CTCF induces histone variant incorporation, erases the H3K27me3 histone mark and opens chromatin.
Bottom Line: The insulator factor, CTCF, has been found to bind to boundaries and to mediate insulator function.This demonstrates the causal role for CTCF in generating the chromatin features found at insulators.Thereby, spreading of a histone modification from one domain through the insulator into the neighbouring domain is inhibited.
Affiliation: Institute for Genetics, Justus-Liebig-University, 35392 Giessen, Germany.Show MeSH
Related in: MedlinePlus
Mentions: Together these results suggest that the rapid removal of the H3K27me3 mark, which precedes chromatin opening as tested with the LacO array model, is at least in part mediated by the transient incorporation of H3.3. This is supported by the analysis of endogenous CTCF/H3.3 sites, which show a reduced H3.3 incorporation upon CTCF depletion. Thus, it can be envisaged (Figure 9) that CTCF incorporates H3.3, which causes depletion of stable nucleosomes and thereby interferes with spreading of the repressive marks into the active domain.
Affiliation: Institute for Genetics, Justus-Liebig-University, 35392 Giessen, Germany.