The distribution of high-mobility-group proteins in chromatin fractions produced by nuclease digestion of pig thymus nuclei

1981 ◽  
Vol 9 (1) ◽  
pp. 143-144
Author(s):  
MARK A. PLUMB ◽  
ALEXANDER J. MacGILLIVRAY
1980 ◽  
Vol 185 (1) ◽  
pp. 169-175 ◽  
Author(s):  
C T Teng ◽  
C S Teng

A non-histone chromosomal 95K protein (of mol.wt. 95 000) from hen oviduct was isolated and purified for antibody induction in the rabbit. Immuno-micro-complement-fixation and biochemical techniques were used to probe the presence of 95K protein in the oviduct chromatin of the embryonic and immature chick and the hen. The antiserum against 95K protein did not react with high-mobility-group proteins 1 and 2 obtained from oviduct, brain and liver, nor with histones. After limited digestion of chromatin with nucleases, until 10% DNA was hydrolysed, a small amount of 95K protein was released. Thus the 95K protein is probably not located in the region of chromatin that is sensitive to nuclease digestion. The amount of 95K protein in immature chick oviduct chromatin is less than that in the mature hen oviduct. However, the amount of 95K protein in the immature chick oviduct was increased after oestrogen administration. The presence of 95K protein in embryonic oviduct was detected in the 10-, 12-, 15- and 18- day chick embryo. The quantity of this protein increased with the age of the embryo and reached its highest value in the chromatin of the hen oviduct.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Stephanie Dobersch ◽  
Karla Rubio ◽  
Indrabahadur Singh ◽  
Stefan Günther ◽  
Johannes Graumann ◽  
...  

AbstractIn addition to nucleosomes, chromatin contains non-histone chromatin-associated proteins, of which the high-mobility group proteins are the most abundant. Chromatin-mediated regulation of transcription involves DNA methylation and histone modifications. However, the order of events and the precise function of high-mobility group proteins during transcription initiation remain unclear. Here we show that high-mobility group AT-hook 2 protein (HMGA2) induces DNA nicks at the transcription start site, which are required by the histone chaperone FACT complex to incorporate nucleosomes containing the histone variant H2A.X. Further, phosphorylation of H2A.X at S139 (γ-H2AX) is required for repair-mediated DNA demethylation and transcription activation. The relevance of these findings is demonstrated within the context of TGFB1 signaling and idiopathic pulmonary fibrosis, suggesting therapies against this lethal disease. Our data support the concept that chromatin opening during transcriptional initiation involves intermediates with DNA breaks that subsequently require DNA repair mechanisms to ensure genome integrity.


2008 ◽  
Vol 9 (1) ◽  
pp. 170-179 ◽  
Author(s):  
Donna R Louie ◽  
Kristen K. Gloor ◽  
Scott C. Galasinski ◽  
Katheryn A. Resing ◽  
Natalie G. Ahn

Biochemistry ◽  
1983 ◽  
Vol 22 (21) ◽  
pp. 5008-5015 ◽  
Author(s):  
Ronald L. Seale ◽  
Anthony T. Annunziato ◽  
Richard D. Smith

1984 ◽  
Vol 99 (2) ◽  
pp. 648-654 ◽  
Author(s):  
L Kuehl ◽  
B Salmond ◽  
L Tran

Nuclear and cytoplasmic fractions were isolated from various tissues of the rat by a nonaqueous technique. The high-mobility-group (HMG) proteins were extracted from these fractions with acid and separated by one- and two-dimensional PAGE. The concentrations of high-mobility-group proteins HMG1, HMG2, and HMG17 in the nucleus and cytoplasm were then estimated from the staining intensities of the electrophoretic bands. The cytoplasmic concentrations of these proteins were very low--usually less than 1/30 of those present in the corresponding nuclear fractions. For the tissues studied (liver, kidney, heart, and lung), the concentrations of HMG proteins in the nucleus did not differ significantly from one tissue to another. Averaged over the four tissues investigated, there were 0.28 molecule of HMG1, 0.18 molecule of HMG2, and 0.46 molecule of HMG17 per nucleosome. These values are considerably higher than those that have been reported previously.


Sign in / Sign up

Export Citation Format

Share Document