Transcriptome analysis reveals corresponding genes and key pathways involved in heat stress in Hu sheep
Heat stress (HS) seriously affects animal performance. In view of global warming, it is essential to understand the regulatory mechanisms by which animals adapt to heat stress. In this study, our aim was to explore the genes and pathways involved in heat stress in sheep. To this end, we used transcriptome analysis to understand the molecular responses to heat stress and thereby identify means to protect sheep from heat shock. To obtain an overview of the effects of heat stress on sheep, we used the hypothalamus for transcriptome sequencing and identified differentially expressed genes (DEGs; false discovery rate (FDR) < 0.01; fold change > 2) during heat stress. A total of 1423 DEGs (1122 upregulated and 301 downregulated) were identified and classified into Gene Ontology (GO) categories and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Heat stress triggered dramatic and complex alterations in gene expression in the hypothalamus. We hypothesized that heat stress induced apoptosis and dysfunction in cells and vital organs and affected growth, development, reproduction, and circadian entrainment via the calcium signaling pathway, which influences ribosome assembly and function. Real-time PCR was used to evaluate the expression of the genes regulating important biological functions or whose expression profiles were significantly changed after acute heat stress (FDR < 0.01; fold change > 4), and the results showed that the expression patterns of these genes were consistent with the results of transcriptome sequencing, indicating that the credibility of the sequencing results. Our data indicated that heat stress induced calcium dyshomeostasis, blocked biogenesis, caused ROS accumulation, impaired the antioxidant system and innate defense, and induced apoptosis through the P53 signaling pathway activated by PEG3, decreased growth and development, and enhanced organ damage. These data is very important and helpful to elucidate the molecular mechanism of heat stress and finally to find ways to deal with heat stress damage in sheep.
KeywordsHu sheep Heat stress Transcriptome sequencing GO annotation KEGG pathway
differentially expressed gene
false discovery rate
fragments per kilobase of transcript per million fragment mapped
Kyoto Encyclopedia of Genes and Genomes
reactive oxygen species
This study was supported by Jiangsu Agricultural Science and Technology Innovation Fund (CX (18)3004), the Jiangsu Provincial Department of Science and Technology key platform Projects (JSGB2018-08), and Natural Science Foundation of Jiangsu Province (BK20161377).
Compliance with ethical standards
Conflict of interest
The authors declare that they have no competing interests.
The use of the animals was in agreement with the Committee on Ethics of Animal Experimentation from the Jiangsu Academy of Agricultural Sciences. The experiment was performed according to regulations and guidelines established by this committee.
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