C_D_box_snoRNA_gene U3_snoRNA_gene sequence SO:0002378 evan A gene that codes for U3_snoRNA. U3 snoRNA is a member of the box C/D class of small nucleolar RNAs. The U3 snoRNA secondary structure is characterised by a small 5' domain (with boxes A and A'), and a larger 3' domain (with boxes B, C, C', and D), the two domains being linked by a single-stranded hinge. Boxes B and C form the B/C motif, which appears to be exclusive to U3 snoRNAs, and boxes C' and D form the C'/D motif. The latter is functionally similar to the C/D motifs found in other snoRNAs. The 5' domain and the hinge region act as a pre-rRNA-binding domain. The 3' domain has conserved protein-binding sites. Both the box B/C and box C'/D motifs are sufficient for nuclear retention of U3 snoRNA. The box C'/D motif is also necessary for nucleolar localization, stability and hypermethylation of U3 snoRNA. Both box B/C and C'/D motifs are involved in specific protein interactions and are necessary for the rRNA processing functions of U3 snoRNA. small nucleolar RNA U3 gene, snoRNA U3 gene, U3 small nucleolar RNA gene, U3 snoRNA gene 2021-11-19T05:50:57Z Added at the request of Steven Marygold. See GitHub Issue #519 (https://github.com/The-Sequence-Ontology/SO-Ontologies/issues/519).