9M4S

crystal structure of Arabidopsis thaliana ING2 PHD finger in complex with an H3K4me3 peptide

Summary for 9M4S

• Entry DOI: 10.2210/pdb9m4s/pdb
• Descriptor: PHD finger protein ING2, Histone H3.1, ZINC ION, ... (4 entities in total)
• Functional Keywords: histone modification, epigenetic regulation, h3k4me3, ing1, gene regulation
• Biological source: Arabidopsis thaliana (thale cress); More
• Total number of polymer chains: 2
• Total formula weight: 9911.93

Authors

Li, X.,Du, J. (deposition date: 2025-03-04, release date: 2025-11-05)

Primary citation

Luo, X.,Li, X.,Chen, Z.,Tian, S.,Liu, Y.,Shang, Z.,Chen, L.,Sun, Y.,Du, J.,He, Y.
A pair of readers of histone H3K4 methylation recruit Polycomb repressive complex 2 to regulate photoperiodic flowering.
Nat Commun, 16:9376-9376, 2025

PubMed Abstract: The transition from vegetative growth to reproduction in flowering plants is often timed by seasonal changes in day length (photoperiod). In the long-day (LD) plant Arabidopsis thaliana, the photoperiod pathway induces a daily rhythmic activation of the florigen gene FLOWERING LOCUS T (FT) to promote the floral transition. Under inductive LDs, FT expression is activated around dusk, but to be repressed overnight and into the early afternoon the next day. Here, we report that AtING1 and AtING2, Arabidopsis homologs of the mammalian Inhibitor of Growth (ING) proteins, read di- and tri-methylated histone-3 lysine 4 (H3K4me2/me3) on FT chromatin and further recruit Polycomb-repressive complex 2 (PRC2) to repress FT expression at night and into the early afternoon the next day, following FT activation at dusk. This prevents precocious flowering under inductive LDs. Our study reveals that the H3K4me2/me3-ING1/2-PRC2 module timely represses FT expression following the daily rhythmic FT activation, to prevent excessive FT expression and thus precisely control flowering time, in response to inductive photoperiodic signals.

PubMed: 41130979
DOI: 10.1038/s41467-025-64419-6

Experimental method

X-RAY DIFFRACTION (1.601 Å)