7O6U

Crystal structure of the VIN3 VEL polymerising domain (R554A R556D mutant)

Summary for 7O6U

• Entry DOI: 10.2210/pdb7o6u/pdb
• Descriptor: Protein VERNALIZATION INSENSITIVE 3 (2 entities in total)
• Functional Keywords: protein oligomerization, head-to-tail polymerization, domain swapping, nuclear protein
• Biological source: Arabidopsis thaliana (Mouse-ear cress)
• Total number of polymer chains: 1
• Total formula weight: 8174.07

Authors

Fiedler, M.,Franco-Echevarria, E.,Dean, C.,Bienz, M. (deposition date: 2021-04-12, release date: 2022-11-09, Last modification date: 2024-11-06)

Primary citation

Fiedler, M.,Franco-Echevarria, E.,Schulten, A.,Nielsen, M.,Rutherford, T.J.,Yeates, A.,Ahsan, B.,Dean, C.,Bienz, M.
Head-to-tail polymerization by VEL proteins underpins cold-induced Polycomb silencing in flowering control.
Cell Rep, 41:111607-111607, 2022

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

PubMed: 36351412
DOI: 10.1016/j.celrep.2022.111607

Experimental method

X-RAY DIFFRACTION (1.84 Å)