Scm3 deposits a (Cse4-H4)2 tetramer onto DNA through a Cse4-H4 dimer intermediate.

ABSTRACT: The assembly of centromeric nucleosomes is mediated by histone variant-specific chaperones. In budding yeast, the centromere-specific histone H3 variant is Cse4, and the histone chaperone Scm3 functions as a Cse4-specific nucleosome assembly factor. Here, we show that Scm3 exhibits specificity for Cse4-H4, but also interacts with major-type H3-H4 and H2A-H2B. Previously published structures of the Scm3 histone complex demonstrate that Scm3 binds only one copy of Cse4-H4. Consistent with this, we show that Scm3 deposits Cse4-H4 through a dimer intermediate onto deoxyribonucleic acid (DNA) to form a (Cse4-H4)2-DNA complex (tetrasome). Scm3-bound Cse4-H4 does not form a tetramer in the absence of DNA. Moreover, we demonstrate that Cse4 and H3 are structurally compatible to be incorporated in

SUBMITTER: Dechassa ML 

PROVIDER: S-EPMC4027189 | biostudies-literature | 2014 May

REPOSITORIES: biostudies-literature