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bioRxiv · 10.1101/2024.07.25.605061

Co-recognition of histone acetylation and H3K4 trimethylation by GTE4-EML complex in Arabidopsis

Qian, F.·Zhao, Q.-Q.·Zhou, J.-X.·Yuan, D.-Y.·Su, Y.-N.·Li, L.·Chen, S.·He, X.-J.
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Abstract

Although histone acetylation and H3K4 trimethylation (H3K4me3) are well-known histone marks associated with active transcription, how they cooperate to regulate transcription remains largely unclear in plants. Our study revealed that the Bromodomain and Extra-terminal (BET) protein GTE4 binds to acetylated histone and forms a complex with the redundant H3K4me3-binding EMSY-Likeproteins EML1 or EML2 (EML1/2) in Arabidopsis thaliana. The eml1 eml2 (eml1/2) double mutant exhibited a morphological phenotype similar to the gte4 mutant, and most of the gte4-mediated differentially expressed genes were co-regulated in the eml1/2 mutant. Through chromatin immunoprecipitation followed by deep sequencing (ChIP-seq), we found that GTE4 and EML2 co-occupy protein-coding genes enriched with both histone acetylation and H3K4me3, exhibiting a synergistic effect on the association of the GTE4-EML complex with chromatin. The association of GTE4 with chromatin requires both the Bromodomain and the EML-interacting domain. This study identified a previously uncharacterized complex and uncovered how it cooperatively recognizes histone acetylation and H3K4me3 to facilitate gene transcription at the whole-genome level in Arabidopsis.

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Qian, F., Zhao, Q.-Q., Zhou, J.-X., Yuan, D.-Y., Su, Y.-N., Li, L., Chen, S., He, X.-J.. 2024-07-25. Co-recognition of histone acetylation and H3K4 trimethylation by GTE4-EML complex in Arabidopsis. https://doi.org/10.1101/2024.07.25.605061

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