Search results for "Chromatosome"
showing 3 items of 3 documents
Acetylated nucleosome assembly on telomeric DNAs
2003
Abstract The role of histone N-terminal domains on the thermodynamic stability of nucleosomes assembled on several different telomeric DNAs as well as on ‘average’ sequence DNA and on strong nucleosome positioning sequences, has been studied by competitive reconstitution. We find that histone tails hyperacetylation favors nucleosome formation, in a similar extent for all the examined sequences. On the contrary, removal of histone terminal domains by selective trypsinization causes a decrease of nucleosome stability which is smaller for telomeres compared to the other sequences examined, suggesting that telomeric sequences have only minor interactions with histone tails. Micrococcal nuclease…
Nucleosome-specific, Time-dependent Changes in Histone Modifications during Activation of the Early Growth Response 1 (Egr1) Gene
2014
Histone post-translational modifications and nucleosome remodeling are coordinate events involved in eukaryotic transcriptional regulation. There are relatively few data on the time course with which these events occur in individual nucleosomes. As a contribution to fill this gap, we first describe the nature and time course of structural changes in the nucleosomes -2, -1, and +1 of the murine Egr1 gene upon induction. To initiate the transient activation of the gene, we used the stimulation of MLP29 cells with phorbol esters and the in vivo activation after partial hepatectomy. In both models, nucleosomes -1 and +1 are partially evicted, whereas nucleosomes +1 and -2 slide downstream durin…
Use of the Transglutaminase Reaction To Study the Dissociation of Histone N-Terminal Tails from DNA in Nucleosome Core Particles
1997
We have recently shown that core histones are glutaminyl substrates for transglutaminase (TGase) and that when native nucleosome cores are incubated with monodansylcadaverine (DNC) as donor amine, this fluorescent probe is incorporated into Gln5 and Gln19 of H3 and in Gln22 of H2B [Ballestar et al. (1996) J. Biol. Chem. 271, 18817-18825]. In the present paper, we report that the cause by which Gln22 of H2B is modified in nucleosomes but not in the free histone is the interaction of the region containing that glutamine with DNA. We have used the specificity of the TGase reaction to study the changes induced by increasing ionic strength in the interaction between the histone N-terminal tails …