LncRNA and mRNA profiling during activation of tilapia macrophages by HSP70 and Streptococcus agalactiae antigen

Objectives: To investigate the IncRNA profiling during tilapia peritoneal macrophages (TPMs) activation and discuss the relationship between IncRNA and mRNA. Materials and Methods: RNA sequencing was used to investigate the IncRNA and mRNA profiles of TPMs activation following stimulation with Streptococcus agalactiae (Sa) antigen, heat shock protein 70 (HSP70) and HSP7O+Sa. The expressions of IncRNA and mRNA were confirmed by qPCR. 356 IncRNA, 10173 mRNA and 1782 transcripts of uncertain coding potential (TUCP) were differentially expressed by pairwise comparison. These IncRNAs were shorter in length, fewer in exon number and higher in expression levels as compared with mRNAs. 683 IncRNAs and 4320 mRNAs were co-located, while 316 IncRNAs and 9997 mRNAs were in co-expression networks. Seven mRNAs (ANKRD34A, FMODA, GJA3, CNTN5, BMP10, BAI2 and HS3ST6) were involved in both networks of LNC_00035 and LNC_000466. Differentially expressed genes were involved in signaling pathways, such as "phosphorylation", "cytokine-cytokine receptor interaction", "endocytosis" and "MHC protein complex". LNC_000792, LNC_000215, LNC_000035 and LNC_000310, with cis and/or trans relationships with mRNAs, were also involved in ceRNA network. Conclusions: These results might represent the first identified expression profile of IncRNAs and mRNAs in tilapia macrophages activated by HSP70 and Sa.