Abstract:
:The RuvB protein is induced in Escherichia coli as part of the SOS response to DNA damage. It is required for genetic recombination and the postreplication repair of DNA. In vitro, the RuvB protein promotes the branch migration of Holliday junctions and has a DNA helicase activity in reactions that require ATP hydrolysis. We have used electron microscopy, image analysis, and three-dimensional reconstruction to show that the RuvB protein, in the presence of ATP, forms a dodecamer on double-stranded DNA in which two stacked hexameric rings encircle the DNA and are oriented in opposite directions with D6 symmetry. Although helicases are ubiquitous and essential for many aspects of DNA repair, replication, and transcription, three-dimensional reconstruction of a helicase has not yet been reported, to our knowledge. The structural arrangement that is seen may be common to other helicases, such as the simian virus 40 large tumor antigen.
journal_name
Proc Natl Acad Sci U S Aauthors
Stasiak A,Tsaneva IR,West SC,Benson CJ,Yu X,Egelman EHdoi
10.1073/pnas.91.16.7618subject
Has Abstractpub_date
1994-08-02 00:00:00pages
7618-22issue
16eissn
0027-8424issn
1091-6490journal_volume
91pub_type
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