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bioRxiv · 10.1101/778639

Hap2-Ino80 facilitated transcription promotes de novo establishment of CENP-A chromatin

Singh, P. P.·Shukla, M.·White, S. A.·Tong, P.·Auchynnikava, T.·Spanos, C.·Rappsilber, J.·Pidoux, A. L.·Allshire, R. C.
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Abstract

Centromeres are maintained epigenetically by the presence of CENP-A, an evolutionarily-conserved histone H3 variant, which directs kinetochore assembly and hence, centromere function. To identify factors that promote assembly of CENP-A chromatin, we affinity selected solubilised fission yeast CENP-ACnp1 chromatin. All subunits of the Ino80 complex were enriched, including the auxiliary subunit Hap2. In addition to a role in maintenance of CENP-ACnp1 chromatin integrity at endogenous centromeres, Hap2 is required for de novo assembly of CENP-ACnp1 chromatin on naive centromere DNA and promotes H3 turnover on centromere regions and other loci prone to CENP-ACnp1 deposition. Prior to CENP-ACnp1 chromatin assembly, Hap2 facilitates transcription from centromere DNA. These analyses suggest that Hap2-Ino80 destabilises H3 nucleosomes on centromere DNA through transcription-coupled histone H3 turnover, driving the replacement of resident H3 nucleosomes with CENP-ACnp1 nucleosomes. These inherent properties define centromere DNA by directing a program that mediates CENP-ACnp1 assembly on appropriate sequences.

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Singh, P. P., Shukla, M., White, S. A., Tong, P., Auchynnikava, T., Spanos, C., Rappsilber, J., Pidoux, A. L., Allshire, R. C.. 2019-09-23. Hap2-Ino80 facilitated transcription promotes de novo establishment of CENP-A chromatin. https://doi.org/10.1101/778639

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