Alternative polyadenylation events differ dramatically between Tongcheng and Large White pigs in response to PRRSV infection

Summary Alternative polyadenylation (APA) is a widespread post‐transcriptional regulation mechanism that increases the biological complexity of transcriptome and proteome. However, it is unclear whether APA regulation plays a role in genetic resistance to porcine reproductive and respiratory syndrome virus (PRRSV). Here, we reported genome‐wide APA regulation of porcine alveolar macrophages in PRRSV‐resistant Tongcheng (TC) pigs and PRRSV‐susceptible Large White (LW) pigs upon PRRSV infection. Using 3′ mRNA sequencing strategy, we detected 75 981 high‐quality APA sites in porcine alveolar macrophages of TC and LW pigs. Furthermore, 1202 and 1089 differentially expressed APA sites, as well as 79 and 117 untranslated region‐APA switching genes were identified in TC pigs and LW pigs upon PRRSV infection respectively. The APA events in TC pigs and LW pigs were involved in different biological pathways, while APA events in TC pigs are directly associated with the immune response to PRRSV infection. In addition, we identified genetic variations affecting polyadenylation signal between TC pigs and LW pigs. These findings would provide helpful information on APA regulation for further understanding of genetic resistance to PRRSV.