Eukaryotic genomes contain euchromatic regions, which are transcriptionally active, and heterochromatic regions, which are repressed. These domains are separated by "barrier elements": DNA sequences that protect euchromatic regions from encroachment by neighboring heterochromatin. To identify proteins that play a role in the function of barrier elements we have carried out a screen in S. cerevi...

Packaging of eukaryotic genomes into chromatin has wide-ranging effects on gene transcription. Curiously, it is commonly observed that deletion of a global chromatin regulator affects expression of only a limited subset of genes bound to or modified by the regulator in question. However, in many single-gene studies it has become clear that chromatin regulators often do not affect steady-state t...

It is becoming more evident that histone acetylation, as one of the epigenetic modifications or markers, plays a key role in the etiology of Alzheimer's disease (AD). Histone acetylases and histone deacetylases (HDACs) are the well-known covalent enzymes that modify the reversible acetylation of lysine residues in histone amino-terminal domains. In AD, however, the roles of these enzymes are co...

microglia is the effector cell of the innate immune system in central nervous system (cns). these cells mediate inflammatory responses in injuries. besides external factors, microglial function is also controlled by internal factors, including epigenetic regulations. mechanisms of epigenetic regulation mainly consist of dna methylation, histone modifications and use of non-coding rnas. recent s...

histone deacetylases (hdacs) are the enzymes causing deacetylation of histone and non-histone substrates. histone deacetylase inhibitors (hdis) are a family of drugs eliminating the effect of hdacs in malignant cells via inhibition of hdacs. due to extensive effects upon gene expression through interference with fusion genes and transcription factors, hdacs cause proliferation and migration of ...

Histone lysine methylation is a central modification to mark functionally distinct chromatin regions. In particular, H3-K9 trimethylation has emerged as a hallmark of pericentric heterochromatin in mammals. Here we show that H4-K20 trimethylation is also focally enriched at pericentric heterochromatin. Intriguingly, H3-K9 trimethylation by the Suv39h HMTases is required for the induction of H4-...

Small ubiquitin-like modifier (SUMO), a reversible post-translational protein modifier, plays important roles in diverse cellular mechanisms. Three enzymes, E1 (activating enzyme), E2 (conjugating enzyme) and E3 (ligase), are involved in SUMO modification. SUMOylation system and process in higher eukaryotes have been well studied. However, in protozoa, such as Trypanosoma brucei (T. brucei), th...

Background: Epigenetic modifications are involved in different cellular processes through regulating chromatin dynamics. histone methylation is an important modification that can be dynamically regulated by histone methyltransferase and histone demethylase enzymes. JMJD1A (also known as JHDM2A and KDM3A) is a histone demethylase specific for H3K9me2/me1. JMJD1A is a key epigenetic regulator tha...

Two forms of a histone H1-specific S-adenosylmethionine:protein-lysine N-methyltransferase (protein methylase III) have been purified from Euglena gracilis 48- and 214-fold, respectively, with yields of 3.4 and 4.6%. The enzymes were purified on DEAE-cellulose and histone-Sepharose affinity chromatography and found to be highly specific toward histone H1 as a substrate. However, one of the enzy...