巨型DNA分子通过构象转变表现出转录活性的开/关切换。

Giant DNA molecules exhibit on/off switching of transcriptional activity through conformational transition.

作者信息

Tsumoto Kanta, Luckel François, Yoshikawa Kenichi

机构信息

Department of Chemistry for Materials, Faculty of Engineering, Mie University, Tsu, Mie 514-8507, Japan.

出版信息

Biophys Chem. 2003 Oct 1;106(1):23-9. doi: 10.1016/s0301-4622(03)00138-8.

DOI:10.1016/s0301-4622(03)00138-8

PMID:14516909

Abstract

We found that the transcriptional activity of large DNAs (40 kbp) can be completely inhibited by adding condensing agents, spermine and poly(ethylene glycol), whereas under the same conditions short fragments (140 bp) still show active transcription. Fluorescence microscopic observations of large DNAs revealed clear correlation between the higher-order structure of templates and their transcriptional activity. The steep decrease in transcriptional activity leading to complete inhibition, or on/off switching, is interpreted in terms of conformational transition of the ensemble of DNA molecules.

摘要

我们发现，通过添加凝聚剂、精胺和聚乙二醇，可以完全抑制大型DNA（40千碱基对）的转录活性，而在相同条件下，短片段（140碱基对）仍显示出活跃的转录。对大型DNA的荧光显微镜观察揭示了模板的高阶结构与其转录活性之间的明显相关性。转录活性急剧下降导致完全抑制或开/关切换，这可以根据DNA分子整体的构象转变来解释。