Roles of the functional domains and conserved residues of the severe fever with thrombocytopenia syndrome virus L protein provide insights into the viral RNA transcription/replication mechanism.

•All the domains of SFTSV-L protein were required for its function in viral RNA replication/transcription.•The influence of twelve conserved residues were evaluated, nine of which showed significance in the function of L protein.•Nine residues of SFTSV-L were strictly conserved among phleboviruses, suggesting its potency as a promising drug target.