in this study calf thymus chromatin was fractionated into active (s1 and s2) and inactive (p 2) chromatin. then the interaction of an anthracyc1ine antibiotic, adriamycin, with these fractions was investigated employing absorption and difference uv nis spectroscopy and sds and agarose gel electrophoreses. the results suggest that the binding of adriamycin to the s 1 fraction is slight but s2 an...

in this study the effect of a methylated derivative of nitrogen mustard (mechloroethamin) on solubilized and reconstituted chromatin was investigated using uvnis spectroscopy, dna and sds gel electrophoresis and densitomeoic scanning techniques, the results indicated that the 210 and 260 nm absorbances of reconstituted chromatin were decreased in a dose-dependent manner after treatment with var...

macroH2A is an H2A variant with a highly unusual structural organization. It has a C-terminal domain connected to the N-terminal histone domain by a linker. Crystallographic and biochemical studies show that changes in the L1 loop in the histone fold region of macroH2A impact the structure and potentially the function of nucleosomes. The 1.6-A X-ray structure of the nonhistone region reveals an...

Four different histones (H2A, H2B, H3, and H4; two subunits each) constitute a histone octamer, around which DNA wraps to form histone-DNA complexes called nucleosomes. Amino acid residues in each histone are occasionally modified, resulting in several biological effects, including differential regulation of transcription. Core promoters that encompass the transcription start site have well-con...

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...

We demonstrate using a dinucleosome template that acetylation of the core histones enhances transcription by RNA polymerase III. This effect is not dependent on an increased mobility of the core histone octamer with respect to DNA sequence. When linker histone is subsequently bound, we find both a reduction in nucleosome mobility and a repression of transcription. These effects of linker histon...

Recent studies report that the frictional resistance of partially acetylated core particles increases when the number of acetyl groups/particle exceeds 10 (Bode, J., Gomez-Lira, M. M. & Schröter, H. (1983) Eur. J. Biochem. 130, 437-445). This was attributed to an opening of the core particle though other explanations, e.g. unwinding of the DNA ends were also suggested. Another possible explanat...

Chemically induced histone-DNA crosslinking in nuclei is used to monitor structural changes in chromosomal domains containing hyperacetylated histones. Core particles harbouring the crosslinks are immunofractionated with antibodies specific for acetylated histones. Crosslinking is revealed by gel separation of tryptic peptides from core histones that carry 32P-labelled residual nucleotide. The ...

Histone gene expression is regulated in a cell cycle-dependent manner, with a peak at S phase, which is crucial for cell division and genome integrity. However, the detailed mechanisms by which expression of histone genes are tightly regulated remain largely unknown. Fission yeast Ams2, a GATA-type zinc finger motif-containing factor, is required for activation of S phase-specific core histone ...

Non-epithelial intermediate filament (IF) subunit proteins show a high and specific affinity for core histones at physiological ionic strength. When IF proteins are titrated with a mixture of core histones and linker histone H1, in general the latter is totally excluded from complexation and in the adducts formed the moderately-arginine-rich histones H2A and H2B are progressively replaced by th...