Purification of a DNA supercoiling factor from the posterior silk gland of Bombyx mori.
收藏PubMed Central2026-05-16 收录
下载链接：
https://pmc.ncbi.nlm.nih.gov/articles/PMC54312/
下载链接
链接失效反馈官方服务：
资源简介：
A protein factor with an estimated molecular mass of 50 kDa has been purified to homogeneity from the silk gland of Bombyx mori. In the presence of a molar excess of this factor and eukaryotic DNA topoisomerase II, relaxed circular DNA is converted to the negatively supercoiled form. Eukaryotic DNA topoisomerase I cannot substitute for eukaryotic DNA topoisomerase II in the supercoiling reaction. The reaction is dependent on ATP and is inhibited by VP-16, a specific inhibitor of eukaryotic DNA topoisomerase II. When DNA topoisomerase I is subsequently added to the supercoiling reaction mixture, the supercoiled DNA becomes relaxed. These results suggest that when both the 50-kDa protein and eukaryotic DNA topoisomerase II are present in excess, unconstrained negative supercoils are introduced into DNA. IMAGES:
提供机构：
National Academy of Sciences
