The latency-related gene encoded by bovine herpesvirus 1 can suppress caspase 3 and caspase 9 cleavage during productive infection.

When the bovine herpesvirus 1 (BHV-1) latency-related (LR) gene is inserted into the latency-associated transcript (LAT) locus of a herpes simplex virus type 1 (HSV-1) LAT deletion mutant, high levels of spontaneous reactivation from latency and enhanced pathogenesis occur. The LR gene, but not LAT, inhibits caspase 3 cleavage during productive infection. Plasmids containing LAT or the LR gene inhibit caspase 3 activation in transiently transfected cells, suggesting productive infection blocks certain antiapoptotic properties of LAT. These studies demonstrate a correlation between the enhanced pathogenic potential of CJLAT and the LR gene inhibiting caspase 3 cleavage during productive infection.