Identification of Lysine 37 of Histone H2B as a Novel Site of Methylation

Texas A&M University, United States of America
PLoS ONE (Impact Factor: 3.23). 01/2011; 6(1):e16244. DOI: 10.1371/journal.pone.0016244
Source: PubMed


Recent technological advancements have allowed for highly-sophisticated mass spectrometry-based studies of the histone code, which predicts that combinations of post-translational modifications (PTMs) on histone proteins result in defined biological outcomes mediated by effector proteins that recognize such marks. While significant progress has been made in the identification and characterization of histone PTMs, a full appreciation of the complexity of the histone code will require a complete understanding of all the modifications that putatively contribute to it. Here, using the top-down mass spectrometry approach for identifying PTMs on full-length histones, we report that lysine 37 of histone H2B is dimethylated in the budding yeast Saccharomyces cerevisiae. By generating a modification-specific antibody and yeast strains that harbor mutations in the putative site of methylation, we provide evidence that this mark exist in vivo. Importantly, we show that this lysine residue is highly conserved through evolution, and provide evidence that this methylation event also occurs in higher eukaryotes. By identifying a novel site of histone methylation, this study adds to our overall understanding of the complex number of histone modifications that contribute to chromatin function.

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    • "The novel types of modifications include tyrosine hydroxylation [30], serine and threonine acetylation [32], lysine crotonylation (Kcr) [30], lysine N-formylation [33], lysine succinylation [34], lysine malonylation [34], lysine propionylation [35], lysine butyrylation [35], O-GlcNAcylation (beta-N-acetylglucosamine) [36-38], lysine 5-hydroxylation [39] and cysteine glutathionylation [40]. Novel sites include Ub [41], phosphorylation [42,43], ADP-ribosylation [44], lysine acetylation and mono-, di- and tri- lysine methylations [30,45]. The degree of characterization varies for each PTM identified; however, there are some interesting findings and themes that emerge. "
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