Stender W
Nucleic Acids Res. 1980 Aug 11;8(15):3459-66. doi: 10.1093/nar/8.15.3459.
The interaction of sigma subunit of E. coli RNA polymerase with DNA, either double or single-stranded, and with two inhibitors of RNA synthesis was investigated by using antibodies directed against the subunit. Free sigma subunit was shown to interact with poly(dA), poly(dT), poly(dAC).poly(dGT), T7 DNA and, to a lesser degree, with lambda DNA. When the sigma subunit forms part of the holo enzyme, sigma also interacts with poly(dG).poly(dC). Rifampicin and streptolydigin interact with sigma in the holo enzyme and with free and core bound sigma subunit, respectively. The results suggest that sigma recognizes mainly AC-GT-sequences in double-stranded DNA. The findings are correlated with the base composition in RNA polymerase binding regions of promoters and suggest at least a general interaction between sigma subunit and single-stranded DNA in open complexes.
利用针对大肠杆菌RNA聚合酶σ亚基的抗体，研究了该亚基与双链或单链DNA以及两种RNA合成抑制剂之间的相互作用。结果表明，游离的σ亚基可与聚（dA）、聚（dT）、聚（dAC）·聚（dGT）、T7 DNA相互作用，与λ DNA的相互作用较弱。当σ亚基成为全酶的一部分时，σ也可与聚（dG）·聚（dC）相互作用。利福平与全酶中的σ相互作用，而链霉溶菌素分别与游离的和与核心结合的σ亚基相互作用。结果表明，σ主要识别双链DNA中的AC-GT序列。这些发现与启动子的RNA聚合酶结合区域中的碱基组成相关，并表明在开放复合物中，σ亚基与单链DNA之间至少存在普遍的相互作用。
