Neighbor-joining phylogenetic tree of double-stranded RNA-binding proteins. Major clusters of proteins include Staufen subfamilies (Stau1 and Stau2), HIV trans-activator RNA (TAR), RNA-binding protein (TRBP), protein kinase R (PKR)-activating protein (PACT), Loquacious and R2D2. Phylogenetic reconstruction method, species colour-coding and nodes labeling of significance are the same as Fig. 1. The multiple sequence alignment file is given in Additional file 4.