Octameric CENP-A Nucleosomes Are Present at Human Centromeres throughout the Cell Cycle

Octameric CENP-A Nucleosomes Are Present at Human Centromeres throughout the Cell Cycle

The presence of a single centromere on each chromosome that signals formation of a mitotic kinetochore is central to accurate chromosome segregation. The histone H3 variant centromere protein-A (CENP-A) is critical for centromere identity and function; CENP-A chromatin acts as an epigenetic mark to direct both centromere and kinetochore assembly. Interpreting the centromere epigenetic mark ensu...

Human centromeric CENP-A chromatin is a homotypic, octameric nucleosome at all cell cycle points

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 ...

HJURP Is a Cell-Cycle-Dependent Maintenance and Deposition Factor of CENP-A at Centromeres

The histone H3 variant CenH3, called CENP-A in humans, is central in centromeric chromatin to ensure proper chromosome segregation. In the absence of an underlying DNA sequence, it is still unclear how CENP-A deposition at centromeres is determined. Here, we purified non-nucleosomal CENP-A complexes to identify direct CENP-A partners involved in such a mechanism and identified HJURP. HJURP was ...

Response: Right-Handed Half-Nucleosomes at Centromeres

In conclusion, the composition of cen-tromeric particles—octameric, hexameric, tetrameric (tetrasomes or hemisomes), or a combination of these—as well as the mechanisms by which centromeric chro-matin acquires stable positive supercoil-ing certainly need further clarification. However, the results of Furuyama and Henikoff confirm that nucleosomes are not mere repetitive " canonical " chroma-tin...

Centromeric DNA destabilizes H3 nucleosomes to promote CENP-A deposition during the cell cycle