Johnson L D, Hadden J W
Nucleic Acids Res. 1977 Nov;4(11):4007-14. doi: 10.1093/nar/4.11.4007.
The effect of low concentrations of cyclic GMP (guanosine 3':5'-cyclic monophosphate) on the in vitro enzymatic activities of DNA-dependent RNA polymerases isolated from human peripheral blood lymphocytes has been investigated. In agreement with earlier studies which employed isolated nuclei as the enzyme source, an increase in the activity of partially purified RNA polymerase I is observed in the presence of cyclic GMP (10(-8) to 10(-10)M). RNA polymerase II activity is inhibited by the presence of cyclic GMP at concentrations between 10(-4) and 10(-10)M. RNA polymerase III activity is stimulated in a bimodal fashion by the presence of cyclic GMP with maximal activity noted at 10(-8) to 10(-10) M and 10(-5)M. In addition, [3H]cyclic GMP binds specifically to chromatographic fractions which are known to contain RNA polymerases I, II and III. This binding to RNA polymerases II and III is apprarently less tenacious as demonstrated by dissociation studies. The observations provide additional evidence for a role for cyclic GMP in the regulation of RNA synthesis.
研究了低浓度环鸟苷酸（鸟苷3':5'-环一磷酸）对从人外周血淋巴细胞中分离出的依赖DNA的RNA聚合酶体外酶活性的影响。与早期使用分离细胞核作为酶源的研究一致，在存在环鸟苷酸（10^(-8)至10^(-10)M）的情况下，观察到部分纯化的RNA聚合酶I的活性增加。在10^(-4)至10^(-10)M浓度之间的环鸟苷酸会抑制RNA聚合酶II的活性。环鸟苷酸以双峰方式刺激RNA聚合酶III的活性，在10^(-8)至10^(-10)M和10^(-5)M时活性最高。此外，[3H]环鸟苷酸特异性结合到已知含有RNA聚合酶I、II和III的色谱馏分上。解离研究表明，这种与RNA聚合酶II和III的结合显然不那么牢固。这些观察结果为环鸟苷酸在RNA合成调节中的作用提供了额外的证据。
