Viruses can interact with components of the nucleolus [48, 49] and viral proteins can co-localise with proteins such as nucleolin, B23 and fibrillarin (components of the nucleolus). The use of antifibrillarin antibodies identified NS4 in the nucleoli of cells harvested at 24 hours post-infection. Although NS4 was detected in the nucleoli late in infection, anti-fibrillarin antibodies failed to detect fibrillarin. This may reflect BTV induced apoptosis, leading to nuclear condensation and DNA fragmentation, blebbing of the plasma membrane and shrinkage [50, 51] , and/or host cell shut-off [4] . Similar findings were reported in rotavirus (another member of the family Reoviridae, genus Rotavirus) where NSP2 protein was found to cause depolymerisation of tubulin [52] .