H1-mediated Repression of Transcription Factor Binding to a Stably Positioned Nucleosome
| Autor: | Lothar Böhm, Marissa Vignali, Jerry L. Workman, Li-Jung Juan, Rhea T. Utley |
|---|---|
| Rok vydání: | 1997 |
| Předmět: |
Binding Sites
Restriction Mapping DNA Cell Biology Biology Biochemistry Molecular biology Linker DNA Upstream Stimulatory Factor Nucleosomes Cell biology Histones Recognition sequence Histone H1 Chromatosome biology.protein Humans Micrococcal Nuclease Nucleosome Histone octamer Molecular Biology HeLa Cells Transcription Factors Micrococcal nuclease |
| Zdroj: | Journal of Biological Chemistry. 272:3635-3640 |
| ISSN: | 0021-9258 |
| DOI: | 10.1074/jbc.272.6.3635 |
| Popis: | Previously, we reported that histone H1 binding to nucleosome cores results in the repression of binding of the basic helix-loop-helix upstream stimulatory factor (USF) (Juan, L.-J., Utley, R. T., Adams, C. C., Vettese-Dadey, M., and Workman, J. L. (1994) EMBO J. 13, 6031-6040). We have tested whether this inhibition resulted from H1-mediated changes in nucleosome positioning (Ura, K., Hayes, J. J., and Wolffe, A. P. (1995) EMBO J. 14, 3752-3765) forcing the USF recognition sequence into less accessible locations within the nucleosome. Nucleosome boundaries were determined by assays combining micrococcal nuclease and restriction endonuclease digestion. A unique pair of boundaries were observed, indicating a single nucleosome translational position. This nucleosome position did not change on H1 or USF binding. Thus, H1 repression of USF binding was independent of nucleosome mobility, indicating an alternative mechanism of H1 repression. H1 repressed USF binding at a site 35 base pairs into the nucleosome core more effectively than at a site near the "linker" DNA, suggesting that inhibition by H1 was not simply due to steric occlusion. Instead, these data are consistent with a model by which H1 binding reduces transient dynamic exposure of the DNA from the histone octamer surface (Polach, K. L., and Widom, J. (1995) J. Mol. Biol. 254, 130-149). |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|