Transcriptional Properties of Oligonucleosomal Templates Containing Acetylated (H3·H4) 2 Tetramers

• Published in: Biochemical and biophysical research communications 1995-08, Vol.213 (1), p.232-238
• Main Authors: Hernandez, F., Puerta, C., Lopezalarcon, L., Palacian, E.
• Format: Article
• Language: English
• Subjects: Acetylation; Bacteriophage T7 - enzymology; Chromatography, Gel; Cytidine Triphosphate - metabolism; DNA-Directed RNA Polymerases - metabolism; Histones - isolation & purification; Histones - metabolism; Kinetics; Lysine; Macromolecular Substances; Nucleosomes - metabolism; Plasmids; Templates, Genetic; Transcription, Genetic; Viral Proteins
• ISSN: 0006-291X; 1090-2104
• DOI: 10.1006/bbrc.1995.2121

Direct chemical acetylation of an oligonucleosomal template for bacteriophage T7 RNA polymerase is accompanied by a substantial increase in its capability to support RNA synthesis. The template was assembled from a plasmid, containing a promoter and a terminator for T7 RNA polymerase, plus one (H3·H4) 2 tetramer and two H2A·H2B dimers for each 200 base pairs of DNA. Under the employed conditions, acetylation modifies in a preferential way the lysine residues located in the amino-terminal domains of core histones. When the template is assembled with acetylated tetramers and untreated dimers, its efficiency in promoting RNA synthesis is also largely increased. Since a previous work reported transcriptional stimulation upon acetylation of H2A·H2B dimers [Puerta et al. (1995) Biochem. Biophys. Res. Commun. 210, 409], the transcriptional repression brought about by core histone octamers seems to require that the amino-terminal domains of both (H3·H4) 2 tetramers and H2A·H2B dimers are not acetylated.