Journal of Biological Chemistry
Volume 279, Issue 53, 31 December 2004, Pages 55520-55530
Journal home page for Journal of Biological Chemistry

Genes: Structure and Regulation
Chromatin Domain Boundaries Delimited by a Histone-binding Protein in Yeast*

https://doi.org/10.1074/jbc.M410346200Get rights and content
Under a Creative Commons license
open access

When located next to chromosomal elements such as telomeres, genes can be subjected to epigenetic silencing. In yeast, this is mediated by the propagation of the SIR proteins from telomeres toward more centromeric regions. Particular transcription factors can protect downstream genes from silencing when tethered between the gene and the telomere, and they may thus act as chromatin domain boundaries. Here we have studied one such transcription factor, CTF-1, that binds directly histone H3. A deletion mutagenesis localized the barrier activity to the CTF-1 histone-binding domain. A saturating point mutagenesis of this domain identified several amino acid substitutions that similarly inhibited the boundary and histone binding activities. Chromatin immunoprecipitation experiments indicated that the barrier protein efficiently prevents the spreading of SIR proteins, and that it separates domains of hypoacetylated and hyperacetylated histones. Together, these results suggest a mechanism by which proteins such as CTF-1 may interact directly with histone H3 to prevent the propagation of a silent chromatin structure, thereby defining boundaries of permissive and silent chromatin domains.

Cited by (0)

*

This work was supported by the Swiss National Science Foundation, the Ligue Nationale Contre le Cancer, and Etat de Vaud. The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked “advertisement” in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.

The on-line version of this article (available at http://www.jbc.org) contains additional text and Fig. S1.

§

Both authors contributed equally to this work.