Correlation between the DNA supercoiling and the initiation of transcription by Escherichia coli RNA polymerase in vitro: role of the sequences upstream of the promoter region

FEBS Letters

Mishra, Rakesh K.¹  Chatterji, Dipankar¹  Gopal, Vijaya¹ 

[1] Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad-500 007, AP, India

关键词: T7 promoter;    RNA polymerase;    Supercoiling;    Abortive initiation;    Upstream sequence;    (E. coli);   

DOI  :  10.1016/0014-5793(90)80121-X

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Binding of Escherichia coli RNA polymerase and the abortive initiation of transcription at the A2 promoter ofbacteriophage T7, separately cloned in pBR322, was found to be strongly dependent on the degree of supercoiling of the plasmid. Supercoiling does not seem to play any role in the initiation of transcription at the T7A1 promoter under identical conditions. Plasmid containing T7A2 promoter was found to be less amenable to S1 nuclease in comparison to that having T7A1. Sequence comparison reveals a high G/C content upstream to the −35 region of T7A2 which by extra duplex stability probably renders the initiation of transcription more dependent on the state of supercoiling of the template.

【 授权许可】

Unknown