A SNP in the HSP90AA1 gene 5′ flanking region is associated with the adaptation to differential thermal conditions in the ovine species

Abstract

Molecular chaperones have long been understood to be preferentially transcribed in response to multiple perturbations of the cellular homeostasis. In this study, several polymorphisms in the gene encoding the inducible form of the cytoplasmic Hsp90 (HSP90AA1) were addressed in 24 sheep breeds reared in different climatic regions of Europe, Africa, and Asia. Significant differences in the genotype frequencies for a C/G single nucleotide polymorphism (SNP) located at position -660 in the HSP90AA1 5'flanking region were found between the different breeds. Regression analyses reflected significant correlations (from 0.41 to 0.62) between the alternative genotypes of this polymorphism and several climatic and geographic variables characteristic of the regions where these breeds are reared. Real-time analysis revealed that animals bearing the CC(-660) genotype presented higher expression levels than those presenting the CG(-660) or GG(-660) in summer, but not in spring. Mutation at -660 site seems to affect HSP90AA1 transcription rates which could have important effects on the adaptation to different environmental conditions in sheep. Thus, the variability found in the genotype frequencies for the SNP at -660 in the ovine HSP90AA1 locus could be the result of the different environmental pressures occurring in the regions where these breed are maintained.

Polymorphisms at the 5′ flanking region of the HSP90AA1 gene in native Turkish sheep breeds

“…In this study, as breeds are located in a more restricted geographic area (different locations in Turkey), with less climatic differences, the results are not as evident as in the study developed by Marcos-Carcavilla et al (2010b). Differences observed between breeds demonstrated the existence of a northsouth division that might be due to historic causes, such as different ancestors from which north and south populations were originated.…”

“…A 300 bp region of the 5 0 flanking region of the HSP90AA1 gene was amplified as previously described by Marcos-Carcavilla et al (2010b). The resulting PCR fragments were purified with a Macherey-Nagel Extract II purification kit (GmbH & Co., KG) and sequenced with specific primers, also reported by Marcos-Carcavilla et al (2010b).…”

Polymorphisms in the HSP90AA1 5′ flanking region are associated with scrapie incubation period in sheep

“…Interestingly, in a parallel study (Marcos-Carcavilla et al 2009) performed on ARR/ARR Manchega sheep breed, it has been observed that after several days of high temperatures, HSP90AA1 expression increased significantly (p< 0.05) in animals bearing the CC −660 AA −528 genotype. Conversely, no significant differences were detected in their CG −660 AG −528 counterparts.…”

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

“…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.…”