Here, we report that EBV-encoded BART miRNAs target the 3'UTR of the LMP1 gene and negatively regulate LMP1 protein expression. These miRNAs also modulate LMP1-induced NF-kaapaB signaling and alleviate the cisplatin sensitivity of LMP1-expressing NPC cells
Lo and colleagues showed that three EBV miRNAs (miR-BART16, miR-BART17-5p, and miR-BART1-5p) target and downregulate LMP1 expression, thereby attenuating the pro-apoptotic affect of LMP1 and its inhibitory effect on NFkaapa-B. Thus, it appears that EBV miRNAs fine tune LMP1 expression in order to ensure cell survival.
In some cases, the target viral mRNA is regulated by multiple miRNAs. Several of the EBV BART miRNAs from a single genomic cluster(BART1-5p, BART3-5p, BART16, and BART17-5p) work together to down-regulate production of the EBV latency membrane protein 1(LMP1).
An overview of known targets of cellular or viral targets is given in tables 2 and 3.Table 2 Cellular Targets of viral miRNAs.Table 3 Viral Targets of viral miRNAs.