INCREASED DNA METHYLATION 3 forms a potential chromatin remodelling complex with HAIRPLUS to regulate DNA methylation and trichome development in tomato

作者：Tünde Nyikó, Péter Gyula, Szilvia Ráth, Anita Sós‐Hegedűs, Tibor Csorba, Syed Hussam Abbas, Károly Bóka, Aladár Pettkó‐Szandtner, Ágnes M. Móricz, Béla Péter Molnár, Anna Laura Erdei, György Szittya · 发表于：The Plant Journal · 年份：2025 · DOI：10.1111/tpj.70085 · 被引用次数：5 · 研究领域：Plant Molecular Biology Research、Plant Gene Expression Analysis、Plant Reproductive Biology

DNA methylation, a dynamic epigenetic mark influencing gene expression, is regulated by DNA demethylases that remove methylated cytosines at genomic regions marked by the INCREASED DNA METHYLATION (IDM) complex. In Arabidopsis, IDM3, a small α-crystalline domain-containing protein, stabilises the IDM complex. To investigate its role in tomato, we generated slidm3 mutants using genome editing. These mutants displayed a 'hairy' phenotype with increased glandular trichomes, resembling the hairplus (hap) mutant. Affinity purification of SlIDM3-GFP associated proteins identified several chromatin remodelling factors, including HAP. Genome-wide DNA methylation analysis revealed sequence context dependent alterations in the slidm3-1 plants, similar to the hap mutant. CHH methylation was predominantly increased, while CG methylation, particularly in intergenic regions, was decreased in both mutants. This imbalanced methylation suggests the presence of a 'methylstat' mechanism attempting to restore methylation levels at abnormally demethylated sites in the mutants. Comparative functional analysis of differentially methylated regions in the slidm3-1 and hap mutants identified potential methylation-regulated genes that could be linked to the hairy phenotype. Our findings indicate that SlIDM3 may form a chromatin remodelling complex with HAP, epigenetically regulating trichome development.