| Type: | Domain | Name: | OST-HTH/LOTUS domain |
| Description: | This predicted RNA-binding domain found in insect Oskar and vertebrate TDRD5/TDRD7 proteins that nucleate or organise structurally related ribonucleoprotein (RNP) complexes, the polar granule and nuage, is poorly understood [, ]. The domain adopts the winged helix-turn-helix fold and binds RNA with a potential specificity for dsRNA []. In eukaryotes, this domain is often combined in the same polypeptide with protein-protein- or lipid- interaction domains that might play a role in anchoring these proteins to specific cytoskeletal structures. Thus, proteins with this domain might have a key role in the recognition and localisation of dsRNA, including miRNAs, rasiRNAs and piRNAs hybridized to their targets. In other cases, this domain is fused to ubiquitin-binding, E3 ligase and ubiquitin-like domains, indicating a previously under-appreciated role for ubiquitination in regulating the assembly and stability of nuage-like RNP complexes. Both bacteria and eukaryotes encode a conserved family of proteins that combines this predicted RNA-binding domain with a previously uncharacterised RNAse domain belonging to the superfamily that includes the 5'->3' nucleases, PIN and NYN domains []. | Short Name: | OST-HTH/LOTUS_dom |
