LZTR1 and infection: Following infection of BSR cells with BTV1 at an MOI of 5, viral protein expression was analyzed by immunofluorescence assays from 4 h.p.i to 10 h.p.i, using NS2 as the VIB marker, the inner capsid VP6, the helicase/RNA packaging protein, and the outer capsid protein VP5 (Figure 1a).