Role of Heat Shock Proteins in Livestock Adaptation to Heat Stress

The present review is an attempt to signify the importance of heat shock proteins in livestock adaptation during heat stress. The cellular and molecular responses in livestock are very crucial as it may lead to identification of confirmatory biomarker for heat stress in livestock. Thermo-tolerant gene expression and elevated heat shock protein (HSP) levels are observed to be the ultimate response through which the cell survives the heat stress. The HSPs have chaperonic activity ensuring the folding, unfolding and refolding of stress-denatured proteins. The components of heat shock response include heat shock factors (HSFs), heat shock element (HSE) and HSP. The cellular response to heat stress in mammalian organisms is controlled at the transcription level and it is mediated by a family of HSF which are regulated by the corresponding HSF genes. The activated HSFs bind with the HSE in the promoter region of HSP genes culminating in enhanced transcription of HSP mRNA. The HSP70, HSP90 and HSP27 are the predominant HSPs having protective role during heat stress in farm animals. Among these HSPs studied, HSP70 was identified to be the ideal biological marker for quantifying heat stress in animals.