TY - JOUR
T1 - Cdc6-induced conformational changes in ORC bound to origin DNA revealed by cryo-electron microscopy
AU - Sun, Jingchuan
AU - Kawakami, Hironori
AU - Zech, Juergen
AU - Speck, Christian
AU - Stillman, Bruce
AU - Li, Huilin
N1 - Funding Information:
Chunyan Tang participated in the initial stage of the cryo-EM work. We thank Sylvain Mitelheiser for suggestions on the in vitro translation of ORC subunits and Patty Wendel for technical assistance in ORC preparation. This work was supported by National Institutes of Health grant nos. GM45436 (to B.S.) and GM74985 (to H.L.) and the United Kingdom Medical Research Council (to C.S.). H.K. was supported by Postdoctoral Fellowships for Research Abroad from the Japan Society for the Promotion of Science and the Uehara Memorial Foundation.
PY - 2012/3/7
Y1 - 2012/3/7
N2 - The eukaryotic origin recognition complex (ORC) interacts with and remodels origins of DNA replication prior to initiation in S phase. Here, we report a single-particle cryo-EM-derived structure of the supramolecular assembly comprising Saccharomyces cerevisiae ORC, the replication initiation factor Cdc6, and double-stranded ARS1 origin DNA in the presence of ATPγS. The six subunits of ORC are arranged as Orc1:Orc4:Orc5:Orc2:Orc3, with Orc6 binding to Orc2. Cdc6 binding changes the conformation of ORC, in particular reorienting the Orc1 N-terminal BAH domain. Segmentation of the 3D map of ORC-Cdc6 on DNA and docking with the crystal structure of the homologous archaeal Orc1/Cdc6 protein suggest an origin DNA binding model in which the DNA tracks along the interior surface of the crescent-like ORC. Thus, ORC bends and wraps the DNA. This model is consistent with the observation that binding of a single Cdc6 extends the ORC footprint on origin DNA from both ends.
AB - The eukaryotic origin recognition complex (ORC) interacts with and remodels origins of DNA replication prior to initiation in S phase. Here, we report a single-particle cryo-EM-derived structure of the supramolecular assembly comprising Saccharomyces cerevisiae ORC, the replication initiation factor Cdc6, and double-stranded ARS1 origin DNA in the presence of ATPγS. The six subunits of ORC are arranged as Orc1:Orc4:Orc5:Orc2:Orc3, with Orc6 binding to Orc2. Cdc6 binding changes the conformation of ORC, in particular reorienting the Orc1 N-terminal BAH domain. Segmentation of the 3D map of ORC-Cdc6 on DNA and docking with the crystal structure of the homologous archaeal Orc1/Cdc6 protein suggest an origin DNA binding model in which the DNA tracks along the interior surface of the crescent-like ORC. Thus, ORC bends and wraps the DNA. This model is consistent with the observation that binding of a single Cdc6 extends the ORC footprint on origin DNA from both ends.
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U2 - 10.1016/j.str.2012.01.011
DO - 10.1016/j.str.2012.01.011
M3 - Article
C2 - 22405012
AN - SCOPUS:84863296793
VL - 20
SP - 534
EP - 544
JO - Structure with Folding & design
JF - Structure with Folding & design
SN - 0969-2126
IS - 3
ER -