title: Mutations that prevent or mimic persistent post-translational modifications of the histone H3 globular domain cause lethality and growth defects in Drosophila.
abstract: BACKGROUND
  Understanding the function of histone post-translational modifications is the key to deciphering how genomic activities are regulated. Among the least well-understood histone modifications in vivo are those that occur on the surface of the globular domain of histones, despite their causing the most profound structural alterations of the nucleosome in vitro. We utilized a Drosophila system to replace the canonical histone genes with mutated histone transgenes.
  
  
  RESULTS
  Mutations predicted to mimic or prevent acetylation on histone H3 lysine (K) 56, K115, K122, and both K115/K122, or to prevent or mimic phosphorylation on H3 threonine (T) 118 and T80, all caused lethality, with the exception of K122R mutants. T118 mutations caused profound growth defects within wing discs, while K115R, K115Q, K56Q, and the K115/K122 mutations caused more subtle growth defects. The H3 K56R and H3 K122R mutations caused no defects in growth, differentiation, or transcription within imaginal discs, indicating that H3 K56 acetylation and K122 acetylation are dispensable for these functions. In agreement, we found the antibody to H3 K122Ac, which was previously used to imply a role for H3 K122Ac in transcription in metazoans, to be non-specific in vivo.
  
  
  CONCLUSIONS
  Our data suggest that chromatin structural perturbations caused by acetylation of K56, K115, or K122 and phosphorylation of T80 or T118 are important for key developmental processes.
authors.affiliation: Department of Epigenetics and Molecular Carcinogenesis, University of Texas MD Anderson Cancer Center, Houston, TX 77030 USA.
authors.forename: Hillary K
authors.initials: HK
authors.lastname: Graves
authors.affiliation: Department of Epigenetics and Molecular Carcinogenesis, University of Texas MD Anderson Cancer Center, Houston, TX 77030 USA ; Department of Pathology and Laboratory Medicine, Weill Cornell Medical College, New York, NY 10065 USA.
authors.forename: Pingping
authors.initials: P
authors.lastname: Wang
authors.affiliation: Department of Epigenetics and Molecular Carcinogenesis, University of Texas MD Anderson Cancer Center, Houston, TX 77030 USA.
authors.forename: Matthew
authors.initials: M
authors.lastname: Lagarde
authors.affiliation: Department of Epigenetics and Molecular Carcinogenesis, University of Texas MD Anderson Cancer Center, Houston, TX 77030 USA.
authors.forename: Zhihong
authors.initials: Z
authors.lastname: Chen
authors.affiliation: Department of Epigenetics and Molecular Carcinogenesis, University of Texas MD Anderson Cancer Center, Houston, TX 77030 USA ; Department of Pathology and Laboratory Medicine, Weill Cornell Medical College, New York, NY 10065 USA.
authors.forename: Jessica K
authors.identifier: 0000-0001-9765-1659
authors.initials: JK
authors.lastname: Tyler
keywords: Development; Drosophila; Histone H3 globular domain; Histone post-translational modifications; Imaginal discs