Structure of a central component of the yeast kinetochore: the Spc24p/Spc25p globular domain.
نویسندگان
چکیده
The Ndc80 complex, a kinetochore component conserved from yeast to humans, is essential for proper chromosome alignment and segregation during mitosis. It is an approximately 570 A long, rod-shaped assembly of four proteins--Ndc80p (Hec1), Nuf2p, Spc24p, and Spc25p--with globular regions at either end of a central shaft. The complex bridges from the centromere-proximal inner kinetochore layer at its Spc24/Spc25 globular end to the microtubule binding outer kinetochore layer at its Ndc80/Nuf2 globular end. We report the atomic structures of the Spc24/Spc25 globular domain, determined both by X-ray crystallography at 1.9 A resolution and by NMR. Spc24 and Spc25 fold tightly together into a single globular entity with pseudo-2-fold symmetry. Conserved residues line a common hydrophobic core and the bottom of a cleft, indicating that the functional orthologs from other eukaryotes will have the same structure and suggesting a docking site for components of the inner kinetochore.
منابع مشابه
Molecular organization of the Ndc80 complex, an essential kinetochore component.
The four-protein Ndc80 complex, an essential kinetochore component conserved from yeast to humans, plays an indispensable role in proper chromosome alignment and segregation during mitosis. In higher eukaryotes, the homologous complex probably resides in the middle domain of the trilaminar kinetochore, linking centromeric heterochromatin with microtubule-associated structures. We have prepared ...
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عنوان ژورنال:
- Structure
دوره 14 6 شماره
صفحات -
تاریخ انتشار 2006