third double-stranded RNA binding motif of Drosophila melanogaster maternal effect protein Staufen and similar proteins
Staufen is a double-stranded RNA binding protein required both for the localization of maternal determinants to the posterior pole of the egg, oskar (osk) RNA, and for correct localization to the anterior pole, anchoring bicoid (bcd) RNA. The family also includes two Staufen homologs from vertebrates, Staufen 1 and Staufen 2. They are present in distinct ribonucleoprotein complexes and associate with different mRNAs. Staufen 1 may play a role in specific positioning of mRNAs at given sites in the cell by cross-linking cytoskeletal and RNA components, and in stimulating their translation at the site. It binds double-stranded RNA (regardless of the sequence) and tubulin. Staufen 2 is an RNA-binding protein required for the microtubule-dependent transport of neuronal RNA from the cell body to the dendrite. Staufen proteins contain five double-stranded RNA binding motifs (DSRMs). This model describes the third motif. DSRM is not sequence specific, but highly specific for dsRNAs of various origin and structure.
Jiyao W et al.(2023). "The conserved domain database in 2023.",