RNA silencing of rotavirus gene expression.

RNA interference (RNAi) is a double-stranded RNA (dsRNA)-triggered mechanism for suppressing gene expression, which is conserved in evolution and has emerged as a powerful tool to study gene function. Rotaviruses, the leading cause of severe diarrhea in young children, are formed by three concentric layers of protein, and a genome composed of 11 segments of dsRNA. Here, we show that the RNAi machinery can be triggered to silence rotavirus gene expression by sequence-specific short interfering RNAs (siRNAs). RNAi is also useful for the study of the virus-cell interactions, through the silencing of cellular genes that are potentially important for the replication of the virus. Interestingly, while the translation of mRNAs is readily stopped by the RNAi machinery, the viral transcripts involved in virus genome replication do not seem to be susceptible to RNAi. Since gene silencing by RNAi is very efficient and specific, this system could become a novel therapeutic approach for rotavirus and other virus infections, once efficient methods for in vivo delivery of siRNAs are developed. Although the use of RNAi as an antiviral therapeutic tool remains to be demonstrated, there is no doubt that this technology will influence drastically the way postgenomic virus research is conducted.