Search results for " histone variants"

Histones, Their Variants and Post-translational Modifications in Zebrafish Development.

2020

Complex multi-cellular organisms are shaped starting from a single-celled zygote, owing to elaborate developmental programs. These programs involve several layers of regulation to orchestrate the establishment of progressively diverging cell type-specific gene expression patterns. In this scenario, epigenetic modifications of chromatin are central in influencing spatiotemporal patterns of gene transcription. In fact, it is generally recognized that epigenetic changes of chromatin states impact on the accessibility of genomic DNA to regulatory proteins. Several lines of evidence highlighted that zebrafish is an excellent vertebrate model for research purposes in the field of developmental ep…

Replication-independent expression of H1˚ and H3.3 histone variants is probably regulated by different RNA-binding proteins

2012

DNA in eukaryotes is wrapped around core histones to form nucleosomes, the basic units of chromatin. The linker histones H1 bind DNA where it enters and leaves the nucleosome, thus stabilizing higher order structures. Chromatin is a dynamic complex, modulated by different processes such as DNA-methylation, post-translational modifications of histones, and incorporation of specific histone variants. Throughout rat brain development, expression of H1° and H3.3 histone variants is mainly regulated at the post-transcriptional level. These proteins are of interest for their possible involvement in the replication-independent chromatin remodelling induced by extracellular stimuli. We previously c…

Oligodendroglioma cells synthesize the differentiation-specific linker histone H1˚ and release it into the extracellular environment through shed ves…

2013

Chromatin remodelling can be involved in some of the epigenetic modifications found in tumor cells. One of the mechanisms at the basis of chromatin dynamics is likely to be synthesis and incorporation of replacement histone variants, such as the H1° linker histone. Regulation of the expression of this protein can thus be critical in tumorigenesis. In developing brain, H1° expression is mainly regulated at the post-transcriptional level and RNA-binding proteins (RBPs) are involved. In the past, attention mainly focused on the whole brain or isolated neurons and little information is available on H1° expression in other brain cells. Even less is known relating to tumor glial cells. In this st…

Histone H1° and H3.3 RNA-binding proteins identified in the developing rat brain

2011

Histone H1° RNA-binding proteins in developing rat brain.

2011

Purification by affinity chromatography of H1 RNA-Binding Proteins from rat brain

2003

Post-transcriptional regulation of mRNA metabolism is involved in processes as different as cell fate specification in development and cell response to a large variety of environmental cues. Regulation of all steps of RNA metabolism depends on RNA-binding proteins (RBPs). By using a T1 RNase protection assay, we previously identified three H1° RNA-binding factors (p40, p70 and p110), highly expressed in the rat brain. Here we report enrichment of these factors from brain extracts, obtained by affinity chromatography of biotinylated H1° RNA-protein complexes on streptavidin-conjugated paramagnetic particles. The purified proteins maintain RNA-binding ability and preference for histone messag…

RNA-binding activity of the rat calmodulin-binding PEP-19 protein and of the long PEP-19 isoform

2012

Synthesis of H1˚ histone protein, in the developing rat brain, seems to be regulated mainly at the post-transcriptional level. Since regulation of RNA metabolism depends on a series of RNA-binding proteins, we have been searching for RNA-binding proteins involved in the post-transcriptional regulation of the H1˚ gene. We recently reported isolation, from a cDNA expression library, of an insert encoding a novel protein, the C-terminal half of which is identical to that of PEP-19, a brain-specific protein involved in calcium metabolism. The novel protein was called long PEP-19 isoform (LPI). Herein we show that LPI, as well as PEP-19, can bind H1˚ RNA. Moreover, in order to improve production…

Histone macroH2A1.2 promotes metabolic health and leanness by inhibiting adipogenesis

2016

Background Obesity has tremendous impact on the health systems. Its epigenetic bases are unclear. MacroH2A1 is a variant of histone H2A, present in two alternatively exon-spliced isoforms macroH2A1.1 and macroH2A1.2, regulating cell plasticity and proliferation, during pluripotency and tumorigenesis. Their role in adipose tissue plasticity is unknown. Results Here, we show evidence that macroH2A1.1 protein levels in the visceral adipose tissue of obese humans positively correlate with BMI, while macroH2A1.2 is nearly absent. We thus introduced a constitutive GFP-tagged transgene for macroH2A1.2 in mice, and we characterized their metabolic health upon being fed a standard chow diet or a hig…