| First Author | Elkayam E | Year | 2017 |
| Journal | Nucleic Acids Res | Volume | 45 |
| Issue | 6 | Pages | 3528-3536 |
| PubMed ID | 27903888 | Mgi Jnum | J:250250 |
| Mgi Id | MGI:5923085 | Doi | 10.1093/nar/gkw1171 |
| Citation | Elkayam E, et al. (2017) siRNA carrying an (E)-vinylphosphonate moiety at the 5 end of the guide strand augments gene silencing by enhanced binding to human Argonaute-2. Nucleic Acids Res 45(6):3528-3536 |
| abstractText | Efficient gene silencing by RNA interference (RNAi) in vivo requires the recognition and binding of the 5- phosphate of the guide strand of an siRNA by the Argonaute protein. However, for exogenous siRNAs it is limited by the rapid removal of the 5- phosphate of the guide strand by metabolic enzymes. Here, we have determined the crystal structure of human Argonaute-2 in complex with the metabolically stable 5-(E)-vinylphosphonate (5-E-VP) guide RNA at 2.5-A resolution. The structure demonstrates how the 5 binding site in the Mid domain of human Argonaute-2 is able to adjust the key residues in the 5-nucleotide binding pocket to compensate for the change introduced by the modified nucleotide. This observation also explains improved binding affinity of the 5-E-VP -modified siRNA to human Argonaute-2 in-vitro, as well as the enhanced silencing in the context of the trivalent N-acetylgalactosamine (GalNAc)-conjugated siRNA in mice relative to the un-modified siRNA. |
