Phytochrome B triggers light-dependent chromatin remodelling through the PRC2-associated PHD finger protein VIL1

• Published in: Nature plants Vol. 7; no. 9; pp. 1213 - 1219
• Main Authors: Kim, Junghyun, Bordiya, Yogendra, Kathare, Praveen Kumar, Zhao, Bo, Zong, Wei, Huq, Enamul, Sung, Sibum
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01.09.2021; Nature Publishing Group
• Subjects: 631/449/1659; 631/449/2675; Acclimatization - genetics; Adaptation, Ocular - genetics; Arabidopsis - genetics; Biomedical and Life Sciences; Chromatin Assembly and Disassembly - genetics; Chromatin Assembly and Disassembly - physiology; Chromatin remodeling; Environmental conditions; Gene expression; Gene Expression Regulation, Plant; Gene loci; Gene silencing; Genes; Genes, Plant; Genetic Variation; Genotype; Histone H3; Histones; Homeodomain Proteins - genetics; Homeodomain Proteins - metabolism; Kinases; Letter; Life Sciences; Mutation; PHD Zinc Fingers - genetics; PHD Zinc Fingers - physiology; Phytochrome B; Phytochrome B - genetics; Phytochrome B - metabolism; Phytochromes; Plant Sciences; Polycomb group proteins; Polycomb-Group Proteins - genetics; Polycomb-Group Proteins - metabolism; Proteins; Stress, Physiological - genetics; Stress, Physiological - physiology; Temperature sensors; Vernalization
• ISSN: 2055-0278; 2055-0278
• DOI: 10.1038/s41477-021-00986-y

To compensate for a sessile nature, plants have developed sophisticated mechanisms to sense varying environmental conditions. Phytochromes (phys) are light and temperature sensors that regulate downstream genes to render plants responsive to environmental stimuli 1 – 4 . Here, we show that phyB directly triggers the formation of a repressive chromatin loop by physically interacting with VERNALIZATION INSENSITIVE 3-LIKE1/VERNALIZATION 5 (VIL1/VRN5), a component of Polycomb Repressive Complex 2 (PRC2) 5 , 6 , in a light-dependent manner. VIL1 and phyB cooperatively contribute to the repression of growth-promoting genes through the enrichment of Histone H3 Lys27 trimethylation (H3K27me3), a repressive histone modification. In addition, phyB and VIL1 mediate the formation of a chromatin loop to facilitate the repression of ATHB2 . Our findings show that phyB directly utilizes chromatin remodelling to regulate the expression of target genes in a light-dependent manner. Phytochrome B was found to directly trigger light-dependent chromatin remodelling by physically interacting with a component of PRC2, thereby regulating the expression of target genes, including growth-promoting genes.