Differential analysis of transcript levels of TLRs genes in the blood and lungs of different breeds of sheep

【Objective】 To analyze the variability of transcript levels of Toll-like receptors( TLRs ) genes in different breeds of sheep, and to provide a reference basis for revealing the association between the transcript levels of TLRs genes and epidemic diseases in sheep.【Method】 In this study, Guizhou black goat, Guizhou white goat, Qianbei Ma goat, Boer goat and Hu sheep, which are the main breeding species in Guizhou Province, were selected for the study, and fluorescent quantitative PCR specific amplification primers and TaqMan probe primers were designed according to the published TLRs gene sequences in GenBank, and the differences in transcript levels of TLR1-TLR10 genes in blood and lung of different breeds of sheep were detected by using TaqMan probe fluorescent quantitative PCR.【Result】 TLR1-TLR10 genes were transcriptionally expressed in the blood and lungs of different breeds of sheep. Differential transcript levels of TLRs genes were in both blood and lung of different breeds of sheep, the transcript levels of TLR2, TLR4 and TLR5 genes in the blood of Boer goats were extremely significantly lower than those of the other four species(P<0.01, the same below), the transcript levels of TLR7 and TLR8 genes were extremely significantly lower than those of the other three species of sheep except black goats. The transcript levels of TLR4, TLR7, TLR8 and TLR9 genes in the blood of white goats were extremely significantly higher than those of the other four species. The transcript levels of TLR2, TLR3, TLR4, TLR5 and TLR8 genes in the lungs of Hu sheep were extremely significantly lower than those of the other four sheep species, while the transcript levels of TLR5 and TLR8 genes were extremely highly significant higher in the lungs of Qianbei Ma sheep than in the other four species. In addition, the transcript levels of TLR2, TLR4, TLR7 and TLR8 genes in the blood of five sheep species were all extremely significantly higher than the transcript levels of other TLRs genes. Transcript levels of TLR2, TLR3, TLR4, TLR5 and TLR8 genes in sheep lungs were relatively high, in Guizhou white goat, Guizhou black goat and Boer goat all showed extremely significantly higher transcript levels than other TLRs genes.【Conclusion】 The transcript levels of TLRs genes in the blood and lungs of different breeds of sheep are different, with TLR2, TLR3, TLR4, TLR5 and TLR8 genes having relatively high transcript levels. It is suggested that TLRs play a role in the organism of different breeds of sheep in scavenging pathogens and maintaining the homeostasis of the organism, and the difference in the transcription level of TLRs genes may be one of the reasons for the difference in susceptibility of different breeds of sheep to epidemic diseases.