Roles of LncRNAs in Viral Infections

Liu, Weiwei; Ding, Chan

Recently, transcriptome analysis lncRNA ALT identified lncRNA ALT as an early lytic transcript and a splice isoform of LANA transcript in KSHV infection (Chandriani et al., 2010; Schifano et al., 2017) . The size of lncRNA ALT is large (approximately a ∼10,000-nucleotide transcript) and its abundance is very low. However, the specific role of lncRNA ALT remains unclear. β2.7 RNA, the most abundantly transcribed early gene from the HCMV genome in permissive cells, is a 2.7-kb unspliced polyadenylated lncRNA (Greenaway and Wilkinson, 1987; White and Spector, 2007) . Although, it also has some coding potential, β2.7 binds directly to the GRIM19 (genes associated with retinoid/IFN-induced mortality 19), a subunit of mitochondrial enzyme complex I, to protect virus-infected cells from apoptosis and results in continued ATP production, which is critical for the successful completion of the viral life cycle (Bergamini et al., 1998; Reeves et al., 2007) . Interaction of the β2.7 RNA with complex I inhibits rotenone stress-induced apoptosis in neuronal cells and this suggests that β2.7 RNA can be exploited in the development of a novel therapeutic for the treatment of Parkinson's disease (Kuan et al., 2012; Poole et al., 2016) . Moreover, β2.7 RNA can protect rat aortic endothelial cells from ischemia/reperfusion injury-induced apoptosis by reduction of reactive oxygen species (Zhao et al., 2010) .