Phase separation directs ubiquitination of gene-body nucleosomes.

ABSTRACT: The conserved yeast E3 ubiquitin ligase Bre1 and its partner, the E2 ubiquitin-conjugating enzyme Rad6, monoubiquitinate histone H2B across gene bodies during the transcription cycle¹. Although processive ubiquitination might-in principle-arise from Bre1 and Rad6 travelling with RNA polymerase II², the mechanism of H2B ubiquitination across genic nucleosomes remains unclear. Here we implicate liquid-liquid phase separation³ as the underlying mechanism. Biochemical reconstitution shows that Bre1 binds the scaffold protein Lge1, which possesses an intrinsically disordered region that phase-separates via multivalent interactions. The resulting condensates comprise a core of Lge1 encapsulated by an outer catalytic shell of Bre1. This layered liquid recruits Rad

SUBMITTER: Gallego LD 

PROVIDER: S-EPMC7481934 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature