Federici B A, Vlak J M, Hamm J J
Department of Entomology, University of California, Riverside 92521.
J Gen Virol. 1990 Aug;71 ( Pt 8):1661-8. doi: 10.1099/0022-1317-71-8-1661.
The virions of three ascoviruses isolated from the noctuids Heliothis zea, Spodoptera frugiperda and Trichoplusia ni were compared with respect to their size and structure, protein composition and the size and relatedness of their DNAs. The virions of the isolates from H. zea (HAV) and T. ni (TAV) were allantoid in shape (400 x 130 nm), enveloped and contained an inner particle which appeared to have an internal lipid bilayer surrounding the DNA core. The virions of the S. frugiperda isolate (SAV) were similar in structure and size, but were bacilliform in shape, and after formation, were often occluded in vesiculate occlusion bodies. In preparations of purified virions of each isolate, at least 12 polypeptides were detected that ranged in size from 10K to 200K and contained a major species of about 50K. The genome of SAV was about 140 kbp in size, whereas those of TAV and HAV were approximately 180 kbp. Analysis of DNA fragment patterns of the three isolates generated with BamHI, HindIII or XhoI, as well as DNA-DNA dot blot and Southern blot hybridization studies, demonstrated that HAV and TAV were closely related but not identical. The DNA from SAV, however, did not hybridize with the DNA from either of the other isolates. Thus the ascovirus isolates from T. ni and H. zea are considered variants of the same virus, whereas the isolate from S. frugiperda is a separate member of the ascovirus group.
对从夜蛾科昆虫玉米螟、草地贪夜蛾和粉纹夜蛾中分离出的三种浓核病毒的病毒粒子，在大小和结构、蛋白质组成以及其DNA的大小和相关性方面进行了比较。从玉米螟（HAV）和粉纹夜蛾（TAV）分离出的病毒粒子呈腊肠形（400×130纳米），有包膜，并且含有一个内部粒子，该内部粒子似乎有一个围绕DNA核心的内部脂质双层。草地贪夜蛾分离株（SAV）的病毒粒子在结构和大小上相似，但呈杆状，形成后常被包裹在泡状包涵体内。在每个分离株的纯化病毒粒子制剂中，检测到至少12种多肽，其大小范围从10K到200K，并且含有一种约50K的主要种类。SAV的基因组大小约为140千碱基对，而TAV和HAV的基因组约为180千碱基对。用BamHI、HindIII或XhoI对这三种分离株产生的DNA片段模式进行分析，以及DNA-DNA斑点杂交和Southern杂交研究表明，HAV和TAV密切相关但并不相同。然而，SAV的DNA与其他任何一种分离株的DNA都不杂交。因此，从粉纹夜蛾和玉米螟分离出的浓核病毒被认为是同一病毒的变体，而从草地贪夜蛾分离出的病毒是浓核病毒组的一个独立成员。
