Abstract

Bovine herpesvirus 1 (BoHV-1) infection extensively modulates host-cell gene expressions. To further understandings of BoHV-1 pathogenesis, Madin-Darby bovine kidney cells were infected, and RT-qPCR expression analyses were performed. Apart from classical immune genes (e.g. PKR, Mx1, IRF7, CCR4, TXNIP), EGR3, IFITM3, and ISG15 presented notably high transcripts. To gain further insight, the bovine ISG15 gene was characterized and compared against human, mouse, dog, fugu, salmon, and zebrafish homologues. In silico analysis revealed several conserved regions of interest, including a set of potential transcriptional motifs in the proximal 5’-untranslated region for all analyzed species. A protein-deduced bovine ISG15 sequence also evidenced many conserved domains in humans. Finally, in vitro infection assays with bovine viral diarrhea virus-1 or BoHV-1 both resulted in elevated blood ISG15 levels. Collectively, the obtained data indicate that ISG15 could potentially serve as an early immune marker during BoHV-1 and bovine viral diarrhea virus-1 infection.

Keywords: BoHV-1; BVDV-1; ISG15; Immune marker