Postsynthetic acetylation of histones during the cell cycle: a general function for the displacement of histones during chromatin rearrangements

• Published in: Nucleic acids research Vol. 15; no. 20; pp. 8351 - 8366
• Main Authors: LOIDL, P, GRÖBNER, P
• Format: Journal Article
• Language: English
• Published: Oxford Oxford University Press 26-10-1987
• Subjects: Acetates - metabolism; Acetic Acid; Acetylation; Biological and medical sciences; Cell Cycle; Chromatin - ultrastructure; Chromatin. Chromosome; Fundamental and applied biological sciences. Psychology; Histones - genetics; Lysine - metabolism; Mitosis; Molecular and cellular biology; Molecular genetics; Physarum; Physarum - cytology; Physarum - genetics; Protein Processing, Post-Translational; Tritium; Protozoa; Chromatin; Vegetals; Physarum polycephalum; Nucleosome; Post translational modification; Regulation(control); Supramolecular structure; Cell cycle; Molecular rearrangement; Acetylation; Histone; Mycetozoa
• ISSN: 0305-1048; 1362-4962
• DOI: 10.1093/nar/15.20.8351

Postsynthetic acetylation of core histones exhibits a peak during S-phase of the Physarum cell cycle. The maximum 3H-acetate incorporation precedes the maximum of histone synthesis. Acetate is incorporated into all core histones during S-phase, but only into H2A and H2B during G2-period. Resolution of acetylated H4-subspecies reveals acetate incorporation into preexisting H4, but not into newly synthesized molecules during mitosis and early S-phase. In a protamine competition assay histones from S-phase chromatin are released at lower protamine concentrations as compared to the lower acetylated G2-chromatin. We demonstrate a preferential release of highly acetylated H4-subspecies at low protamine concentrations. Our results fit into a general model of the relationship between histone acetylation and chromatin assembly. According to this model acetylation of core histones would serve as a signal for displacement of histones from nucleosomes by modulating histone-protein or histone-DNA interactions. We propose that this mechanism operates during DNA-replication and transcription, as well as during other chromatin rearrangements.