Heat shock protein 70 reflected the state of inhabited fish response to water quality within lake ecosystem.

Heat shock proteins are natural biomarker that plays a vital role in genetic variability and adaptive survival in organisms under environmental stress. We assessed the effect of the stressor using Heat shock protein 70 in Hemibarbus labeo and Lepomis macrochirus at three geological points of Juam and Yedang lake. The study focused on the stress-relieving effect of heat shock protein 70 expressed in fish associated with physicochemical factors in the lake ecosystem. We recorded significant upregulation (p < 0.05) of the heat shock protein 70 gene in L. macrochirus in Juam (0.99-fold) and Yedang (1.44-fold). The upregulation in H. labeo indicated 0.83-fold in Juam and 1.21-fold in Yedang. The water quality index determined using physicochemical factors was low in the middle regions of both lakes. However, the maximum gene expression distribution was found in Yedang. The two-way clustering analysis revealed ammonia, total phosphorus, and suspended solids with maximum stress threshold. Dissolved oxygen, pH, nitrate, and organic carbon were the stress factors with minimal concentrations induced expression. The key observations are (i) the vital influence of molecular markers regulated tolerance at initial stress levels, (ii) the synergistic effect of the stressors and Heat shock protein 70 induction impacted adaptive strategy in fishes to regain tolerance (iii) fish population (L. macrochirus) with elevated response exhibited maximum distribution, correlating with the practical scenario. Heat shock protein 70 expressions through metabolic compensation strategy thus influenced the size of inhabited fish population retarding biodiversity of the lake ecosystem. [ABSTRACT FROM AUTHOR]