Comparative analysis on lung transcriptome of Mycoplasma ovipneumoniae (Mo) - infected Bashbay sheep and argali...

Bashbay sheep (Bbs) has a certain degree of resistance to Mycoplasma ovipneumoniae (Mo), however, Argali hybrid sheep (Ahs) is susceptible to Mo. To understand the molecular mechanisms underlying the difference of the susceptibility for Mo infection, RNA-sequencing technology was used to compare the transcriptomic response of the lung tissue of Mo-infected Bbs and Ahs.

Six Bbs and six Ahs were divided into experimental group and control group respectively, all of them were experimentally infected with Mo by intratracheal injection. For collecting lung tissue samples, three Bbs and three Ahs were sacrificed on day 4 post-infection, and the others were sacrificed on day 14 post-infection. Total RNA extracted from lung tissue were used for transcriptome analyses based on high-throughput sequencing technique and bioinformatics. The results showed that 212 (146 up-regulated, 66 down-regulated) DEGs were found when comparing transcriptomic data of Bbs and Ahs at 4th dpi, besides, 311 (158 up-regulated, 153 down-regulated) DEGs were found at 14th dpi. After GO analysis, three main GO items protein glycosylation, immune response and positive regulation of gene expression were found related to Mo infection. In addition, there were 20 DEGs enriched in these above items, such as SPLUC1 (BPIFA1), P2X7R, DQA, HO-1 and SP-A (SFTPA-1).

These selected 20 DEGs associated with Mo infection laid the foundation for further study on the underlying molecular mechanism involved in high level of resistance to Mo expressed by Bbs, meanwhile, provided deeper understandings about the development of pathogenicity and host-pathogen interactions.