Viral lncRNA: A regulatory molecule for controlling virus life cycle

Wang, Ziqiang; Zhao, Yiwan; Zhang, Yaou

For DNA viruses, polyadenylated nuclear (PAN) RNA, which is a lncRNA encoded by the Kaposi's sarcoma-associated herpesvirus (KSHV) genome, can transcriptionally activate KSHV gene expression by physically interacting with the KSHV genome [7] . Alternatively, PAN RNA can relieve gene suppression by acting as a molecular scaffold for chromatin modifying enzymes to remove the H3K27me3 mark [8] , which is required for the production of late viral proteins, by binding to the host poly(A)-binding protein C1 (PABPC1) to regulate mRNA stability and translation efficiency [9] . Moreover, adenovirus virus-associated RNA (VARNA) I is involved in the selective translation of viral mRNA and the shut-off of host cell protein synthesis by inhibiting the cleavage of double-stranded RNA and the inactivation of DAI, which is an eIF-2 kinase known to be a suppressor of protein translation initiation [10, 11] . In addition to lncRNAs encoded by viral genomes, NEAT1 (nuclear enriched abundant transcript 1) is a cellular lncRNA that functions as a scaffold for paraspeckle formation [12e14] and is induced by viral infection [15e17] . Recently, we found that NEAT1 binds to viral genes and increases viral gene expression and viral replication [18] .