Transcriptomic analysis of red-spotted grouper nervous necrosis virus infected Asian seabass Lates calcarifer (Bloch, 1790)

Abstract Red-spotted grouper nervous necrosis virus (RGNNV) has threatened aquaculture of the Asian seabass (Lates calcarifer) in many countries of the Asia-Pacific for decades. To understand the pathogenesis of RGNNV, a transcriptome analysis of the head kidney, a major fish lymphoid tissue which performs important immune functions and is involved in the hematopoiesis was undertaken. RNA from the head kidney of RGNNV infected fish was sequenced and compared RNA from uninfected control fish at two and 15-days post infection. Functional analysis revealed a number of differentially expressed genes implicated in autophagy (beclin-1 and inositol 1,4,5-trisphosphate receptor), superoxide production (cytochrome b-245 light chain, C3a anaphylatoxin chemotactic receptor and neutrophil cytosol factor 2-like), inflammation (leukocyte surface antigen CD53), antigen presentation (MHC class I alpha chain), antiviral activity (cholesterol 25-hydroxylase) and other immune functions (oxysterol-binding protein 1, dipeptidyl peptidase I, interleukin-5 receptor subunit alpha-like and tyrosine-protein kinase BTK). This is the first description of the change in L. calcarifer head kidney mRNA expression as a consequence of RGNNV infection and the information will serve as the rational basis for future investigations into the pathophysiology of NNV infection of fish.