Abstract

The Middle East respiratory syndrome Coronavirus (MERS-CoV) is a novel human coronavirus causing respiratory syndrome since April 2012 [1]. The replication of MERS-CoV is mediated by Orf 1ab and viral gene activity can be modulated by RNAi approach. The main objective of this work to evaluate the antiviral activity of siRNAs in cell culture. To design the siRNAs, we have selected orf1ab gene of MERS-CoV genome and used online software [2]. The designed siRNAs were chemically synthesized commercially by IDT. The antiviral activity of six siRNAs were evaluated and presented in this study at various concentrations (0.2-100nm) in Vero cells. In this study, total of twenty-one potential, functional, off-target reduced siRNA were Insilico designed, selected and chemically synthesized. The antiviral activity of siRNAs was evaluated by Realtime PCR. The CT value of all six siRNAs were obtained from both supernatant and cell lysate. The siRNA-3 and siRNA-4 were observed to be better antiviral activity as compared to control sample. Based on results obtained in this study, it is concluded that the selection protocols, accuracy and strength of designed siRNA are very helpful to minimize the possible cytotoxic effects of siRNA in Vero cells. The selected siRNAs provided promising results that make them good candidates for further evaluation of their anti- MERS-CoV activity in another cell line. The results obtained from this study are very helpful to evaluate the remaining siRNAs in other cell cultures and further to study their inhibition of virus replication in multiple cell cultures.