The Prion-Like Properties of the INO80 Chromatin Remodeler Regulate Metabolic Gene Expression.

The INO80 chromatin-remodeling complex is a multi-subunit regulator of DNA-templated processes, yet the mechanisms that control remodeler function in vivo are not completely known. In this study, we report that the Ies6 subunit of the INO80 complex encodes a prion-like domain (PLD) within a larger region of predicted disorder. After transient inducible overexpression, both full-length Ies6 and the PLD domain alone aggregate in a manner that evades proteasome-mediated degradation, suggestive of prion-like behavior. Cytosolic aggregates are also visible with fluorescent microscopy following expression of the PLD alone. Loss of the protein chaperone Hsp70 increases Ies6 aggregation. In addition, deletion of ARP5, another INO80 subunit and binding partner of Ies6, also results in elevated protein aggregation. Finally, transcriptome analysis indicates that loss of PLD-mediated aggregation alters the expression of telomere-proximal and metabolic stress-responsive genes, including those involved in glucose starvation and respiratory programs, even under glucose-replete conditions. Together, these findings support a model in which Ies6 couples the INO80 complex to metabolic gene regulation via prion-like behavior, providing a potential new mechanism for tuning chromatin-based metabolic adaptation.