Uptake of extracellular double-stranded RNA by SID-2.

ABSTRACT: Ingested dsRNAs trigger RNA interference (RNAi) in many invertebrates, including the nematode Caenorhabditis elegans. Here we show that the C. elegans apical intestinal membrane protein SID-2 is required in C. elegans for the import of ingested dsRNA and that, when expressed in Drosophila S2 cells, SID-2 enables the uptake of dsRNAs. SID-2-dependent dsRNA transport requires an acidic extracellular environment and is selective for dsRNAs with at least 50 base pairs. Through structure-function analysis, we identify several SID-2 regions required for this activity, including three extracellular, positively charged histidines. Finally, we find that SID-2-dependent transport is inhibited by drugs that interfere with vesicle transport. Therefore, we propose that environmental dsRNAs are imported

SUBMITTER: McEwan DL 

PROVIDER: S-EPMC3488460 | biostudies-literature | 2012 Sep

REPOSITORIES: biostudies-literature