Dishler A V, Pumpen P P, Gren E Ia
Genetika. 1980;16(10):1719-28.
A number of ts-mutants with altered characteristics of RNA synthesis in non-suppressor cells at elevated temperatures have been obtained after HNO2-treatment of phage MS2am623 (amber mutation in site 50). The mutant ts130 is studied in detail: its peak of RNA synthesis is displaced 10 min. later and the total amount of RNA is reduced in 5-10 times. No RNA synthesis is observed in ts130-infected cell at 46 degrees C. Changes in the character of RNA synthesis are accompanied by the over-production of phage subunit of replicase: at 42 degrees C the replicase/RNA ratio in ts130 is 20 times higher than that of the original phage MS2am623. It is assumed that there is a decrease in the activity of replicase--RNA repressor complex in ts130 resulting in the loss of replicase control over its own synthesis while the control of coat protein synthesis remains unaffected.
在用亚硝酸处理噬菌体MS2am623（第50位点的琥珀突变）后，获得了一些在高温下非抑制细胞中RNA合成特性发生改变的温度敏感突变体。对突变体ts130进行了详细研究：其RNA合成峰值延迟10分钟出现，RNA总量减少了5至10倍。在46℃时，ts130感染的细胞中未观察到RNA合成。RNA合成特性的变化伴随着复制酶噬菌体亚基的过量产生：在42℃时，ts130中的复制酶/RNA比率比原始噬菌体MS2am623高20倍。据推测，ts130中复制酶-RNA阻遏物复合物的活性降低，导致复制酶对自身合成的控制丧失，而外壳蛋白合成的控制仍未受影响。
