Profiles and biological analysis of lncRNAs in RAW264.7 macrophages infected by space mutagenized Escherichia coli after simulated microgravity

Objective To explore the difference expression of long non‐coding RNAs(LncRNAs) of RAW264.7 macrophages infected by space mutagenized Escherichia coli(E.coli) after simulated microgravity. Methods RAW264.7 macrophages were randomly divided into four groups. G1 and G2 were cultured in normal gravity for 72 hours. G3 and G4 were cultured in simulated microgravity for 72 hours, then G2 and G4 were infected for 6 hours by space mutagenized E.coli in Shenzhou 10 spacecraft, G1 and G3 were cultured for 6 hours in normal culture media. Total RNA was extracted from the cells in four groups. The profile of lncRNAs were detected with SBC‐lncRNA chips and the significant difference expression of lncRNAs were screened (fold change≥2; P≤0.05). The significant signaling pathways were enriched from the different expression of gene in G2 vs G2 and G4 vs G1. The Pathway‐Network was constructed based on the pathways with significant differences to get the key signaling pathway. The gene network graph was constructed based on the expression values of G2 and G4 to screen the key genes in the coexpression network. Results Differently expressed lncRNAs were detected as follows(fold change≥2, P≤0.05): there were 5843 lncRNAs detected totally in G2 vs G1, in which there were 2140 up‐regulated lncRNAs and 3703 down‐regulated lncRNAs. G4 vs G1 detected totally 7187 lncRNAs, in which 3230 lncRNAs were up‐regulated and 3957 lncRNAs were down‐regulated. G4 vs G2 detected totally 31 lncRNAs, in which there were 27 up‐regulated and 4 down‐regulated lncRNAs. The Csf3, Ripk2, A130077B15Rik were recognized as key genes in coexpression network. The most different expression gene was Csf3, which only existed in G2 but not existed in G4, and related with PI3K‐Akt signaling pathway, Cytokine‐Cytokine receptor interaction and Jak‐STAT signaling pathway. Ripk2 is related with immunologic function and can induce cell apoptosis by activating the NF kB signaling pathway. A130077B15Rik, as a LncRNA, might be associated with immunity and inflammation. Conclusion Our work explored the difference expression of LncRNAs in RAW264.7 macrophages infected by space mutagenized E. coli after simulated microgravity, which established the basis for the research of LncRNAs mechanisms of bacterial pathogenicity in spaceflight. Support or Funding Information Funded by National Basic Research Programs of China, No.2014CB744404