2011N926

Seiji san:
1) Nature #7344
The title: Structure and mechanism of the chromatin remodelling factor ISW1a
They reported the crystal structures of S.cerevisiae ISW1a lacking its ATPase domain both alone and with DNA bound at resolutions of 3.25Å and 3.60Å, respectively. They also observed two different nucleosome-containning remodeling complexes by cryo-electron microscopy. The X-ray and electron microscopy structures combined with site-directed photocrosslinking analyses of these complexes suggest that ISW1a uses a dinucleosome substrate for chromatin remodelling.

2) Nature # 7364
Title: They generated synthetic CENP-A chromatin that recapitulates essential steps of centromere and kinetochore assembly in vitro.
The results showed that reconstituted CENP-A chromatin when added to cell-free extracts is sufficient for the assembly of centromere and kinetochore proteins, microtubule binding and stabilization, and mitotic checkpoint function. They also showed that the conserved carboxy terminus of CENP-A is necessary and sufficient for centromere and kinetochore protein recruitment and function but that the CENP-A targeting domain-required for new CENP-A histone assembly2-is not.

Zhu san:
PNAS: Vol 108
Title: Histone fold modifications control nucleosome unwarpping and disassembly
Here, they demonstrated that histone PTMs within distinct structured regions of the nucleosome directly regulate the inherent dynamic properties of the nucleosome and single molecule magnetic tweezers measurements determined that only PTMs near the nucleosome dyad increase the rate of histone release in unwrapped nucleosomes. These studies are consistent with the conclusion that histone PTMs may independently influence nucleosome dynamics and associated chromatin functions.

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