An archaeal SET domain protein exhibits distinct lysine methyltransferase activity towards DNA-associated protein MC1-α

摘要: The evolutionarily conserved SET domain proteins in eukaryotes have been shown to function as site-specific histone lysine methyltransferases, and play an important role regulating chromatin-mediated gene transcriptional activation silencing. Structure-based sequence analysis has revealed that domains are also encoded by viruses bacteria, well Archaea. However, their cellular functions remain elusive. In this study, we characterized a protein from Methanosarcina mazei strain Go1 refer Go1-SET. We show Go1-SET exists homodimer solution, methyltransferase with high substrate specificity is dependent on the amino acid flanking methylation site. Particularly, exhibits selective activity towards one of major archaeal DNA interacting MC1-alpha at 37. Our findings suggest such may restructure chromatin composed MC1-DNA complexes, modulation structure arisen before divergence eukaryotic lineages.