Iglewski W J
J Virol. 1971 Oct;8(4):446-54. doi: 10.1128/JVI.8.4.446-454.1971.
The distribution of labeled ribonucleic acid (RNA) associated with polysomes from Escherichia coli infected with the bacteriophage R17 was investigated. Pulse-labeling of RNA for 15 sec with (3)H-uridine resulted in increased labeling of the RNA associated with larger polysomes from infected cells as compared to control cells. Analysis of the RNA indicated that the increased labeling of large polysomes resulted from the presence of labeled double-stranded viral RNA. Other species of 15-sec pulse-labeled RNA entered into polysome formation in both infected and control cells. On the other hand, pulse-labeling of cultures for 15 sec with (3)H-uridine followed by a 5-min chase with unlabeled uridine resulted in a greater decrease in the amount of labeled RNA associated with large polysomes from infected cells as compared to control cells. This decreased labeling of large polysomes from infected cells was accompanied by an increased amount of label associated with the monomer to trimer regions. Analysis of RNA labeled under pulse-chase conditions indicated that virus infection resulted in an increased amount of heterogeneous 5 to 15S RNA in both the monomer to trimer and ribosomal subunit-soluble regions of the polysome profile. Labeled 5 to 15S RNA extracted directly from infected cells under pulse-chase conditions, without prior polysome fractionation, was characterized by a shift toward a distribution of smaller polynucleotides.
对感染噬菌体R17的大肠杆菌多核糖体相关标记核糖核酸（RNA）的分布进行了研究。用（3）H-尿苷对RNA进行15秒的脉冲标记，结果显示，与对照细胞相比，感染细胞中与较大多核糖体相关的RNA标记增加。对RNA的分析表明，大核糖体标记增加是由于存在标记的双链病毒RNA。在感染细胞和对照细胞中，其他15秒脉冲标记的RNA种类都参与了多核糖体的形成。另一方面，用（3）H-尿苷对培养物进行15秒脉冲标记，然后用未标记的尿苷进行5分钟追踪，结果显示，与对照细胞相比，感染细胞中与大多核糖体相关的标记RNA量减少得更多。感染细胞中大多核糖体标记的减少伴随着与单体到三聚体区域相关的标记量增加。对在脉冲追踪条件下标记的RNA的分析表明，病毒感染导致在多核糖体图谱的单体到三聚体区域以及核糖体亚基可溶区域中，5至15S异质RNA的量增加。在脉冲追踪条件下直接从感染细胞中提取的标记5至15S RNA，在未经多核糖体分级分离的情况下，其特征是向较小多核苷酸的分布转变。
