Ovine HSP90AA1 Expression Rate Is Affected by Several SNPs at the Promoter under Both Basal and Heat Stress Conditions

Abstract

The aim of this work was to investigate the association between polymorphisms located at the HSP90AA1 ovine gene promoter and gene expression rate under different environmental conditions, using a mixed model approach. Blood samples from 120 unrelated rams of the Manchega sheep breed were collected at three time points differing in environmental conditions. Rams were selected on the basis of their genotype for the transversion G/C located 660 base pairs upstream the gene transcription initiation site. Animals were also genotyped for another set of 6 SNPs located at the gene promoter. Two SNPs, G/C−660 and A/G−444, were associated with gene overexpression resulting from heat stress. The composed genotype CC−660-AG−444 was the genotype having the highest expression rates with fold changes ranging from 2.2 to 3.0. The genotype AG−522 showed the highest expression levels under control conditions with a fold change of 1.4. Under these conditions, the composed genotype CC−601-TT−524-AG−522-TT−468 is expected to be correlated with higher basal expression of the gene according to genotype frequencies and linkage disequilibrium values. Some putative transcription factors were predicted for binding sites where the SNPs considered are located. Since the expression rate of the gene under alternative environmental conditions seems to depend on the composed genotype of several SNPs located at its promoter, a cooperative regulation of the transcription of the HSP90AA1 gene could be hypothesized. Nevertheless epigenetic regulation mechanisms cannot be discarded.

Promoter variants at AP2 box region of Hsp70.1 affect thermal stress response and milk production traits in Frieswal cross bred cattle

“…Earlier several studies reported the association of SNP in Hsp to respiration rate and body temperature of cattle under stress to ascertain relative thermal tolerance (Charoensook et al, 2012;Liu et al, 2011). Similarly adaptation to different thermal conditions was associated with the specific SNP of Hsp90 in ovine species (Salces et al, 2013). An increased respiration rate is an important thermoregulatory response to heat stress in animals.…”

In silico analysis of regulatory and structural motifs of the ovine HSP90AA1 gene

“…This dual behavior could explain the fact that the HSP90AA1 gene is more inducible than its constitutive counterpart, the HSP90AB1, which has non-canonical core promoter elements associated with a 5′ end CGI (ENSOARG00000009343). In fact, HSP90AB1 is more stable under thermo-neutral and heat stress conditions than HSP90AA1 and several commercial HK tested in previous works of our group (Salces-Ortiz et al 2013;Serrano et al 2011).…”

“…Polymerase chain reaction was performed and the resulting PCR fragments were sequenced as in Salces-Ortiz et al (2013). A promoter fragment of 499 bp was obtained, containing 11 polymorphisms (Salces-Ortiz et al 2015c).…”

“…Hsp90α is necessary for spermatogenesis and meiotic progression in mammalian testis (Grad et al 2010). The ovine HSP90AA1 gene has been studied thoroughly by our group since 2008 (Marcos-Carcavilla et al 2008, 2010aOner et al 2012;Salces-Ortiz et al 2013, 2015a. A recent functional analysis of the ovine HSP90AA1 gene (Salces-Ortiz et al 2015c) has demonstrated that two linked polymorphisms, a cytosine insertion (g.667_668insC; rs397514115) and a C to G transversion (g.660G>C; rs397514116), both located at the promoter region, are mainly responsible for the observed differences in the expression rate of the gene in response to heat stress events.…”

Role of Heat Shock Proteins in Livestock Adaptation to Heat Stress

“…[45][46][47][48] In farm animals, elevation in HSP70 and HSP90 was observed in sheep, buffalo, cattle, broilers and goats. 11,49,50 The highest level of plasma HSP70 and PBMC HSP70 mRNA transcript expression was reported in Osamanabadi goats exposed to heat and nutritional stress as compared to the control goat which was maintained in the shed and fed ad libitum.…”