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

• Published in: Genes & development Vol. 34; no. 3-4; pp. 226 - 238
• Main Authors: Singh, Puneet P, Shukla, Manu, White, Sharon A, Lafos, Marcel, Tong, Pin, Auchynnikava, Tatsiana, Spanos, Christos, Rappsilber, Juri, Pidoux, Alison L, Allshire, Robin C
• Format: Journal Article
• Language: English
• Published: United States Cold Spring Harbor Laboratory Press 01.02.2020
• Subjects: Chromatin - genetics; Chromatin - metabolism; Chromosomal Proteins, Non-Histone - metabolism; Chromosomes, Fungal - genetics; Chromosomes, Fungal - metabolism; DNA, Fungal - metabolism; Research Paper; Schizosaccharomyces - genetics; Schizosaccharomyces - metabolism; Schizosaccharomyces pombe Proteins - genetics; Schizosaccharomyces pombe Proteins - metabolism; Transcription Factors - metabolism; Transcription, Genetic - physiology; centromere; remodeling; chromosome segregation; transcription; epigenetic; kinetochore; fission yeast; histone; chromatin; CENP-A
• ISSN: 0890-9369; 1549-5477
• DOI: 10.1101/gad.332536.119

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 solubilized fission yeast CENP-A chromatin. All subunits of the Ino80 complex were enriched, including the auxiliary subunit Hap2. Chromatin association of Hap2 is Ies4-dependent. In addition to a role in maintenance of CENP-A chromatin integrity at endogenous centromeres, Hap2 is required for de novo assembly of CENP-A chromatin on naïve centromere DNA and promotes H3 turnover on centromere regions and other loci prone to CENP-A deposition. Prior to CENP-A chromatin assembly, Hap2 facilitates transcription from centromere DNA. These analyses suggest that Hap2-Ino80 destabilizes H3 nucleosomes on centromere DNA through transcription-coupled histone H3 turnover, driving the replacement of resident H3 nucleosomes with CENP-A nucleosomes. These inherent properties define centromere DNA by directing a program that mediates CENP-A assembly on appropriate sequences.