N-terminal acetylation of the Set1-COMPASS fine-tunes H3K4 methylation patterns (ChIPseq for shg1 and spp1 deletion strains)
H3K4 methylation is a conserved histone modification crucial for gene regulation, yet the post-translational modifications of the Set1-COMPASS complex remain largely unexplored. This study elucidates the significance of N-terminal acetylation in modulating H3K4 methylation patterns. Firstly, loss of NatA complex resulted in a significant decrease in H3K4me3 levels and a shift of H3K4me2 from 5' transcribed regions to promoters. Importantly, NatA physically interacted with the Set1-COMPASS complex and facilitated N-terminal acetylation of the Shg1 subunit. Surprisingly, deletion of SHG1 or mutation of the acetylation site (A2P) in Shg1 led to reduced H3K4 methylation in cells lacking Spp1. Additionally, NatB complex also contributed to H3K4 methylation regulation, potentially through N-terminal acetylation of Swd1. These findings highlight the novel role of N-terminal acetylation in fine-tuning the function of the Set1-COMPASS complex and shaping H3K4 methylation patterns. This study sheds light on the intricate regulation of H3K4 methylation and emphasizes the significance of N-terminal acetylation as a regulatory mechanism in this process. Overall design: Chromatin immunoprecipitation DNA sequencing (ChIP-seq) for histone modifications H3K4me2 and H3K4me3 as well as histone H3 in WT, shg1?, spp1? and shg1?spp1? strains in Saccharomyces cerevisiae.