| ID | Fold | PDBID | PDB annotation | Length | RFam ID |
| 4U50_7 | 27 | 4U50 | 5S ribosomal RNA | 121 | RF00001 |
| 4U50_8 | 544 | 4U50 | 5.8S ribosomal RNA | 158 | RF00002 |
| 4U51_2 | 56 | 4U51 | 18S ribosomal RNA | 1800 | RF01960 |
| 4U51_1 | 53 | 4U51 | 25S ribosomal RNA | 3396 | RF02543 |
| 4U51_3 | 27 | 4U51 | 5S ribosomal RNA | 121 | RF00001 |
| 4U51_4 | 544 | 4U51 | 5.8S ribosomal RNA | 158 | RF00002 |
| 4U51_6 | 56 | 4U51 | 18S ribosomal RNA | 1800 | RF01960 |
| 4U51_5 | 53 | 4U51 | 25S ribosomal RNA | 3396 | RF02543 |
| 4U51_7 | 27 | 4U51 | 5S ribosomal RNA | 121 | RF00001 |
| 4U51_8 | 544 | 4U51 | 5.8S ribosomal RNA | 158 | RF00002 |
| 4U52_2 | 56 | 4U52 | 18S ribosomal RNA | 1800 | RF01960 |
| 4U52_1 | 53 | 4U52 | 25S ribosomal RNA | 3396 | RF02543 |
| 4U52_3 | 27 | 4U52 | 5S ribosomal RNA | 121 | RF00001 |
| 4U52_4 | 544 | 4U52 | 5.8S ribosomal RNA | 158 | RF00002 |
| 4U52_6 | 56 | 4U52 | 18S ribosomal RNA | 1800 | RF01960 |
| 4U52_5 | 53 | 4U52 | 25S ribosomal RNA | 3396 | RF02543 |
| 4U52_7 | 27 | 4U52 | 5S ribosomal RNA | 121 | RF00001 |
| 4U52_8 | 544 | 4U52 | 5.8S ribosomal RNA | 158 | RF00002 |
| 4U53_2 | 56 | 4U53 | 18S ribosomal RNA | 1800 | RF01960 |
| 4U53_1 | 53 | 4U53 | 25S ribosomal RNA | 3396 | RF02543 |
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