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This content will become publicly available on January 23, 2026

Title: High-resolution analysis of human centromeric chromatin
Centromeres are marked by the centromere-specific histone H3 variant CENP-A/CENH3. Throughout the cell cycle, the constitutive centromere-associated network is bound to CENP-A chromatin, but how this protein network modifies CENP-A nucleosome conformations in vivo is unknown. Here, we purify endogenous centromeric chromatin associated with the CENP-C complex across the cell cycle and analyze the structures by single-molecule imaging and biochemical assays. CENP-C complex–bound chromatin was refractory to MNase digestion. The CENP-C complex increased in height throughout the cell cycle culminating in mitosis, and the smaller CENP-C complex corresponds to the dimensions of in vitro reconstituted constitutive centromere-associated network. In addition, we found two distinct CENP-A nucleosomal configurations; the taller variant was associated with the CENP-C complex. Finally, CENP-A mutants partially corrected CENP-C overexpression–induced centromeric transcription and mitotic defects. In all, our data support a working model in which CENP-C is critical in regulating centromere homeostasis by supporting a unique higher order structure of centromeric chromatin and altering the accessibility of the centromeric chromatin fiber for transcriptional machinery.  more » « less
Award ID(s):
1911940
PAR ID:
10644502
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  
Publisher / Repository:
Life Science Alliance
Date Published:
Journal Name:
Life Science Alliance
Volume:
8
Issue:
4
ISSN:
2575-1077
Page Range / eLocation ID:
e202402819
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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