Covalent modifications of histones, such as acetylation and methylation, play important roles in the regulation of gene expression. Histone lysine methylation has been implicated in both gene activation and repression, depending on the specific lysine (K) residue that becomes methylated and the state of methylation (mono-, di-, or trimethylation). Methylation on K4, K9, and K36 of histone H3 ha...

BACKGROUND Histone H3 lysine 9 (H3-K9) methylation and DNA methylation are characteristic hallmarks of mammalian heterochromatin. H3-K9 methylation was recently shown to be a prerequisite for DNA methylation in Neurospora crassa and Arabidopsis thaliana. Currently, it is unknown whether a similar dependence exists in mammalian organisms. RESULTS Here, we demonstrate a physical and functional ...

Histone methylation is widely present in animals, plants and fungi, and the methylation modification of histone H3 has important biological functions. Methylation of Lys9 of histone H3 (H3K9) has been proven to regulate chromatin structure, gene silencing, transcriptional activation, plant metabolism, and other processes. In this work, we investigated the functions of a H3K9 methyltransferase g...

The maintenance of a proper nuclear architecture and three-dimensional organization of the genes, enhancer elements, and transcription machinery plays an essential role in tissue development and regeneration. Here we show that in the developing skin, epidermal progenitor cells of mice lacking p63 transcription factor display alterations in the nuclear shape accompanied by a marked decrease in e...

In the ciliate Paramecium tetraurelia, differentiation of the somatic nucleus from the zygotic nucleus is characterized by massive and reproducible deletion of transposable elements and of 45,000 short, dispersed, single-copy sequences. A specific class of small RNAs produced by the germline during meiosis, the scnRNAs, are involved in the epigenetic regulation of DNA deletion but the underlyin...

PURPOSE PR (PRDI-BF1 and RIZ) domain proteins (PRDM) are a subfamily of the kruppel-like zinc finger gene products that play key roles during cell differentiation and malignant transformation. The aim of the present study was to begin to examine the involvement of epigenetic alteration of PRDM expression in gastric and colorectal cancer. EXPERIMENTAL DESIGN We used real-time PCR to assess exp...

Plant life-long organogenesis involves sequential, time and tissue specific expression of developmental genes. This requires activities of Polycomb Group (PcG) and trithorax Group complexes (trxG), respectively responsible for repressive Histone 3 trimethylation at lysine 27 (H3K27me3) and activation-related Histone 3 trimethylation at lysine 4 (H3K4me3). However, the genome-wide dynamics in hi...

In eukaryotes, the post-translational addition of methyl groups to histone H3 lysine 4 (H3K4) plays key roles in maintenance and establishment of appropriate gene expression patterns and chromatin states. We report here that an essential locus within chromosome 3L centric heterochromatin encodes the previously uncharacterized Drosophila melanogaster ortholog (dSet1, CG40351) of the Set1 H3K4 hi...

The consolidation of long-term memories requires differential gene expression. Recent research has suggested that dynamic changes in chromatin structure play a role in regulating the gene expression program linked to memory formation. The contribution of histone methylation, an important regulatory mechanism of chromatin plasticity that is mediated by the counteracting activity of histone-methy...

We report a detailed analysis of maize chromosome structure with respect to seven histone H3 methylation states (dimethylation at lysine 4 and mono-, di-, and trimethylation at lysines 9 and 27). Three-dimensional light microscopy and the fine cytological resolution of maize pachytene chromosomes made it possible to compare the distribution of individual histone methylation events to each other...