Nantapojd T.Panyim S.Ongvarrasopone C.Mahidol University2023-06-182023-06-182022-01-15Aquaculture Vol.546 (2022)00448486https://repository.li.mahidol.ac.th/handle/123456789/83342Disease especially caused by White spot syndrome virus (WSSV) has a huge impact on the shrimp production industry. An understanding of shrimp-WSSV interaction could lead to an effective approach to control WSSV infection. MicroRNA (miRNA) is a short small RNA which functions in post-transcriptional gene regulation and is involved in the WSSV infection. Previously, WSSV-encoded miRNAs were identified from infected P. monodon. We investigated wsv-miR-9 which showed the highest expression in WSSV-infected gill tissue. The expression of wsv-miR-9 was up-regulated upon WSSV infection and reduced in moribund shrimp. Antisense inhibition using anti-miRNA oligonucleotides (AMO) resulted in a complete inhibition of wsv-miR-9 expression. An in vitro functional study demonstrated that mimic of wsv-miR-9 could function in translational suppression by decreasing the reporter protein activity when compared to the mutant target. In shrimp, loss of wsv-miR-9 by AMO9 resulted in a delay of viral replication after 6–12 h post WSSV challenge. A reduction of WSSV early genes, ie1 and DNA polymerase mRNA expressions was observed within 6 h. These results reveal that wsv-miR-9 is important in maintaining early viral gene expression.Agricultural and Biological SciencesWhite spot syndrome virus-encoded microRNA promotes viral replication by maintaining viral early gene expressionArticleSCOPUS10.1016/j.aquaculture.2021.7372842-s2.0-85111818859