Signals and Combinatorial Functions of Histone Modifications

Abstract

Alterations of chromatin structure have been shown to be crucial for response to cell signaling and for programmed gene expression in development. Posttranslational histone modifications influence changes in chromatin structure both directly and by targeting or activating chromatin-remodeling complexes. Histone modifications intersect with cell signaling pathways to control gene expression and can act combinatorially to enforce or reverse epigenetic marks in chromatin. Through their recognition by protein complexes with enzymatic activities cross talk is established between different modifications and with other epigenetic pathways, including noncoding RNAs (ncRNAs) and DNA methylation. Here, we review the functions of histone modifications and their exploitation in the programming of gene expression during several events in development.

Coordinate Changes in Histone Modifications, mRNA Levels, and Metabolite Profiles in Clonal INS-1 832/13 β-Cells Accompany Functional Adaptations to Lipotoxicity

“…Three of the analyzed histone modifications are associated with transcriptional activation (H3K9Ac, H3K79me2, and H3K4me3) and one modification is associated with transcriptional repression (H3K27me3) (28,31,47,48). We then selected 10 genes from the top hits of the microarray results for quantitative analysis of histone modifications, using qRT-PCR.…”

Ordered changes in histone modifications at the core of the Arabidopsis circadian clock

“…Histone methylation, on the other hand, may facilitate the recruitment of chromatin remodeling factors that can either activate or repress transcription, depending on the particular residue that is methylated and the degree of methylation (4). The sequential or combinatorial composition of these histone modifications facilitates the switch between permissive and repressive states of chromatin that ultimately modulate the genome activity in eukaryotes (5).…”

Regulation of Primary Response Genes in B Cells

“…Chen and Allfrey (15) were the first to provide a correlation between alterations in chromatin architecture, histone acetylation, and PRG (c-fos and c-myc) transcription. Since then, numerous studies have addressed specific chromatin changes in eukaryotic genes, including PRGs (42)(43)(44)(45). Although the mRNA-encoding PRGs usually constitute ϳ1% of the total message in the growing cell, they are necessary to drive cells to re-enter the cell cycle (1).…”