Tissue-Specific Variation in DNA and RNA Content of Disco Rani Fish Using Classical Colorimetric Methods
Ulka Aade *
Department of Zoology, Government of Maharashtra, Ismail Yusuf College of Arts, Science and Commerce, Jogeshwari (E), Mumbai-60, India.
Amranath Yadav
Department of Zoology, Government of Maharashtra, Ismail Yusuf College of Arts, Science and Commerce, Jogeshwari (E), Mumbai-60, India.
G. T. Kedar
Department of Zoology, Government of Maharashtra, Ismail Yusuf College of Arts, Science and Commerce, Jogeshwari (E), Mumbai-60, India.
Mohammed Shahid Shaikh
Department of Zoology, Government of Maharashtra, Ismail Yusuf College of Arts, Science and Commerce, Jogeshwari (E), Mumbai-60, India.
Rahil Shaikh
Department of Zoology, Government of Maharashtra, Ismail Yusuf College of Arts, Science and Commerce, Jogeshwari (E), Mumbai-60, India.
Shaheer Malik
Department of Zoology, Government of Maharashtra, Ismail Yusuf College of Arts, Science and Commerce, Jogeshwari (E), Mumbai-60, India.
*Author to whom correspondence should be addressed.
Abstract
Quantitative estimation of nucleic acids can provide comparative information on tissue composition and physiological activity. This study estimated DNA and RNA contents in the liver and gill tissues of Disco Rani fish (Priacanthus hamrur) using classical colorimetric procedures. DNA was measured using the diphenylamine method, whereas RNA was measured using the orcinol method. Absorbance was recorded with a colorimeter, and tissue concentrations were calculated from standard solutions. The estimated DNA concentration was higher in the liver (5.90 mg/ml) than in the gills (4.28 mg/ml). Conversely, RNA concentration was higher in the gills (7.40 mg/ml) than in the liver (5.80 mg/ml). The calculated RNA/DNA ratio was 0.98 in the liver and 1.73 in the gills, indicating greater RNA abundance relative to DNA in gill tissue under the experimental conditions. The DNA standard curve showed a progressive increase in absorbance with concentration, while the RNA standard curve displayed an overall increasing trend with minor deviations. These findings demonstrate descriptive tissue-specific differences in nucleic acid content. The higher DNA value in the liver may reflect differences in tissue architecture and cellular composition, whereas the higher RNA concentration and RNA/DNA ratio in the gills may be associated with their continuous physiological functions. The results remain preliminary because biological replication, inferential statistical analysis and molecular validation were not included.
Keywords: DNA estimation, RNA estimation, RNA/DNA ratio, diphenylamine method, orcinol method, liver tissue, gill tissue, Priacanthus hamrur, colorimetric analysis, fish physiology