The selective extraction of histones from rye chromatin

1976 ◽  
Vol 54 (9) ◽  
pp. 765-771 ◽  
Author(s):  
Hélène LaRue ◽  
Dominick Pallotta
Keyword(s):  
Selective Extraction ◽  
Histone H1 ◽  
The Other ◽  
Calf Thymus

The selective extraction of histones from rye chromatin was studied using three different methods. Extractions with NaCl–phosphate buffers atpH 5.5 gave results similar to those already obtained with other types of chromatin. Histone H1 was selectively extracted with 0.6 M NaCl –0.001 M PO4, while the selectivity of dissociation of the other fractions was reduced at higher NaCl concentrations. The use of phosphate–urea buffers at pH 5.5 also revealed that the histones were dissociated at the same concentrations as were calf thymus histones. Histone H1 was extracted with 0.5 M PO4 – 1 M urea; H1, H2A, and H2B were extracted with 0.8 M PO4 – 2 M urea; and all histones were removed with 0.8 M PO4 –5.3 M urea. It was, however, observed that the dissociated rye histones H2A and H2B were unstable in these buffers. This instability was maximum in the presence of 3 M urea, where both histones were absent from the extracted proteins and the residual nucleoproteins. Finally, a solution of 30% ethanol −0.35 M NaCl – 6 M urea produced a rye nucleoprotein fraction containing only histone H1.

scholarly journals The binding of adenosine(5′)tetraphospho(5′)adenosine to calf thymus histones measured by non-equilibrium dialysis

1987 ◽  
Vol 246 (3) ◽  
pp. 681-686 ◽  
Author(s):  
G Just ◽  
E Holler
Keyword(s):  
Ionic Strength ◽  
Dissociation Constants ◽  
Equilibrium Dialysis ◽  
Physiological Saline ◽  
Histone H1 ◽  
The Other ◽  
Competition Assay ◽  
Calf Thymus ◽  
Non Equilibrium

Binding of adenosine(5′)tetraphospho(5′)adenosine (Ap4A) to histones of calf thymus was investigated by non-equilibrium dialysis. Histone H1 interacts with the dinucleotide via two strong sites and competes with Mg2+ ions. Intrinsic dissociation constants were 1.6 +/- 0.1 microM and 11 +/- 1 microM for zero and 0.4 mm-Mg2+ concentration respectively. Binding of poly(dT) and of other nucleotides to histone H1 was measured in an [3H]Ap4A-competition assay. The tendency to form complexes among nucleotides was highest for bisnucleoside tetraphosphates and decreased in the order poly(dT) greater than or equal to Ap4A approximately Gp4G greater than Ap4 much greater than Ap3A approximately Ap5A greater than or equal to ATP, GTP and dTTP. The co-ordination complex derived from Ap4A and cis-diammine-dichloroplatinum(II) was not reactive. The other histones of calf thymus also bound Ap4A with affinities decreasing in the order H4 approximately H3 greater than H1 greater than H2b greater than H2a. Ap4A stimulated the exchange of histone H1 between nucleosomes, but this effect was referred to ionic strength. It did not bind to assembled nucleosomes. Binding of Ap4A to histone H1 was decreased by salt (NaCl). At physiological saline concentration the value of the dissociation constant is commensurable with the value of the Ap4A concentration in the nucleus and thus indicative of complex-formation in vivo.

scholarly journals A method for the selective extraction of histone fractions f2(a)1 and f2(a)2 from calf thymus deoxyribonucleoprotein at pH7

1967 ◽  
Vol 105 (2) ◽  
pp. 611-614 ◽  
Author(s):  
E W Johns
Keyword(s):  
Acid Solution ◽  
Selective Extraction ◽  
New Method ◽  
Guanidinium Chloride ◽  
Histone Fraction ◽  
Acetone Precipitation ◽  
Calf Thymus

1. A new method has been developed for the specific extraction of histone fraction f2(a) from calf thymus deoxyribonucleoprotein at pH7 by using a mixture of ethanol and guanidinium chloride. 2. Fraction f2(a) has been separated into the subfractions f2(a)1 and f2(a)2 by acetone precipitation from acid solution, and at pH7. 3. Modifications of existing electrophoretic methods are described that enable these fractions to be more easily characterized.

ISOLATION AND CHARACTERIZATION OF RIBONUCLEIC ACID FROM RAT LENS

1962 ◽  
Vol 40 (1) ◽  
pp. 41-47 ◽  
Author(s):  
Anima Devi
Keyword(s):  
Amino Acids ◽  
The Other ◽  
Ocular Lens ◽  
E Coli ◽  
Isolation And Characterization ◽  
Coiled Structure ◽  
Calf Thymus ◽  
Original Procedure ◽  
Polynucleotide Chain

RNA from rat ocular lens has been isolated by a method based on Kirby's original procedure (7), but greatly modified so as to avoid any degradation of RNA by RNase during the process of its extraction from lenses. The absorption at 260 mμ of a 1.0% solution of this purified material in a 1-cm cell is 1.95. Its N/P ratio is 1.58. It has 20 to 25% activity of that of yeast-soluble RNA in accepting activated amino acids. When this RNA (like all other RNA's) is heated and cooled the polynucleotide chain can again form loops, thus suggesting a randomly coiled structure for this RNA. On the other hand, DNA preparations from calf thymus, rat liver, and E. coli showed irreversible changes when heated and cooled.

The topological trapping of circular DNAs on agarose: Unexpected restrictions on DNA rotation

1978 ◽  
Vol 56 (6) ◽  
pp. 585-591 ◽  
Author(s):  
Jeremy S. Lee ◽  
A. Richard Morgan
Keyword(s):  
Secondary Structure ◽  
Binding Constant ◽  
Binding Assay ◽  
Sodium Perchlorate ◽  
Binding Constants ◽  
The Other ◽  
Calf Thymus ◽  
Potential Applications ◽  
Open Circular ◽  
Circular Dnas

DNA linked to an insoluble matrix has many potential applications. In some cases, it is highly desirable that the DNA be chemically unaltered, and for this reason, we have developed methods for topologically trapping circular DNAs on agarose. Open circular (oc) DNA containing at least one nick is readily trapped on agarose which has been heated or dissolved in sodium perchlorate to destroy secondary structure and then gelled by cooling or dialysis respectively. On the other hand, covalently closed circular (ccc) DNA of superhelix density −0.12 (PM2 DNA) is only poorly trapped unless first relaxed by topoisomerases or with the appropriate addition of an intercalating drug. When the oc DNA – agarose was used in a procedure for rapidly obtaining binding constants of drugs to DNA, the binding constant of ethidium was found to be considerably less than that expected. On addition of calf thymus topoisomerase to the binding-assay mixture, the ethidium-binding constant increased to the expected value. Thus, although free oc DNA is topologically unrestricted, oc DNA trapped in agarose must be rotationally constrained such that addition of ethidium introduced supercoils. The nature of these constraints is discussed with respect to the known structure of agarose bihelices.

Kinetics of chemical modification of arginine and lysine residues in calf thymus histone H1

Biopolymers ◽  
1981 ◽  
Vol 20 (6) ◽  
pp. 1103-1112 ◽  
Author(s):  
Kazuei Mita ◽  
Sachiko Ichimura ◽  
Mitsuo Zama ◽  
Koei Hamana
Keyword(s):  
Chemical Modification ◽  
Histone H1 ◽  
Calf Thymus ◽  
Lysine Residues ◽  
Kinetics Of

scholarly journals Preparation and characterization of histone H1 from the sperm of the sea-urchin Sphaerechinus granularis

1981 ◽  
Vol 195 (1) ◽  
pp. 171-176 ◽  
Author(s):  
V Giancotti ◽  
S Cosimi ◽  
P D Cary ◽  
C Crane-Robinson ◽  
G Geraci
Keyword(s):  
Secondary Structure ◽  
Sea Urchin ◽  
Fluorescence Spectra ◽  
Tertiary Structure ◽  
Histone H1 ◽  
Separation And Purification ◽  
Tertiary Structures ◽  
Calf Thymus ◽  
Sea Urchin Sperm

The separation and purification of histone H1 from the sperm of the sea-urchin Sphaerechinus granularis is described. Physical studies were used to compare this histone H1 molecule with H1 histones from other species. C.d. and 270 MHz n.m.r. spectroscopy indicate that, despite significant compositional differences from other sea-urchin sperm H1 histones, their secondary and tertiary structures are very similar. A large difference in helicity was, however, found between S. granularis histone H1 and calf thymus histone H1, and their n.m.r. and fluorescence spectra also differ considerably. It is concluded that secondary structure and tertiary structure have not been conserved in the evolution of the H1 histone family.

Changes in binding affinity between ofloxacin and calf thymus DNA in the presence of histone H1: Spectroscopic and molecular modeling investigations

2018 ◽  
Vol 203 ◽  
pp. 599-608 ◽  
Author(s):  
Farzad Dehghani Sani ◽  
Niloufar Shakibapour ◽  
Sima Beigoli ◽  
Hamid Sadeghian ◽  
Maral Hosainzadeh ◽  
...  
Keyword(s):  
Molecular Modeling ◽  
Binding Affinity ◽  
Histone H1 ◽  
Calf Thymus Dna ◽  
Calf Thymus

Probing the binding of lomefloxacin to a calf thymus DNA-histone H1 complex by multi-spectroscopic and molecular modeling techniques

2018 ◽  
Vol 256 ◽  
pp. 127-138 ◽  
Author(s):  
Tahmineh Sohrabi ◽  
Maral Hosseinzadeh ◽  
Sima Beigoli ◽  
Mohammad Reza Saberi ◽  
Jamshidkhan Chamani
Keyword(s):  
Molecular Modeling ◽  
Histone H1 ◽  
Calf Thymus Dna ◽  
Calf Thymus ◽  
Modeling Techniques

Hyper(ADP-ribosyl)ation of histone H1

1982 ◽  
Vol 60 (12) ◽  
pp. 1085-1094 ◽  
Author(s):  
R. J. Aubin ◽  
V. T. Dam ◽  
J. Miclette ◽  
Y. Brousseau ◽  
A. Huletsky ◽  
...  
Keyword(s):  
Repeat Unit ◽  
Selective Extraction ◽  
Histone H1 ◽  
Polymerase Activity ◽  
Micrococcal Nuclease ◽  
Micrococcal Nuclease Digestion ◽  
Nuclease Digestion ◽  
Nonionic Detergent ◽  
Minimal Modification ◽  
Triton X

Nucleosomal chains of various repeat unit lengths were generated by a mild micrococcal nuclease digestion of purified pancreatic nuclei. Maximal nucleosome associated poly(ADP-ribose) polymerase activity was recovered in trimeric to tetrameric chromatin fragments, after which the enzyme activity gradually decreased and stabilized towards oligomeric periodicities of 11 to 16 nucleosomes. Electrophoresis of [32P] ADP-ribosylated histones on first-dimension acid–urea or acid–urea–Triton gels and on second-dimension acid – urea – cetyltriammonium bromide gels revealed that, of all histones, only histone H1 could be significantly poly(ADP-ribosyl)ated while only minimal modification could be recovered with histone H10. Furthermore, the extent of ADP-ribosylation present on pancreatic histone H1 is shown to proportionally retard this protein's electrophoretic mobility in all gel systems and to consist of a distinct series of at least 12 modification intermediates which can be evidenced, in nuclei or nucleosomes, and fully recovered along with histone H1 upon its selective extraction with 5% perchloric acid. The generation of these increasingly ADP-ribosylated forms of histone H1 is also demonstrated to be time dependent and the more complex ADP-ribosylated forms of this histone are favored at high NAD+ concentrations. Moreover, the electrophoretic mobilities of all intermediates are unaffected by the presence of the nonionic detergent Triton X-100.

The nucleolus

2019 ◽  
pp. 147-152
Author(s):  
John C. Lucchesi
Keyword(s):  
Gene Silencing ◽  
Histone H1 ◽  
Nucleolus Organizer ◽  
Linker Histone ◽  
The Other ◽  
Rrna Genes ◽  
Rrna Gene ◽  
Dna Repeats ◽  
Gene Arrays ◽  
Nucleolus Organizer Regions

The nucleolus forms at nucleolus organizer regions (NORs) that consist of clusters of repeated rRNA genes. Transcription of the rRNA genes and processing of the transcripts yields the three types of RNAs necessary for the biogenesis of ribosomes. Only subsets of the rRNA genes present in cells are transcribed. The linker histone H1 plays a specific role in the repression of inactive rRNA genes and in many of the other functions of the nucleolus. One of these functions is gene silencing—the nucleolus is surrounded by a zone of heterochromatin consisting of silenced rRNA gene arrays, DNA repeats that flank the centromeres and chromatin domains that include gene-poor, as well as silent, regions of the genome; any gene associating with this zone is subjected to repression. Other functions include the assembly of telomerase, the regulation of p53 stability and the synthesis of 5S and tRNAs whose genes form clusters in the nucleolus.

Sign in / Sign up

Export Citation Format

Share Document