Aquaculture America 2020

February 9 - 12, 2020

Honolulu, Hawaii

HEAT SHOCK PROTEIN 70 GENE EXPRESSION AND STRESS RESPONSES OF RED-SPOTTED Epinephelus akaara AND HYBRID E. akaara FEMALE × E. lanceolatus MALE GROUPERS TO HEAT AND COLD SHOCK EXPOSURE

 
Youn Su Choa , Jung Yeol Parkb , Ji Hye Yoonb, Jong-Myoung Kima, Han Kyu Lim b,*
 a Department of Fishery biology
 Pukyong National University
Busan, 48512
 Republic of Korea
 b Department of Marine and Fisheries Resources
Mokpo National University
Jeonnam, 58554
 Republic of Korea
Limhk@mokpo.ac.kr
 

Temperature changes, such as those involved in heat and cold shocks , can induce heat shock protein 70 (HSP70) gene expression and stress responses in fish. This study observed the expression regulation of the HSP70 gene and the changes in plasma cortisol and glucose levels as a stress response in red-spotted (Epinephelus akaara) and hybrid (E. akaara female ×E. lanceolatus male) groupers during exposure to heat and cold shock. In red-spotted groupers, heat shock exposure did not induce upregulated expression of the HSP70 gene. This compares to  a seven-fold increase in HSP70 gene expression, but it did trigger gradual increases in plasma cortisol and glucose as a stress response in both  types of  groupers. During cold shock exposure, HSP70 expression in red-spotted groupers almost doubled, but it was lower than that of  the hybrid groupers . The hybrids exhibited gradual increases in HSP70 expression, nine times greater than that of  the control group . HSP70 expression patterns of hybrid groupers were completely reflective  of thermal stress responses of  the  fish. Although the effects of temperature stress on HSP70 expression in fish requires further study, the results of this study suggest that variations in HSP70 expression can serve as a sensitive biomarker of adaptation to temperature stress in specific fish.