Clamp loader structure predicts the architecture of DNA polymerase III holoenzyme and RFC
نویسندگان
چکیده
Recent determinations of the crystal structure of the Escherichia coli gamma complex and delta-beta assembly have shed light on the bacterial clamp loading reaction. In this review, we discuss the structures of delta-beta and the gamma(3)deltadelta' complex and its mechanism of action as a clamp loader of the E. coli beta sliding clamp. We also expand upon the implications of the structural findings to the structure and function of the eukaryotic clamp loader, RFC, and the structure of E. coli DNA polymerase III holoenzyme.
منابع مشابه
Interplay of clamp loader subunits in opening the beta sliding clamp of Escherichia coli DNA polymerase III holoenzyme.
The Escherichia coli beta dimer is a ring-shaped protein that encircles DNA and acts as a sliding clamp to tether the replicase, DNA polymerase III holoenzyme, to DNA. The gamma complex (gammadeltadelta'chipsi) clamp loader couples ATP to the opening and closing of beta in assembly of the ring onto DNA. These proteins are functionally and structurally conserved in all cells. The eukaryotic equi...
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ورودعنوان ژورنال:
- Current Biology
دوره 11 شماره
صفحات -
تاریخ انتشار 2001