0000000000134724
AUTHOR
Manuel Boix-chornet
Release of Hypoacetylated and Trimethylated Histone H4 Is an Epigenetic Marker of Early Apoptosis
11 p.-5 fig.-1 fig. supl.
Epigenetic differences arise during the lifetime of monozygotic twins.
Monozygous twins share a common genotype. However, most monozygotic twin pairs are not identical; several types of phenotypic discordance may be observed, such as differences in susceptibilities to disease and a wide range of anthropomorphic features. There are several possible explanations for these observations, but one is the existence of epigenetic differences. To address this issue, we examined the global and locus-specific differences in DNA methylation and histone acetylation of a large cohort of monozygotic twins. We found that, although twins are epigenetically indistinguishable during the early years of life, older monozygous twins exhibited remarkable differences in their overall…
Conformational Changes in the Nucleosome Followed by the Selective Accessibility of Histone Glutamines in the Transglutaminase Reaction: Effects of Ionic Strength
Transglutaminases, the enzymes that catalyze the acyl-transfer reaction between glutamine and primary amines, have been used to introduce probes into proteins in order to perform structural studies using physical techniques. Here we use an original approach in which the increasing accessibility of the glutamines of core histones to TGase is used to monitor the salt-induced conformational changes of the nucleosome. The rationale of this strategy is that the accessibility of a glutamine to transglutaminase depends on the blockage due to the presence of either other histones or DNA. At low ionic strength, only glutamines on the N-terminal tails of H2B and H3 are labeled with monodansylcadaveri…