Effect of heat shock protein 70 polymorphism on thermotolerance in Tharparkar cattle

Abstract

Aim:Out of various members of heat shock protein (HSP) superfamily which act a molecular chaperon by binding to the denaturing protein thus stabilizing them and preserving their activity, HSP70 are of major importance in thermotolerance development. Thus, present investigation aimed at a screening of HSP70 gene for polymorphisms and possible differences in thermotolerance in Tharparkar breed of cattle.Materials and Methods:A 295 bp fragment of HSP70 gene was subjected to polymerase chain reaction-single-strand conformation polymorphism (SSCP) followed by sequencing of different SSCP patterns in 64 Tharparkar cattle. A comparative thermotolerance of identified genotypes was analyzed using heat tolerance coefficients (HTCs) of animals for different seasons.Results:Three SSCP patterns and consequently two alleles namely A and B were documented in one fragment of HSP70 gene. On sequencing, one single-nucleotide polymorphism with G > T substitution was found at a position that led to a change of amino acid aspartate to tyrosine in allele A. It was found that in maintaining near normal average rectal temperature, genotype AA was superior (p≤0.01). Genotype AA, thus, was found to be most thermotolerant genotype with the highest HTC (p≤0.01).Conclusion:The polymorphism at HSP70 is expected to be a potent determinant for heat tolerance in cattle, which may aid in selection for thermotolerance in cattle.

Heat shock protein 70 from a thermotolerant Diptera species provides higher thermoresistance to Drosophila larvae than correspondent endogenous gene

“…hsp70 genes from D. melanogaster and S. singularior exhibit only 85% identity, and some of the observed differences in the sequence may have adaptive value. Previously, it was demonstrated in several organisms that polymorphism in the hsp70 gene itself can be a determinant of a species' heat tolerance (Bhat et al, 2016;Papot et al, 2016).…”

“…We speculated that the high thermotolerance of S. singularior species may be at least partially determined by the specific composition and functional characteristics of Hsp70, which, along with the high constitutive content of Hsp70, may provide this species with the ability to tolerate extreme habitats. Along these lines, accumulating data from other organisms suggest that genetic polymorphism in the regulatory and/or coding regions of hsp70 may be associated with high tolerance to heat and other environmental challenges (Bettencourt et al, 1999;Bettencourt & Feder, 2001Bhat et al, 2016). These studies suggest that the hsp70 genes of organisms from thermally contrasting niches are under stringent evolutionary constraints, and that these constraints may modify the structure of these genes to enhance the chaperone capacities of hsps within the cell and provide normal functioning under extreme environmental conditions (Garbuz et al, 2011;Qi et al, 2014;Papot et al, 2016).…”

Role of Heat Shock Proteins in Livestock Adaptation to Heat Stress

“…23,30 The function of HSP70 as a molecular chaperone and cell protection against HS capable of denaturing proteins has been studied through extensive research. 31 Several studies have been done to identify genetic polymorphism in HSP70 genes of cattle. The HSPs provide protection against the adverse effects of heat and chemical or abnormal stresses.…”

“…51 Cytoprotective function of HSP70 has been established in many organs such as intestine, kidney and embryo of cattle. 31 The HSP70 is one of the most abundant HSP family playing a crucial role in environmental stress and thermal adaptation in goat. 42,52 Increased expression of many HSPs including HSP32, HSP40, HSP60, HSP70, HSP90, HSP110 and many others are also observed in goat during hyperthermic stress.…”

“…51 Cytoprotective function of HSP70 has been established in many organs such as intestine, kidney and embryo of cattle. 31 The HSP70 is one of the most abundant HSP family playing a crucial role in environmental stress and thermal adaptation in goat. …”