scholarly journals A MICROPHOTOMETRIC STUDY OF THE SYNTHESES OF DESOXYRIBONUCLEIC ACID AND NUCLEAR HISTONE

1955 ◽  
Vol 1 (1) ◽  
pp. 17-28 ◽  
Author(s):  
David P. Bloch ◽  
Gabriel C. Godman
Keyword(s):  
Cell Division ◽  
Nucleic Acids ◽  
Standard Error ◽  
Basic Protein ◽  
Desoxyribonucleic Acid ◽  
Fast Green ◽  
Nuclear Histone ◽  
Source Of Error ◽  
Formalin Fixed

1. The fast green stain of Alfert and Geschwind for nuclear basic protein is shown to obey the Beer-Lambert laws when used on purified histone. Interference from acid substances other than nucleic acids as a possible source of error is indicated. 2. Use of this technique after a modified Feulgen stain enables determination of relative amounts of desoxyribonucleic acid and histone in the same individual cells. 3. DNA and histone are shown to have the same distribution in formalin-fixed nuclei. 4. The syntheses of DNA and histone proceed simultaneously resulting in the doubling of both these substances prior to cell division. 5. The standard error for histone values is greater than that for DNA; however, the source of this variability is not known.

scholarly journals A Histochemical Analysis of the Proteins in the Larval Fat Body of Sarcophaga Bullata

1966 ◽  
Vol 1 (1) ◽  
pp. 81-84
Author(s):  
KATHERINE A. BENSON ◽  
D. G. BENSON
Keyword(s):  
Nucleic Acids ◽  
Basic Protein ◽  
Fat Body ◽  
The Other ◽  
Acid Hydrolases ◽  
Histochemical Analysis ◽  
Fast Green ◽  
Sarcophaga Bullata ◽  
Control Procedures ◽  
Nuclear Histone

A comparison has been made between the basic proteins of the nucleus and the cytoplasm in the larval fat body cell of Sarcophaga bullata. Basic protein was found in four regions of the cell: in the nucleolus, in association with the DNA of the nucleus, as a diffuse reticulum extending throughout the cytoplasm, and as a complement of granules distributed throughout the cytoplasm. Of these four regions only the nucleolar basic protein was apparently unaffected by the blocking reactions of deamination and acetylation when stained with alkaline fast green. The proteins of the other regions were seen to be arginine-rich, but contained a sufficient amount of lysine to be slightly affected by control procedures. The cytoplasmic granular basic protein, lysosomal in nature, and the diffuse basic protein of the cytoplasm, RNA-associated, stained in exactly the same manner as did the nuclear histone with the three techniques used for histone demonstration and with the Sakaguchi reaction. Control procedures had no effect on the intensity of the Sakaguchi reaction in any region of the cell where arginine was demonstrable. It is suggested that the term histone be reserved for DNA-associated basic protein, and that some of the non-specificity of histone staining may be resolved by applying auxiliary methods for the demonstration of acid hydrolases or associated nucleic acids.

scholarly journals HISTOCHEMICALLY SELECTIVE ACIDOPHILIA OF BASIC NUCLEOPROTEINS IN CHROMATIN AND NUCLEOLI AT ALKALINE pH

1962 ◽  
Vol 10 (6) ◽  
pp. 691-703 ◽  
Author(s):  
S. S. SPICER
Keyword(s):  
Deoxyribonucleic Acid ◽  
Basic Protein ◽  
Acid Dye ◽  
Fast Green ◽  
Fixed Tissue ◽  
Formalin Fixed Tissue ◽  
Nuclear Structures ◽  
Ph Range ◽  
Fast Green Fcf ◽  
Formalin Fixed

Chromatin and nucleoli of tissues fixed with formalin-free, mercurial or alcoholic solutions, have the unique property of staining metachromatically with the acid dye Biebrich scarlet in the restricted pH range 9.0-10.0. The nuclear structures lack affinity for fast green FCF under these conditions so that a mixture of Biebrich scarlet and fast green stains chromatin and nucleoli a characteristic orange-red at pH 9.5. A Feulgen-Biebrich scarlet sequence distinguishes magenta DNA in chromatin and orange-red basic protein in nucleoli. Although nuclei in tissues fixed with the buffered mercurial show strong affinity for the basic dye alcian blue, nuclei in formalin-fixed tissue do not. In formalin-fixed, trichloroacetic acid (TCA)-extracted tissues, chromatin stains with Biebrich scarlet or fast green but nucleoli do not. The acidophilia induced by TCA may in part depend on the fact that deoxyribonucleic acid (DNA) is removed by this treatment. However such tissues lose the acidophilia of the chromatin when treated again with formaldehyde but regain the acidophilia after re-extraction with TCA, indicating removal of formaldehyde condensates from amines by TCA. The affinity of chromatin and nucleoli for Biebrich scarlet at pH 9.5 is highly susceptible to destruction by relatively brief nitrosation, acetylation or exposure to formaldehyde. Extraction with a sulfuric acid-mercurial reagent also eliminates this staining; but other solvents used for isolation of histone do not, except that 1 N HCl has such an effect when employed on sections of tissue fixed with HgCl2. After mild treatment with TCA, exposure to pH 9.5 buffer extracts DNA whereas buffer at pH 6.0 has no such effect.

Electron Microscopy of Nucleic Acids

1974 ◽  
Vol 32 ◽  
pp. 302-303
Author(s):  
Norman Davidson
Keyword(s):  
Electron Microscopy ◽  
Nucleic Acids ◽  
Basic Protein ◽  
Molecular Biologist ◽  
Topological Properties ◽  
Protein Film ◽  
Polynucleotide Chain

The basic protein film technique for mounting nucleic acids for electron microscopy has proven to be a general and powerful tool for the working molecular biologist in characterizing different nucleic acids. It i s possible to measure molecular lengths of duplex and single-stranded DNAs and RNAs. In particular, it is thus possible to as certain whether or not the nucleic acids extracted from a particular source are or are not homogeneous in length. The topological properties of the polynucleotide chain (linear or circular, relaxed or supercoiled circles, interlocked circles, etc. ) can also be as certained.

Programs for the Determination of the Coefficient and Standard Error of the Tetrachoric Correlation

1967 ◽  
Vol 27 (3) ◽  
pp. 723-727
Author(s):  
Steven G. Goldstein ◽  
James D. Linden ◽  
Thomas T. Baker
Keyword(s):  
Standard Error ◽  
Tetrachoric Correlation

A simple and rapid protocol for measuring the chitin content of Hermetia illucens (L.) (Diptera: Stratiomyidae) larvae

2020 ◽  
Vol 6 (3) ◽  
pp. 285-290 ◽  
Author(s):  
M.J. Woods ◽  
N.J. Goosen ◽  
L.C. Hoffman ◽  
E. Pieterse
Keyword(s):  
Nitrogen Content ◽  
Standard Error ◽  
Inorganic Compounds ◽  
Insect Larvae ◽  
Hermetia Illucens ◽  
Chitin Content ◽  
Chloroform Methanol ◽  
Hermetia Illucens Larvae ◽  
Inorganic Components

The study reports on a simple gravimetrical analysis to determine the chitin content of insect larvae. Hermetia illucens larvae, 16 days of age, was used as sample material. The method of analysis comprised of a defatting treatment by means of rapid solvent extraction (2:1 chloroform : methanol), followed by a treatment with 1 M HCL (demineralisation) and 1 M NaOH (deproteinisation). The nitrogen content of the obtained chitin was determined and compared to that of the nitrogen content of pure chitin (6.89). The chitin content of H. illucens larvae was determined to be 5.68±0.15% with a nitrogen content of 6.43±0.038 (mean ± standard error). The average nitrogen content of the isolated chitin was lower than the theoretical value calculated for pure chitin. This indicated that there was still a small amount of inorganic compounds present in the chitin of the insect larvae after applying the developed analytical procedures. This was confirmed by the ash value of the isolated chitin (1.50±0.06%) (mean ± standard error). The analysis is simple and accurate, which gives repeatable results, for the determination of the chitin content of H. illucens larvae. Further studies regarding the demineralisation treatment could improve the accuracy of the method due to the removal of all inorganic components. Future studies could also investigate the accuracy of the protocol on other insect species.

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