14-3-3 mediates histone cross-talk during transcription elongation in Drosophila

Post-translational modifications of histone proteins modulate the binding of transcription regulators to chromatin. studies in drosophila have shown that the phosphorylation of histone h3 at ser10 (h3s10ph) by jil-1 is required specifically during early transcription elongation. 14-3-3 proteins bind h3 only when phosphorylated,providing mechanistic insights into the role of h3s10ph in transcription. findings presented here show that 14-3-3 functions downstream of h3s10ph during transcription elongation. 14-3-3 proteins localize to active genes in a jil-1-dependent manner. in the absence of 14-3-3,levels of actively elongating rna polymerase ii are severely diminished. 14-3-3 proteins interact with elongator protein 3 (elp3),an acetyltransferase that functions during transcription elongation. jil-1 and 14-3-3 are required for elp3 binding to chromatin,and in the absence of either protein,levels of h3k9 acetylation are significantly reduced. these results suggest that 14-3-3 proteins mediate cross-talk between histone phosphorylation and acetylation at a critical step in transcription elongation. © 2010 karam et al.