Intrinsic transcript cleavage activity of RNA polymerase.
نویسندگان
چکیده
The GreA and GreB transcript cleavage factors of Escherichia coli suppress elongation arrest and may have a proofreading role in transcription. With the use of E. coli greA-greB- mutant, RNA polymerase is demonstrated to possess substantial intrinsic transcript cleavage activity. Mildly alkaline pH mimics the effect of the Gre proteins by inducing transcript cleavage in ternary complexes and antagonizing elongation arrest through a cleavage-and-restart reaction. Thus, transcript cleavage constitutes the second enzymological activity of RNA polymerase along with polymerization/pyrophosphorolysis of RNA, whereas the Gre proteins merely enhance this intrinsic property.
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عنوان ژورنال:
- Proceedings of the National Academy of Sciences of the United States of America
دوره 92 10 شماره
صفحات -
تاریخ انتشار 1995