A Structure-Function Diversity Survey of the RNA-Dependent RNA Polymerases From the Positive-Strand RNA Viruses

Jia, Hengxia; Gong, Peng

In summary, we collected representative RdRPs encoded by positive-strand RNA viruses mainly at the level of virus family. By locating highly conserved residues within catalytic motifs within the RdRP ORF and by referencing structural and functional information of RdRPs in the literature, we tried to estimate the boundaries of the RdRP catalytic module in the full-length RdRP. Numerous regions beyond the RdRP catalytic module exist and many of them have either structure, or function, or both to be determined. Collectively, the global structure and regulatory functions related to regions beyond the catalytic module of the positive-strand RNA virus polymerases are quite diverse, and the current knowledge of these proteins is limited to only a few virus families. One purpose of our analyses is to provide a general guideline for researchers interested in these RdRP proteins and related viral systems to selectively or systematically investigate RdRPs with representative features. The global view of the positive-strand RNA virus RdRPs will continue to evolve with new virus species assigned, new structures determined, new functional regions identified, and new mechanisms dissected.