Multiple alignment of CRV-ZWE-157, RISC-loading complex subunit TRBP2 [PDB:3ADL] , DGCR8 [PDB:1X47] , and Staufen RNA binding homolog [PDB:1UHZ] . Upper panel: Only the predicted dsRNA-binding region of CRV-ZWE-157 and the known dsRNA-binding regions of the other proteins are shown. Asterisks show amino acids crucial for dsRNA binding, dots indicate other perfectly conserved residues. Lower panel: Red bars represent α helices and green arrows represent β strands; these are aligned with the amino acid sequences above. The ksdssp algorithm was used to determine the secondary structures from the 3D structures or models.