Dochow et al_JBC_revised

Background: RNA-dependent RNA-polymerases of nonsegmented negative-strand RNA viruses (Mononegavirales) harbor multiple catalytic activities. Results: Domain screening and transcomplementation of paramyxovirus polymerase fragments with dimerization tags identifies independent folding-competent domains. Conclusion: Paramyxovirus polymerases harbor at least two independent domains that lack highaffinity interfaces but require molecular compatibility for bioactivity. Significance: First demonstration of Mononegavirales polymerase transcomplementation sets the stage for structural analyses of folding domains.