Journal
BIOCHEMICAL JOURNAL
Volume 412, Issue -, Pages 425-433Publisher
PORTLAND PRESS LTD
DOI: 10.1042/BJ20071150
Keywords
DNA annealing; DNA unwinding; intramolecular regulation; RecQ helicase; zinc-finger motif
Categories
Ask authors/readers for more resources
RecQ family helicases, functioning as caretakers of genomic integrity, contain a zinc-binding motif which is highly conserved among these helicases, but does not have a substantial structural similarity with any other known zinc-finger folds. In the present study, we show that a truncated variant of the human RECQ5 beta helicase comprised of the conserved helicase domain only, a splice variant named RECQ5 alpha, possesses neither ATPase nor DNA-unwinding activities, but surprisingly displays a strong strand-annealing activity. In contrast, fragments of RECQ5 beta including the intact zinc-binding motif, which is located immediately downstream of the helicase domain, exhibit much reduced strand-annealing activity but are proficient in DNA unwinding. Quantitative measurements indicate that the regulatory role of the zinc-binding motif is achieved by enhancing the DNA-binding affinity of the enzyme. The novel intramolecular modulation of RECQ5 catalytic activity mediated by the zinc-binding motif may represent a universal regulation mode for all RecQ family helicases.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available