Mechanism for coordinated RNA packaging and genome replication by rotavirus polymerase VP1.
Lu, X., McDonald, S.M., Tortorici, M.A., Tao, Y.J., Vasquez-Del Carpio, R., Nibert, M.L., Patton, J.T., Harrison, S.C.(2008) Structure 16: 1678-1688
- PubMed: 19000820 
- DOI: https://doi.org/10.1016/j.str.2008.09.006
- Primary Citation of Related Structures:  
2R7O, 2R7Q, 2R7R, 2R7S, 2R7T, 2R7U, 2R7V, 2R7W, 2R7X - PubMed Abstract: 
Rotavirus RNA-dependent RNA polymerase VP1 catalyzes RNA synthesis within a subviral particle. This activity depends on core shell protein VP2. A conserved sequence at the 3' end of plus-strand RNA templates is important for polymerase association and genome replication. We have determined the structure of VP1 at 2.9 A resolution, as apoenzyme and in complex with RNA. The cage-like enzyme is similar to reovirus lambda3, with four tunnels leading to or from a central, catalytic cavity. A distinguishing characteristic of VP1 is specific recognition, by conserved features of the template-entry channel, of four bases, UGUG, in the conserved 3' sequence. Well-defined interactions with these bases position the RNA so that its 3' end overshoots the initiating register, producing a stable but catalytically inactive complex. We propose that specific 3' end recognition selects rotavirus RNA for packaging and that VP2 activates the autoinhibited VP1/RNA complex to coordinate packaging and genome replication.
Organizational Affiliation: 
Laboratory of Molecular Medicine, Children's Hospital and Harvard Medical School, Boston, MA 02115, USA.