Human centromeric CENP-A chromatin is a homotypic, octameric nucleosome at all cell cycle points
| Autor: | Don W. Cleveland, Dong Hyun Kim, Bing Ren, Ah Young Lee, Daniele Fachinetti, Kristen Nguyen, Adeline K. Wong, Cees Dekker, Yael Nechemia-Arbely, Ben E. Black, Nikolina Sekulic, Karen H. Miga, Gautam V. Soni |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
0301 basic medicine
Chromosomal Proteins Non-Histone Centromere macromolecular substances DNA Satellite Medical and Health Sciences Autoantigens Article Cell Line Histones 03 medical and health sciences Histone H3 0302 clinical medicine Centromere Protein A Cell Line Tumor Histone methylation Nucleosome Histone code Humans Research Articles Tumor biology Cell Cycle Chromosome Cell Biology Non-Histone DNA Biological Sciences Molecular biology Chromatin Cell biology Nucleosomes Chromosomal Proteins 030104 developmental biology Histone Satellite Hela Cells biology.protein 030217 neurology & neurosurgery Developmental Biology HeLa Cells |
| Zdroj: | The Journal of Cell Biology The Journal of cell biology, vol 216, iss 3 The Journal of Cell Biology, 216(3) |
| ISSN: | 0021-9525 |
| DOI: | 10.1083/jcb.201608083 |
| Popis: | In this study, the authors use new reference models for 23 human centromeres and find that at all cell cycle phases centromeric CENP-A chromatin complexes are octameric nucleosomes with two molecules of CENP-A. This finding refutes previous models that have suggested that hemisomes may briefly transition to octameric nucleosomes. Chromatin assembled with centromere protein A (CENP-A) is the epigenetic mark of centromere identity. Using new reference models, we now identify sites of CENP-A and histone H3.1 binding within the megabase, α-satellite repeat–containing centromeres of 23 human chromosomes. The overwhelming majority (97%) of α-satellite DNA is found to be assembled with histone H3.1–containing nucleosomes with wrapped DNA termini. In both G1 and G2 cell cycle phases, the 2–4% of α-satellite assembled with CENP-A protects DNA lengths centered on 133 bp, consistent with octameric nucleosomes with DNA unwrapping at entry and exit. CENP-A chromatin is shown to contain equimolar amounts of CENP-A and histones H2A, H2B, and H4, with no H3. Solid-state nanopore analyses show it to be nucleosomal in size. Thus, in contrast to models for hemisomes that briefly transition to octameric nucleosomes at specific cell cycle points or heterotypic nucleosomes containing both CENP-A and histone H3, human CENP-A chromatin complexes are octameric nucleosomes with two molecules of CENP-A at all cell cycle phases. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|