Auble D T, Allen T L, deHaseth P L
J Biol Chem. 1986 Aug 25;261(24):11202-6.
A family of variants of the PRM promoter of lambda phage was constructed, bearing nine base pair substitutions in a stretch of the spacer DNA separating the contacted -10 and -35 regions. The substituted sequences were chosen for their potential to adopt structures different from those of average B-form DNA and thus to affect the interaction of RNA polymerase with the two contacted regions. Characterization of the promoters in vitro and in vivo provides additional support for the lack of specific contacts in the substituted spacer region and shows that a small change in the relative rotational orientation of the -10 and -35 regions is inconsequential to promoter function. However, a 2-3-fold reduction in promoter activity is observed with promoters bearing substitutions of nonalternating dG-dC base pairs in either orientation. This corroborates other studies indicating the anomalous behavior of such sequences and suggests that the structure of the spacer DNA can modulate promoter recognition.
构建了λ噬菌体PRM启动子的一个变体家族，在分隔接触的-10和-35区域的一段间隔DNA中带有9个碱基对替换。选择这些替换序列是因为它们有可能形成不同于普通B型DNA的结构，从而影响RNA聚合酶与两个接触区域的相互作用。对这些启动子进行的体外和体内表征为替换间隔区域缺乏特异性接触提供了额外支持，并表明-10和-35区域相对旋转方向的微小变化对启动子功能无关紧要。然而，在任一方向上带有非交替dG-dC碱基对替换的启动子，其启动子活性会降低2至3倍。这证实了其他表明此类序列异常行为的研究，并表明间隔DNA的结构可以调节启动子识别。
