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Updated: Jul 12, 2026
Expression Analysis of Mammalian Linker-histone Subtypes
Published on: March 19, 2012
Competition between linker histones and HMG1 for binding to four-way junction DNA: implications for transcription
P Varga-Weisz1, K van Holde, J Zlatanova
1Department of Biochemistry and Biophysics, Oregon State University, Corvallis 97331-7305.
Abstract:
Both lysine-rich histones and high mobility group proteins 1 and 2 bind to linker DNA in chromatin. While the members of the histone H1 class are considered general repressors of transcription, HMG1/2 are viewed as activators. Using stable four-way junction DNA as a model for cross-overs of linker DNA at the entry and exit to nucleosomes, we show that HMG1 can compete efficiently with H1 for binding to four-way junctions. In contrast, the erythrocyte-specific histone H5 seems to be refractory to displacement by HMG1. The results suggest that replacement of histone H1 by HMG1 may be part of the transcriptional activation by HMG1.
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