The fidelity of epigenetic inheritance or, the precision by which epigenetic information is passed trans-cell generations, is an essential parameter for measuring the effectiveness of the process. How the precision of the process is achieved or modulated, however, remains largely elusive.

Professor Xiangwei He’s group has performed quantitative measurement of epigenetic fidelity, using position effect variegation (PEV) in Schizosaccharomycespombe as readout, to explore whether replication perturbation affects nucleosome-mediated epigenetic inheritance. In their study, they showed that replication stresses reduce the fidelity of nucleosome-mediated epigenetic inheritance in fission yeast as well as multi-cellular organisms. And they provide evidence suggesting that excessive formation of single-stranded DNA correlates with the reduction in fidelity of centromeric chromatin duplication and may provide a mechanistic link between replication stresses and perturbations in epigenetic inheritance. Together, their results shed light on the importance of replication stresses cause epigenetic instability in addition to genetic stability.

Link：http://journals.plos.org/plosgenetics/article/authors?id=10.1371/journal.pgen.1006900