNA2上可能编码的蛋白没有被分离出来。分离出具有BSMV复制酶活性的蛋白质组分，但还没有纯化到可以在显著水平上检测TMV-RNA模板活性的程度。TMV在大麦细胞中互补增殖的复制酶的纯化和蛋白质的分离正在进行中。初步数据表明，大麦细胞中似乎存在抑制抗性机制调控表达的蛋白质。

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.