| First Author | Jung S | Year | 2020 |
| Journal | Nucleic Acids Res | Volume | 48 |
| Issue | 18 | Pages | 10397-10412 |
| PubMed ID | 32946572 | Mgi Jnum | J:296463 |
| Mgi Id | MGI:6467728 | Doi | 10.1093/nar/gkaa739 |
| Citation | Jung S, et al. (2020) A ribosomal RNA fragment with 2',3'-cyclic phosphate and GTP-binding activity acts as RIG-I ligand. Nucleic Acids Res 48(18):10397-10412 |
| abstractText | The RNA helicase RIG-I plays a key role in sensing pathogen-derived RNA. Double-stranded RNA structures bearing 5'-tri- or diphosphates are commonly referred to as activating RIG-I ligands. However, endogenous RNA fragments generated during viral infection via RNase L also activate RIG-I. Of note, RNase-digested RNA fragments bear a 5'-hydroxyl group and a 2',3'-cyclic phosphate. How endogenous RNA fragments activate RIG-I despite the lack of 5'-phosphorylation has not been elucidated. Here we describe an endogenous RIG-I ligand (eRL) that is derived from the internal transcribed spacer 2 region (ITS2) of the 45S ribosomal RNA after partial RNase A digestion in vitro, RNase A protein transfection or RNase L activation. The immunostimulatory property of the eRL is dependent on 2',3'-cyclic phosphate and its sequence is characterized by a G-quadruplex containing sequence motif mediating guanosine-5'-triphosphate (GTP) binding. In summary, RNase generated self-RNA fragments with 2',3'-cyclic phosphate function as nucleotide-5'-triphosphate binding aptamers activating RIG-I. |
