Does feulgen stain RNA?
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Does feulgen stain RNA?
RNA, where the purine linkage is acid-stable, did not react. Feulgen staining enabled nuclei to be clearly identified in animal and plant cells. The next step was to find a quantitative method for the estimation of the DNA in the nucleus. A suitable method for this was introduced by Caspersson (mid-1920s–ca.
What is feulgen stain used for?
Feulgen stain can visualize DNA on tissue sections and in cells. This staining is the most used staining to highlight DNA in histology. The principle of Feulgen stain is to dissociate the two strands of DNA through hydrolysis by a solution of molar HCl which destroys the purine bases.
Why feulgen stain is used in mitosis?
Feulgen stain provided excellent detail and morphology of mitotic cells and is best to demonstrate both apoptotic bodies and mitotic figures in comparison with H and E and crystal violet. Howeve, it is very technique sensitive, and the stain fades away within hours.
What is the reaction to feulgen stain?
The Feulgen reaction is based on Schiff’s reaction for aldehydes whereby, by acid hydrolysis, the liberated aldehydes of the deoxy sugar are allowed to react with fuchsin–sulphurous acid to yield a typical magenta colour reaction.
What is Feulgen test?
The Feulgen staining is a specific and sensitive method for evaluating DNA damages. It has been shown that using non-DNA specific stains to monitor nuclear anomalies lead to false-positive or false-negative results (7).
What is Feulgen positive and negative?
SUMMARY. The nuclei of the male and female gametocytes of the malarial parasites {Plasmo- dium and Hepatocystis) are Feulgen-negative, while the nuclei of the gametocytes of Hepatozoon, which are not sexually differentiated, are Feulgen-positive.
Why feulgen stain is used for DNA only?
The Feulgen technique selectively stains DNA, and under controlled conditions, can be used for the photometric determination of DNA content. The reaction consits of two steps. Fixed material is treated for 8-10 min with 1N HCl in a water bath or oven at 60°C.
Why is Feulgen DNA staining known as the semiquantitative method?
DNA should be stained red. The background, if counterstained, is green. The Feulgen reaction is a semi-quantitative technique. If the only aldehydes remaining in the cell are those produced from the hydrolysis of DNA, then the technique is quantitative for DNA.
Who have developed Feulgen technique?
The Feulgen procedure was invented by German physician and chemist Joachim Wilhelm Robert Feulgen during 1914-1924 [6, 7]. He also discovered animal and plant DNA (“thymonucleic acid”) congeniality and estimated the nature of nucleic acids as a polymers of nucleotides with four kinds of nitrogenous bases [11].
Why is RNA readily hydrolyzed by acid solutions as compared to DNA?
RNA is susceptible to this base-catalyzed hydrolysis because the ribose sugar in RNA has a hydroxyl group at the 2′ position. This feature makes RNA chemically unstable compared to DNA, which does not have this 2′ -OH group and thus is not susceptible to base-catalyzed hydrolysis.
What are the main components of Feulgen and Schiff’s reagent?
The Feulgen reaction consists of two steps. Initially, acid hydrolysis is performed, usually for 812 min, resulting in the cleavage of the nitrogen bases and formation of aldehyde groups. The preparations are then placed in light yellow Schiff reagent (fuchsine-sulfurous acid), which forms bonds with these groups.
Why feulgen staining is named so?
Feulgen stain is a staining technique discovered by Robert Feulgen and used in histology to identify chromosomal material or DNA in cell specimens. It is darkly stained.
What happens when RNA is hydrolyzed?
RNA hydrolysis is a reaction in which a phosphodiester bond in the sugar-phosphate backbone of RNA is broken, cleaving the RNA molecule. RNA is susceptible to this base-catalyzed hydrolysis because the ribose sugar in RNA has a hydroxyl group at the 2′ position.
Can RNA be hydrolyzed in acidic solution?
The phosphodiester bond of RNA is most stable at pH 4-5 at 90°C. RNA is susceptible to alkaline hydrolysis at pH > 6, whereas, in contrast, acid hydrolysis only occurs at pH < 2 [15].
What is the purpose of Schiff’s reagent?
Schiff’s reagent A reagent used for testing for aldehydes and ketones; it consists of a solution of fuchsin dye that has been decolorized by sulphur dioxide. Aliphatic aldehydes restore the pink immediately, whereas aromatic ketones have no effect on the reagent.
What products of hydrolysis did the RNA yield?
Solution : Complete hydrolysis of DNA (or RNA) yields a pentose sugar, phosphoric acid and nitrogen containing heterocyclic compounds (called bases).
What is the significance of pH in RNA extraction?
Results in total show that pH affects RNA interaction with a chitosan-based bioscaffold, and thus alters the concentration, purity, and integrity of isolated RNA, dependent on the method used.
