This Article Free via Open Access: OA OA Abstract OA Full Text Full Text (PDF) Supporting Information Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a colleague Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Add to My File Cabinet Download to citation manager Request Copyright Permission Citing Articles Citing Articles via HighWire Citing Articles via CrossRef Citing Articles via ISI Web of Science (3) Citing Articles via Google Scholar Google Scholar Articles by Leschziner, A. E. Articles by Nogales, E. Search for Related Content PubMed PubMed Citation Articles by Leschziner, A. E. Articles by Nogales, E. Social Bookmarking                What's this?

 Previous Article  | Table of Contents |  Next Article 

Conformational flexibility in the chromatin remodeler RSC observed by electron microscopy and the orthogonal tilt reconstruction method

Andres E. Leschziner^*,, Anjanabha Saha^,, Jacqueline Wittmeyer, Yongli Zhang^¶, Carlos Bustamante^*,,¶,||,**,, Bradley R. Cairns^,,, and Eva Nogales^*,,¶,

Departments of *Molecular and Cell Biology, ^||Chemistry, and **Physics, and Howard Hughes Medical Institute, University of California, Berkeley, CA 94720; Department of Oncological Sciences, Huntsman Cancer Institute, and Howard Hughes Medical Institute, University of Utah School of Medicine, Salt Lake City, UT 84112; and ^¶Lawrence Berkeley National Laboratory, Berkeley, CA 94720

View larger version (70K): [in this window] [in a new window]   Fig. 1. Analysis of RSC's amenability to the orthogonal tilt reconstruction method. Comparison of class averages obtained through reference-free alignment and classification of images collected at either 0° (horizontal rhomboid) or ±45° tilt (tilted rhomboid) showing the presence of similar characteristic views in both samples.

View larger version (53K): [in this window] [in a new window]   Fig. 2. RSC conformational variability. (A) Reconstructions of two conformers of RSC. The initial models were obtained by using the Orthogonal Tilt Reconstruction method and then refined by projection-matching against 0° data. The names of the main features of the reconstructions are indicated in italics. The "open" and "closed" conformations differ mainly in the position of the arm (at the right of the structures shown in the top row). The bottom row shows the "top" and "back" views of the open conformer. A scale bar corresponding to 100 Å is shown. (B) Comparison of reprojections ("Prj") of the structures shown in A with the best-matching reference-free class averages ("Avg"). (C) Four selected experimental class averages for RSC showing a variety of positions occupied by the arm (arrows).

View larger version (39K): [in this window] [in a new window]   Fig. 3. Fitting of a nucleosome into the open and closed conformations of RSC. The crystal structure of the nucleosome (23) (PDB ID code 1AOI) was filtered to the resolution of the two reconstructions (37 Å) and manually fitted into each of the two reconstructed conformations. The filtered nucleosome is shown in yellow, and the RSC reconstructions are shown in gray.

View larger version (42K): [in this window] [in a new window]   Fig. 4. Model of nucleosome binding by RSC. The x-ray crystal structure of the nucleosome (23) (PDB ID code 1AOI) was manually fitted into the central cavity of RSC. The nucleosome is shown as a ribbon diagram within a translucent surface representation filtered to 10 Å. The DNA is represented in gold, and the protein is represented in orange. Back (Left) and front (Right) views of the complex are shown. The entry/exit points of the nucleosomal DNA are indicated with green arrows, the dyad axis (blue cylinder) is indicated with a blue arrow, the histone H3 tail visible in the crystal structure is indicated with an orange arrow, and the binding site for the translocase domain is shown on the DNA with maroon arrows.

CiteULike

Complore

Connotea

Del.icio.us

Digg