R2D2, a Bridge Between the Initiation and Effector Steps of the Drosophila RNAi Pathway
Qinghua Liu,1 Tim A. Rand,1 Savitha Kalidas,2 Fenghe Du,1 Hyun-Eui Kim,1 Dean P. Smith,2 Xiaodong Wang1*
The RNA interference (RNAi) pathway is initiated by processing long double-stranded RNA into small interfering RNA (siRNA). The siRNA-generating enzyme was purified from Drosophila S2cells and consists of two stoichiometric subunits: Dicer-2(DCR-2) and a previously unknown protein that we named R2D2. R2D2 is homologous to the Caenorhabditis elegans RNAi protein RDE-4. Association with R2D2 does not affect the enzymatic activity of DCR-2. Rather, the DCR-2/R2D2 complex, but not DCR-2 alone, binds to siRNA and enhances sequence-specific messenger RNA degradation mediated by the RNA-initiated silencing complex (RISC). These results indicate that R2D2 bridges the initiation and effector steps of the Drosophila RNAi pathway by facilitating siRNA passage from Dicer to RISC.
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R2D2, a Bridge Between the Initiation and Effector Steps of the Drosophila RNAi Pathway
Qinghua Liu, Tim A. Rand, Savitha Kalidas, Fenghe Du, Hyun-Eui Kim, Dean P. Smith, and Xiaodong Wang
Science Sep 26 2003: 1921-1925. [Abstract] [Full Text] [PDF] [Supporting Online Material]
