Epigenetic inheritance: histone bookmarks across generations

Abstract

Multiple circuitries ensure that cells respond correctly to the environmental cues within defined cellular programs. There is increasing evidence suggesting that cellular memory for these adaptive processes can be passed on through cell divisions and generations. However, the mechanisms by which this epigenetic information is transferred remain elusive largely because it requires that such memory survive through gross chromatin remodeling events during DNA replication, mitosis, meiosis and developmental reprogramming. Elucidating the processes by which epigenetic information survives and is transmitted is a central challenge in biology. Here we consider recent advances in understanding mechanisms of epigenetic inheritance with a focus on histone segregation at the replication fork and how an epigenetic memory may get passed through the paternal lineage.

Two distinct modes for propagation of histone PTMs across the cell cycle

“…Such a tight regulation of PTM establishment could limit unwarranted silencing, which is jeopardized in cancers carrying EZH2-activating mutations (McCabe et al 2012). Evidently, it will be important to consider the kinetics of PTM restoration in current models of epigenetic inheritance (Alabert and Groth 2012;Huang et al 2013;Campos et al 2014). We further envision that this mode of PTM maintenance could explain how cell cycle speed and withdrawal impact on cellular plasticity.…”

Low-Dose Gamma Irradiation Enhances Superoxide Anion Production by Nonirradiated Cells Through TGF-β1-Dependent Bystander Signaling

“…This is achieved by neutralizing the positive amine group present in lysine with amide conversion, thus reducing the interaction between the negatively charged DNA with the histone. Acetylation allows increased access to gene regulatory proteins and transcription factors leading to enhanced gene expression (36,37). HAT preferentially targets lysine residues within histones H3 and H4.…”

Human Adipocytes : Proteomic Approaches

“…Moreover, there is not much of hard evidence indicating a direct transfer of histone PTMs to daughter cells during mitosis and it seems even less is clear regarding meiosis. Models of inheritance are published (e.g in [176,177] Regardless of heritability, histone variants and PTMs could be one of the factors facilitating the rapid adjustments of gene transcription to a changing environment. And regardless of whether they are the cause or the consequence, histone modifications have been associated with for example long term hyperglycemic memory after restoration of normoglycemia [181,182], and with altered transcription of adipokines after in-utero high fat diet exposure [183].…”