Comparative analysis of heat tolerance and molecular adaptations in Venerupis aspera and Ruditapes philippinarum

Abstract

The impact of climate change on marine organisms is increasingly significant, highlighting the importance of understanding their heat tolerance mechanisms to predict and respond to future environmental changes. This study compares the physiological and molecular responses of the closely related clam species Venerupis aspera and Ruditapes philippinarum under heat stress conditions, revealing adaptive mechanisms of heat tolerance. Energy metabolism measurements and enzyme activity analyses revealed that V. aspera exhibits significantly higher heat tolerance than R. philippinarum in heat stress. V. aspera showed greater metabolic flexibility and elevated enzyme activities, enhancing physiological adaptability. Furthermore, in-depth transcriptomic analysis of the gene expression patterns under heat stress demonstrated that V. aspera up-regulated genes associated with heat shock proteins, antioxidant enzymes, and energy metabolism. In contrast, R. philippinarum exhibited fewer changes in the expression of these critical genes. This study provides original insights into the heat tolerance differences between V. aspera and R. philippinarum, elucidating their underlying molecular mechanisms. The dual regulation observed in V. aspera, achieved through metabolic adjustments and gene expression under heat stress conditions, contributes valuable knowledge to our understanding of biological adaptation to climate change. The findings have implications for marine ecological conservation strategies and resource management.