Golemboski D B, Lomonossoff G P, Zaitlin M
Department of Plant Pathology, Cornell University, Ithaca, NY 14853.
Proc Natl Acad Sci U S A. 1990 Aug;87(16):6311-5. doi: 10.1073/pnas.87.16.6311.
Nicotiana tabacum cv. Xanthi nn plants were transformed with nucleotides 3472-4916 of tobacco mosaic virus (TMV) strain U1. This sequence contains all but the three 3 terminal nucleotides of the TMV 54-kDa gene, which encodes a putative component of the replicase complex. These plants were resistant to infection when challenged with either TMV U1 virions or TMV U1 RNA at concentrations of up to 500 micrograms/ml or 300 micrograms/ml, respectively, the highest concentrations tested. Resistance was also exhibited when plants were inoculated at 100 micrograms/ml with the closely related TMV mutant YSI/1 but was not shown in plants challenged at the same concentrations with the more distantly related TMV strains U2 or L or cucumber mosaic virus. Although the copy number of the 54-kDa gene sequence varied in individual transformants from 1 to approximately 5, the level of resistance in plants was not dependent on the number of copies of the 54-kDa gene sequence integrated. The transformed plants accumulated a 54-kDa gene sequence-specific RNA transcript of the expected size, but no protein product was detected.
用烟草花叶病毒（TMV）U1株系的核苷酸3472 - 4916转化烟草品种黄花烟（Nicotiana tabacum cv. Xanthi nn）植株。该序列包含TMV 54 kDa基因除3'端三个核苷酸外的所有序列，54 kDa基因编码复制酶复合体的一个假定组分。当分别用浓度高达500微克/毫升的TMV U1病毒粒子或300微克/毫升的TMV U1 RNA（测试的最高浓度）进行挑战时，这些植株对感染具有抗性。当用100微克/毫升的密切相关TMV突变体YSI/1接种植株时也表现出抗性，但在用相同浓度的关系较远的TMV株系U2或L或黄瓜花叶病毒进行挑战的植株中未表现出抗性。尽管54 kDa基因序列的拷贝数在各个转化体中从1变化到约5，但植株中的抗性水平并不取决于整合的54 kDa基因序列的拷贝数。转化植株积累了预期大小的54 kDa基因序列特异性RNA转录本，但未检测到蛋白质产物。
