Ndc10 is a platform for inner kinetochore assembly in budding yeast.
Publication Type:Journal Article
Source:Nat Struct Mol Biol, Volume 19, Issue 1, p.48-55 (2011)
Keywords:Amino Acid Sequence, Binding Sites, Crystallography, X-Ray, DNA, Fungal, DNA-Binding Proteins, Electrophoresis, Polyacrylamide Gel, Electrophoretic Mobility Shift Assay, Fungal Proteins, Kinetochores, Kluyveromyces, Models, Molecular, Molecular Sequence Data, Mutation, Protein Binding, Protein Multimerization, Protein Structure, Tertiary, Sequence Homology, Amino Acid
<p>Kinetochores link centromeric DNA to spindle microtubules and ensure faithful chromosome segregation during mitosis. In point-centromere yeasts, the CBF3 complex Skp1-Ctf13-(Cep3)(2)-(Ndc10)(2) recognizes a conserved centromeric DNA element through contacts made by Cep3 and Ndc10. We describe here the five-domain organization of Kluyveromyces lactis Ndc10 and the structure at 2.8 Å resolution of domains I-II (residues 1-402) bound to DNA. The structure resembles tyrosine DNA recombinases, although it lacks both endonuclease and ligase activities. Structural and biochemical data demonstrate that each subunit of the Ndc10 dimer binds a separate fragment of DNA, suggesting that Ndc10 stabilizes a DNA loop at the centromere. We describe in vitro association experiments showing that specific domains of Ndc10 interact with each of the known inner-kinetochore proteins or protein complexes in budding yeast. We propose that Ndc10 provides a central platform for inner-kinetochore assembly.</p>