Mitochondrial HSP70 cognate-mediated differential expression of JNK1/2 in the pollution stressed grey mullets, Mugil cephalus.

Cells have evolved different networks of cellular stress responses to adapt during environmental changes and survive combating wide variety of stress. Mitochondrial heat shock protein 70 (mtHSP70) are essential for maintaining cellular homeostasis. c-Jun-N terminal kinase (JNK), a subfamily of MAPK, plays a key role in the transmission of extracellular signal for survival and death. In the present investigation, the differential expression of phosphorylated JNK1/2 with corresponding increases in heat shock transcription factor-1 (HSF-1) under high levels of B-cell lymphoma 2 (Bcl-2), HSP70 transcripts (twofold) and mtHSP70 has been correlated with fish survival in polluted Ennore estuary. This study suggests that in Ennore sample, the amplification in HSP70 transcripts along with corresponding mtHSP70 overexpression might be due to activation of JNK1/2 and HSF-1. This would influence the expression of Bcl-2 protein involved in mitochondrial survival under pollution-stressed condition.