Metabolically Derived Lysine Acylations and Neighboring Modifications Tune the Binding of the BET Bromodomains to Histone H4. Biochemistry 2017 Oct 17;56(41):5485-5495
Date
09/26/2017Pubmed ID
28945351Pubmed Central ID
PMC5970795DOI
10.1021/acs.biochem.7b00595Scopus ID
2-s2.0-85031686253 (requires institutional sign-in at Scopus site) 19 CitationsAbstract
Recent proteomic studies discovered histone lysines are modified by acylations beyond acetylation. These acylations derive from acyl-CoA metabolites, potentially linking metabolism to transcription. Bromodomains bind lysine acylation on histones and other nuclear proteins to influence transcription. However, the extent bromodomains bind non-acetyl acylations is largely unknown. Also unclear are the effects of neighboring post-translational modifications, especially within heavily modified histone tails. Using peptide arrays, binding assays, sucrose gradients, and computational methods, we quantified 10 distinct acylations for binding to the bromodomain and extraterminal domain (BET) family. Four of these acylations (hydroxyisobutyrylation, malonylation, glutarylation, and homocitrullination) had never been tested for bromodomain binding. We found N-terminal BET bromodomains bound acetylated and propionylated peptides, consistent with previous studies. Interestingly, all other acylations inhibited binding of the BET bromodomains to peptides and nucleosomes. To understand how context tunes bromodomain binding, effects of neighboring methylation, phosphorylation, and acylation within histone H4 tails were determined. Serine 1 phosphorylation inhibited binding of the BRD4 N-terminal bromodomain to polyacetylated H4 tails by >5-fold, whereas methylation had no effect. Furthermore, binding of BRDT and BRD4 N-terminal bromodomains to H4K5acetyl was enhanced 1.4-9.5-fold by any neighboring acylation of lysine 8, indicating a secondary H4K8acyl binding site that is more permissive of non-acetyl acylations than previously appreciated. In contrast, C-terminal BET bromodomains exhibited 9.9-13.5-fold weaker binding for polyacylated than for monoacylated H4 tails, indicating the C-terminal bromodomains do not cooperatively bind multiple acylations. These results suggest acyl-CoA levels tune or block recruitment of the BET bromodomains to histones, linking metabolism to bromodomain-mediated transcription.
Author List
Olp MD, Zhu N, Smith BCAuthors
Brian C. Smith PhD Associate Professor in the Biochemistry department at Medical College of WisconsinNan Zhu PhD Assistant Professor in the Cell Biology, Neurobiology and Anatomy department at Medical College of Wisconsin
MESH terms used to index this publication - Major topics in bold
AcylationAnimals
Cell Cycle Proteins
Cell Line
Chickens
Histones
Ligands
Lysine
Methylation
Models, Molecular
Molecular Docking Simulation
Nuclear Proteins
Nucleosomes
Oligopeptides
Peptide Fragments
Phosphorylation
Protein Array Analysis
Protein Interaction Domains and Motifs
Protein Processing, Post-Translational
RNA-Binding Proteins
Recombinant Fusion Proteins
Transcription Factors
