Head-to-tail polymerization by VEL proteins underpins cold-induced Polycomb silencing in flowering control

• DOI: 10.1016/j.celrep.2022.111607
• Publication Date: 2022-11-08T16:04:04Z
• Authors: Marc Fiedler; Elsa Franco-Echev...; Anna Schulten; Mathias Nielsen; Trevor J. Rutherford; Anna Yeates; Bilal Ahsan; Caroline Dean; Mariann Bienz
• Keywords: PRC2; Flowering Locus C; Polycomb-group proteins

Transcriptional silencing through the Polycomb machinery utilizes a "read-write" mechanism involving histone tail modifications. However, nucleation of and long-term stable transmission silenced state also requires P-olycomb Repressive Complex 2 (PRC2) accessory proteins, whose molecular role is poorly understood. The Arabidopsis VEL proteins are that interact with PRC2 to nucleate propagate at FLOWERING LOCUS C (FLC) locus, enabling early flowering in spring. Here, we report contain domain related an atypical four-helix bundle engages spontaneous concentration-dependent head-to-tail polymerization assemble dynamic biomolecular condensates. Mutations blocking this prevent FLC. Plant thus facilitate assembly multivalent complexes required for inheritance state.