Are viral small RNA regulating Dengue virus replication beyond serotype 2?

An article in PNAS by Hussain and Asgari (1) suggests that a viral small RNA (vsRNA) from the 3′ UTR of the Dengue virus (DENV) genome is important for the autoregulation of the viral replication in mosquito cells by acting as a microRNA (miRNA) targeting the NS1 region of the genome. The authors performed a sequence conservation analysis on the vsRNA-5 across the four serotypes. Unfortunately, the analysis was carried out using only one sequence from each serotype, which in the case of a genome segment from the variable region of the 3′ UTR may misrepresent the total virus diversity and, thus, its interpretation may be misleading. To better examine the vsRNA-5 conservation, the sequences provided in the article by Hussain and Asgari (1) were first mapped to their corresponding complete DENV genome, and all of the publicly available complete DENV genome sequences (n = 3,372) were aligned …