Transcriptome Analysis of mRNA and miRNA in Adherent Intestinal Cells of Atlantic Salmon, Salmo salar
Head kidney (HK) and distal intestine (DI) from Atlantic salmon (average 550g) were collected. Immune cells from DI and HK were extracted and grown at 12°C in Leibovitz's L-15 Medium (L-15). The isolated DI or HK leukocytes were allowed to adhere on a petri dish with 2 mL L-15+ for 2 days at 12°C. After removing the supernatant containing non-adherent cells, the adherent cells on petri dish were detached by washing three times with 1.5 mL ice-cold PBS supplemented with 5 mM EDTA. The cells were centrifuged (500 × g, 5 min, 4°C) and re-suspended with 2 mL L-15+. Total RNA was extracted from adherent cells from HK or DI (< 500,000 cells). To understand the miRNA expression profiles of adherent intestinal cells (AICs) and to compare them with those of adherent head kidney cells (AKCs), twelve libraries (6 for AIC and 6 for AKC) were prepared. Small RNA-sequencing revealed 37 differentially expressed miRNAs; 20 were up-regulated and 17 were down-regulated. Of them, 12 miRNAs in AIC were found to be involved in regulating macrophage functions. Overall design: Twelve samples were prepared including 6 from distal intestine and 6 from head kidney.