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Updated: Jul 24, 2026

Expression Analysis of Mammalian Linker-histone Subtypes
Published on: March 19, 2012
Efficient transcription of a DNA template associated with histone (H3.H4)2 tetramers
C Puerta1, F Hernández, C Gutiérrez
1Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas, Madrid, Spain.
Abstract:
A histone-DNA transcription template has been assembled, by dialysis against decreasing salt concentrations, from pGEMEX-1 (4 kilobases), a plasmid containing a promoter for bacteriophage T7 RNA polymerase, and from isolated histone (H3.H4)2 tetramers. Electron microscopy after psoralen cross-linking shows that each histone tetramer protects approximately 80 base pairs of DNA from psoralen action and that, under the employed conditions, an average of 15 tetramer particles are assembled per DNA molecule. This (H3.H4)2-DNA template is efficiently transcribed in vitro by T7 RNA polymerase as compared to naked DNA. The presence of (H3.H4)2 tetramers does not affect initiation, in contrast with the complete histone octamer, (H2A.H2B.H3.H4)2, assembled with the complementary addition of H2A.H2B dimers, which causes transcriptional inhibition mainly by blocking initiation.
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