Cse4 is part of an octameric nucleosome in budding yeast.
Mol Cell
; 35(6): 794-805, 2009 Sep 24.
Article
in En
| MEDLINE
| ID: mdl-19782029
ABSTRACT
The budding yeast CenH3 histone variant Cse4 localizes to centromeric nucleosomes and is required for kinetochore assembly and chromosome segregation. The exact composition of centromeric Cse4-containing nucleosomes is a subject of debate. Using unbiased biochemical, cell-biological, and genetic approaches, we have tested the composition of Cse4-containing nucleosomes. Using micrococcal nuclease-treated chromatin, we find that Cse4 is associated with the histones H2A, H2B, and H4, but not H3 or the nonhistone protein Scm3. Overexpression of Cse4 rescues the lethality of a scm3 deletion, indicating that Scm3 is not essential for the formation of functional centromeric chromatin. We also find that octameric Cse4 nucleosomes can be reconstituted in vitro. Furthermore, Cse4-Cse4 dimerization occurs in vivo at the centromeric nucleosome, and this requires the predicted Cse4-Cse4 dimerization interface. Taken together, our experimental evidence supports the model that the Cse4 nucleosome is an octamer, containing two copies each of Cse4, H2A, H2B, and H4.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Saccharomyces cerevisiae
/
Chromosomal Proteins, Non-Histone
/
Histones
/
Nucleosomes
/
Centromere
/
Saccharomyces cerevisiae Proteins
/
DNA-Binding Proteins
Type of study:
Prognostic_studies
Language:
En
Journal:
Mol Cell
Journal subject:
BIOLOGIA MOLECULAR
Year:
2009
Document type:
Article
Affiliation country:
Estados Unidos