A Role for the RNase III Enzyme DCR-1 in RNA Interference and Germ Line Development in Caenorhabditis elegans

Abstract
An early event in RNA interference (RNAi) is the cleavage of the initiating double-stranded RNA (dsRNA) to short pieces, 21 to 23 nucleotides in length. Here we describe a null mutation indicer-1 (dcr-1), a gene proposed to encode the enzyme that generates these short RNAs. We find thatdcr-1(−/−) animals have defects in RNAi under some, but not all, conditions. Mutant animals have germ line defects that lead to sterility, suggesting that cleavage of dsRNA to short pieces is a requisite event in normal development.