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Updated: May 25, 2026
In Vitro Characterization of Histone Chaperones using Analytical, Pull-Down and Chaperoning Assays
Published on: December 29, 2021
Histone density is maintained during transcription mediated by the chromatin remodeler RSC and histone chaperone NAP1
Benjamin G Kuryan1, Jessica Kim, Nancy Nga H Tran
1David Geffen School of Medicine, Department of Biological Chemistry, 615 Charles E. Young Drive, University of California, Los Angeles, CA 90095-1737, USA.
Abstract:
ATPases and histone chaperones facilitate RNA polymerase II (pol II) elongation on chromatin. In vivo, the coordinated action of these enzymes is necessary to permit pol II passage through a nucleosome while restoring histone density afterward. We have developed a biochemical system recapitulating this basic process. Transcription through a nucleosome in vitro requires the ATPase remodels structure of chromatin (RSC) and the histone chaperone nucleosome assembly protein 1 (NAP1). In the presence of NAP1, RSC generates a hexasome. Despite the propensity of RSC to evict histones, NAP1 reprograms the reaction such that the hexasome is retained on the template during multiple rounds of transcription. This work has implications toward understanding the mechanism of pol II elongation on chromatin.
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