FIGURE 5.

TCRV NP resembles LASV NP in the tertiary structure, exoribonuclease activity, and IFN suppressive function. A, schematic diagram of TCRV NP-C structure, with the five catalytic residues shown in a stick model. B, superimposition of LASV and TCRV NP-C structures, shown in yellow and green, respectively. The residue numbers are based on LAVS nucleoprotein. The Arg-393, Tyr-429, and Lys-488 in LASV NP are replaced by Pro-390, His-426, and Ser-485 in TCRV NP, respectively. C, TCRV NP has similar 3′-5′ exoribonuclease activity with dsRNA substrate preference as LASV NP. A representative gel of at least three independent experiments was shown for each protein. D, TCRV and LASV NPs can equally suppress Sendai virus-induced IFN production in the LUC-based promoter assay. The results shown are the average of three independent experiments with error bars showing S.D. Statistical analyses were conducted using the Student's t test. ***, p < 0.001.