Author:
Bartsch I,Schoneberg C,Grummt I
Abstract
Termination of rRNA gene transcription is dependent on an 18-base-pair sequence motif, AGGTCGAC CAG AT TA NTCCG (the Sal box), which is present several times in the spacer region downstream of the 3' end of the pre-rRNA coding region. We report here the purification to molecular homogeneity of a nuclear factor which specifically interacts with the Sal box element. Addition of the isolated protein to S-100 extracts which contain low levels of the Sal box-binding protein and are therefore termination incompetent restores terminating activity, indicating that this protein is a polymerase I-specific transcription termination factor. The purified protein (termed TTFI) has a molecular weight of approximately 105,000 on sodium dodecyl sulfate-polyacrylamide gels. Mild proteolysis generates a relatively protease-resistant core which still specifically recognizes its target sequence. However, the termination activity has been lost, suggesting that the interaction with the DNA and the interaction with the transcription apparatus reside in different protein domains.
Publisher
American Society for Microbiology
Subject
Cell Biology,Molecular Biology
Cited by
68 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献