The trxG protein ULT1 regulates Arabidopsis organ size by interacting with TCP14/15 to antagonize the LIM peptidase DA1 for H3K4me3 on target genes

• DOI: 10.1016/j.xplc.2024.100819
• Publication Date: 2024-01-12T16:16:54Z
• Authors: Fan Xu; Huixue Dong; Weijun Guo; Liang Le; Yexing Jing; Jennifer C. Fletcher; Jiaqiang Sun; Li Pu
• Keywords: H3K4me3

Plant organ size is an important agronomic trait that greatly determines plant yield. However, despite its central importance, the genetic and molecular mechanisms underlying control remain elusive. Here, we report trithorax group protein ULTRAPETALA1 (ULT1) interacts with TCP14/15 transcription factors (TFs) by antagonizing LIM-peptidase DA1 to regulate in Arabidopsis. Loss of ULT1 function significantly increases rosette leaf, petal, silique seed size, while overexpression results reduced size. associates TCP14 TCP15 co-regulate cell affecting cellular endoreduplication. Transcriptome analysis reveals common target genes involved endoreduplication leaf development. can be recruited promote H3K4 trimethylation (H3K4me3) at genes, thereby activating their expression determine final sizes. Furthermore, found influences interaction antagonizes effect DA1's degradation on TCP14/TCP15. Collectively, our findings uncover a novel epigenetic mechanism regulation