title: Organismal differences in post-translational modifications in histones H3 and H4.
abstract: Post-translational modifications (PTMs) of histones play an important role in many cellular processes, notably gene regulation. Using a combination of mass spectrometric and immunobiochemical approaches, we show that the PTM profile of histone H3 differs significantly among the various model organisms examined. Unicellular eukaryotes, such as Saccharomyces cerevisiae (yeast) and Tetrahymena thermophila (Tet), for example, contain more activation than silencing marks as compared with mammalian cells (mouse and human), which are generally enriched in PTMs more often associated with gene silencing. Close examination reveals that many of the better-known modified lysines (Lys) can be either methylated or acetylated and that the overall modification patterns become more complex from unicellular eukaryotes to mammals. Additionally, novel species-specific H3 PTMs from wild-type asynchronously grown cells are also detected by mass spectrometry. Our results suggest that some PTMs are more conserved than previously thought, including H3K9me1 and H4K20me2 in yeast and H3K27me1, -me2, and -me3 in Tet. On histone H4, methylation at Lys-20 showed a similar pattern as H3 methylation at Lys-9, with mammals containing more methylation than the unicellular organisms. Additionally, modification profiles of H4 acetylation were very similar among the organisms examined.
authors.affiliation: Department of Chemistry, University of Virginia, Charlottesville, Virginia 22901, USA.
authors.forename: Benjamin A
authors.initials: BA
authors.lastname: Garcia
authors.forename: Sandra B
authors.initials: SB
authors.lastname: Hake
authors.forename: Robert L
authors.initials: RL
authors.lastname: Diaz
authors.forename: Monika
authors.initials: M
authors.lastname: Kauer
authors.forename: Stephanie A
authors.initials: SA
authors.lastname: Morris
authors.forename: Judith
authors.initials: J
authors.lastname: Recht
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Shabanowitz
authors.forename: Nilamadhab
authors.initials: N
authors.lastname: Mishra
authors.forename: Brian D
authors.initials: BD
authors.lastname: Strahl
authors.forename: C David
authors.initials: CD
authors.lastname: Allis
authors.forename: Donald F
authors.initials: DF
authors.lastname: Hunt
mesh_terms: D000107:Acetylation; D000818:Animals; D006367:HeLa Cells; D006657:Histones / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D008745:Methylation; D051379:Mice; D041681:NIH 3T3 Cells; D011499:Protein Processing, Post-Translational; D012441:Saccharomyces cerevisiae / Q000378:metabolism; D013045:Species Specificity; D053719:Tandem Mass Spectrometry; D013768:Tetrahymena / Q000378:metabolism
chemical_list: D006657:Histones