How a DNA Polymerase Clamp Loader Opens a Sliding Clamp
نویسندگان
چکیده
منابع مشابه
How a DNA polymerase clamp loader opens a sliding clamp.
Processive chromosomal replication relies on sliding DNA clamps, which are loaded onto DNA by pentameric clamp loader complexes belonging to the AAA+ family of adenosine triphosphatases (ATPases). We present structures for the ATP-bound state of the clamp loader complex from bacteriophage T4, bound to an open clamp and primer-template DNA. The clamp loader traps a spiral conformation of the ope...
متن کاملInterplay 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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The alternative proliferating-cell nuclear antigen (PCNA)-loader CTF18-RFC forms a stable complex with DNA polymerase ε (Polε). We observed that, under near-physiological conditions, CTF18-RFC alone loaded PCNA inefficiently, but loaded it efficiently when complexed with Polε. During efficient PCNA loading, CTF18-RFC and Polε assembled at a 3΄ primer-template junction cooperatively, and directe...
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The replication of a genome is a fundamental biological process that every organism must perform in order to transmit its genetic makeup to its progeny. We have been studying the molecular machines that are used to rapidly and accurately replicate the DNA genome of bacteria. In addition to the polymerase (the actual copying machine), organisms have a set of assemblies that enable the polymerase...
متن کاملThe sliding clamp of DNA polymerase III holoenzyme encircles DNA.
DNA polymerases that duplicate chromosomes are remarkably processive multiprotein machines. These replicative polymerases remain in continuous association with the DNA over tens to hundreds of kilobases. What is the chemical basis of their strong grip to the template? The mystery behind the high processivity of the replicative polymerase of the Escherichia coli chromosome, DNA polymerase III ho...
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ژورنال
عنوان ژورنال: Science
سال: 2011
ISSN: 0036-8075,1095-9203
DOI: 10.1126/science.1211884