The engagement of histone lysine methyltransferases with nucleosomes: structural basis, regulatory mechanisms, and therapeutic implications

Histone lysine methyltransferases (HKMTs) deposit methyl groups onto lysine residues on histones and play important roles in regulating chromatin structure and gene expression. The structures and functions of HKMTs have been extensively investigated in recent decades, significantly advancing our understanding of the dynamic regulation of histone methylation. Here, we review the recent progress in structural studies of representative HKMTs in complex with nucleosomes (H3K4, H3K27, H3K36, H3K79, and H4K20 methyltransferases), with emphasis on the molecular mechanisms of nucleosome recognition and trans-histone crosstalk by these HKMTs. These structural studies inform HKMTs' roles in tumorigenesis and provide the foundations for developing new therapeutic approaches targeting HKMTs in cancers.

Automated summary

This review highlights the recent progress in structural studies of histone lysine methyltransferases (HKMTs), which play important roles in regulating chromatin structure and gene expression. The focus is on representative HKMTs (H3K4, H3K27, H3K36, H3K79, and H4K20 methyltransferases) in complex with nucleosomes, with emphasis on understanding the molecular mechanisms of nucleosome recognition and trans-histone crosstalk by these enzymes. These structural studies shed light on the roles of HKMTs in tumorigenesis and provide a basis for developing novel therapeutic approaches targeting HKMTs in cancer.