T7 RNA聚合酶对含有氧化性胸腺嘧啶损伤的短DNA模板体外转录的增强作用。

Enhancement of the in vitro transcription by T7 RNA polymerase of short DNA templates containing oxidative thymine lesions.

作者信息

Guerniou Valérie, Gasparutto Didier, Douki Thierry, Cadet Jean, Sauvaigo Sylvie

机构信息

Laboratoire Lésions des acides nucléiques, Service de chimie inorganique et biologique, FRE 2600, CEA/DSM/Département de recherche fondamentale sur la matière condensée, CEA-Grenoble, 17, rue des Martyrs, 38054 Grenoble cedex 9, France.

出版信息

C R Biol. 2005 Sep;328(9):794-801. doi: 10.1016/j.crvi.2005.07.003.

DOI:10.1016/j.crvi.2005.07.003

PMID:16168360

Abstract

5-(Hydroxymethyl)uracil, 5-formyluracil or 5-carboxyuracil can be formed in DNA upon exposure to ionizing radiations. We report the effect of the latter oxidative lesions on the in vitro transcription by T7 RNA polymerase using a single-stranded short model template. Kinetic experiments showed that the transcription yield was increased with the modified template. Due to the unforeseen presence of a hairpin structure within the transcribed RNA, we postulated that we are in the presence of a T7 RNA polymerase pausing signal and that the lesions within this critical DNA structure could interfere with normal regulation of RNA transcription.

摘要

暴露于电离辐射后，DNA中可形成5-（羟甲基）尿嘧啶、5-甲酰基尿嘧啶或5-羧基尿嘧啶。我们报告了使用单链短模型模板时，后一种氧化损伤对T7 RNA聚合酶体外转录的影响。动力学实验表明，转录产量随修饰模板而增加。由于转录的RNA中意外存在发夹结构，我们推测存在T7 RNA聚合酶暂停信号，并且这个关键DNA结构内的损伤可能干扰RNA转录的正常调控。