used during segmentation. Subdomains were grouped into putative subunits
based on molecular shape and subunit localization information.
The cryo-EM 3D density map of ScORC-Cdc6-DNA has been deposited in the
Electron Microscopy Data Bank under accession number 5381.
Supplemental Information includes four ﬁgures and one movie and can be
found with this article online at doi:10.1016/j.str.2012.01.011.
Chunyan Tang participat ed 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
Received: November 1, 2011
Revised: January 16, 2012
Accepted: January 17, 2012
Published: March 6, 2012
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Cryo-EM of ORC-Cdc6 Bound to DNA
Structure 20, 534–544, March 7, 2012 ª2012 Elsevier Ltd All rights reserved 543