Search results for "Histone"

Histones and non-histone proteins during sea urchin development

1979

Abstract Chromatin from blastulae and plutei of Paracentrotus lividus was fractionated through a hydroxyapatite column. The ratio of histones versus non-histone proteins decreases from blastula to pluteus stage.

Functional characterization of the enhancer blocking element of the sea urchin early histone gene cluster reveals insulator properties and three esse…

2000

Insulator elements can be functionally identified by their ability to shield promoters from regulators in a position-dependent manner or their ability to protect adjacent transgenes from position effects. We have previously reported the identification of a 265 bp sns DNA fragment at the 3' end of the sea urchin H2A early histone gene that blocked expression of a reporter gene in transgenic embryos when placed between the enhancer and the promoter. Here we show that sns interferes with enhancer-promoter interaction in a directional manner. When sns is placed between the H2A modulator and the inducible tet operator, the modulator is barred from interaction with the basal promoter. However, th…

Histone Deacetylase Inhibitors

2020

Histone deacetylases (HDACs) are key components of the epigenetic machinery controlling gene expression. They are involved in chromatin remodeling events via post-translational histone modifications but may also act on nonhistone proteins, influencing many fundamental cellular processes. Due to the key involvement of HDACs in serious human pathologies, including cancer, HDAC inhibitors (HDACis) have received increased attention in recent years. It is known that marine invertebrates produce significant amounts of secondary metabolites showing active pharmacological properties and an extensive spectrum of biomedical applications. Some of these compounds possess HDACi properties.

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…

Carbocysteine reverses the effects of cigarette smoke and improves the effects of beclomethasone on the histone deacetylases in bronchial epithelial …

2015

Cigarette smoke exposure, increasing oxidative stress, may negatively affect histone deacetylase expression/activity. Histone deacetylase expression/activity and in particular HDAC2, HDAC3, and SIRT-1 may control inflammation, cell senescence and responses to corticosteroids. The effects of carbocysteine and of beclomethasone on the histone deacetylase expression/activity in human bronchial epithelial cells stimulated with cigarette smoke extracts (CSE) are largely unknown. This study was aimed to explore whether carbocysteine and beclomethasone, in a bronchial epithelial cell line (16-HBE) exposed to CSE, were able to modulate the expression/activity of HDAC2, HDAC3, and of SIRT-1. Methods…

The Histone Acetyl-Transferase MOZ Cooperates with the Histone Methyl-Transferase MLL to Regulate HOX Gene Expression in Human Hematopoietic Stem Cel…

2008

Abstract MOZ (MOnocytic leukaemia Zinc finger protein) (also called MYST3 or KAT6A) is a member of the MYST family of HATs which likely acetylate H4K16. The MLL (MixedLineageLeukemia) gene is a frequent target for recurrent chromosomal translocations found in AML and ALL. MLL (KMT2A) is a methyl-transferase targeting H3K4. It was shown that MOZ/CBP leukemia, as observed in MLL-rearranged leukemias, harbors abnormal levels of homeobox (HOX) genes expression. HOX transcription factors have a crucial function in hematopoiesis regulation. In addition, HOXA5, HOXA7, and HOXA9 are often considered to be pivotal HOX genes for MLL transformation, constituting downstream targets of MLL. In our study…

In vivo assembly of chromatin on pBR322 sequences cloned into yeast plasmids

1989

Abstract In order to study the in vivo assembly of chromatin on prokaryotic DNA templates, we have transformed yeast cells with plasmids pAJ50 and pRB58, which contain pBR322 sequences. In both cases nucleosomes are assembled in vivo on pBR322 DNA, although the nucleosomes are not homogeneous in size. To explore whether there is any preference for nucleosome assembly along pBR322 sequences, we have used an indirect end labeling method. The results indicate that most nucleosomes are placed at random on pBR322, although the probability for histone octamers to interact with some short regions is somewhat reduced. These regions coincide with sequences in which the frequency distribution of nucl…

Circulating Histones and Nucleosomes as Biomarkers in Sepsis and Septic Shock

2016

Sepsis, severe sepsis, and septic shock are among the leading causes of death worldwide and their incidence is constantly increasing. Despite early intervention in intensive care units (ICUs) mortality remains high. There is great interest in understanding the genetics and epigenetics of the host in response to infection because of two reasons: the peculiarities of each patient, and the unclear associations identified between genetic polymorphisms and susceptibility to sepsis. In addition, chromatin remodeling and epigenetic changes occur in crucial genes involved in the inflammatory response and also in the immunosuppression found in sepsis. The early and accurate diagnosis of sepsis is a …

JAHA, a novel histone deacetylase inhibitor: cytotoxic effect on triple-negative breast cancer cells

2013

Pleiotropic antitumor effects of the pan-HDAC inhibitor ITF2357 against c-Myc-overexpressing human B-cell non-Hodgkin lymphomas,

2014

Histone deacetylases (HDAC) extensively contribute to the c-Myc oncogenic program, pointing to their inhibition as an effective strategy against c-Myc-overexpressing cancers. We, thus, studied the therapeutic activity of the new-generation pan-HDAC inhibitor ITF2357 (Givinostat®) against c-Myc-overexpressing human B-cell non-Hodgkin lymphomas (B-NHLs). ITF2357 anti-proliferative and pro-apoptotic effects were analyzed in B-NHL cell lines with c-Myc translocations (Namalwa, Raji and DOHH-2), stabilizing mutations (Raji) or post-transcriptional alterations (SU-DHL-4) in relationship to c-Myc modulation. ITF2357 significantly delayed the in vitro growth of all B-NHL cell lines by inducing G1 c…