Abo1, a conserved bromodomain AAA-ATPase, maintains global nucleosome occupancy and organisation

作者:Gal Csenge; Murton Heather E; Subramanian Lakxmi; Whale Alex J; Moore Karen M; Paszkiewicz Konrad; Codlin Sandra; Baehler Juerg; Creamer Kevin M; Partridge Janet F; Allshire Robin C; Kent Nicholas A; Whitehall Simon K*
来源:EMBO Reports, 2016, 17(1): 79-93.
DOI:10.15252/embr.201540476

摘要

Maintenance of the correct level and organisation of nucleosomes is crucial for genome function. Here, we uncover a role for a conserved bromodomain AAA-ATPase, Abo1, in the maintenance of nucleosome architecture in fission yeast. Cells lacking abo1(+) experience both a reduction and mis-positioning of nucleosomes at transcribed sequences in addition to increased intragenic transcription, phenotypes that are hallmarks of defective chromatin re-establishment behind RNA polymerase II. Abo1 is recruited to gene sequences and associates with histone H3 and the histone chaperone FACT. Furthermore, the distribution of Abo1 on chromatin is disturbed by impaired FACT function. The role of Abo1 extends to some promoters and also to silent heterochromatin. Abo1 is recruited to pericentromeric heterochromatin independently of the HP1 ortholog, Swi6, where it enforces proper nucleosome occupancy. Consequently, loss of Abo1 alleviates silencing and causes elevated chromosome mis-segregation. We suggest that Abo1 provides a histone chaperone function that maintains nucleosome architecture genome-wide.

  • 出版日期2016-1