TABLE 1.

Binding of 3′ UTR or KL-3′ UTR RNA to NS5A(ΔAH) protein constructs of genotypes 1b and 2a as evaluated by filter binding assay^a

Genotype (clone) and binding partners	Kd, nM (mean ± SE)	Endpoint, % (mean ± SE)
1b (J4)
NS5A(ΔAH) + J4 3′ UTR	55 ± 1.0	85 ± 1.8
NS5A(ΔAH) + J4 KL-3′ UTR	59 ± 3.0	86 ± 2.7
NS5A(ΔAH) + control RNA	NDb	1.8 ± 0.63
NS5A(ΔAH) + JFH-1 3′ UTR	85 ± 3.1	73 ± 3.1
2a (JFH-1)
NS5A(ΔAH) + JFH-1 3′ UTR	57 ± 0.7	37 ± 6.2
NS5A(ΔAH) + JFH-1 KL-3′ UTR	54 ± 6.0	35 ± 7.3
NS5A(ΔAH) + control RNA	ND	1.6 ± 0.76
NS5A(ΔAH) + J4 3′ UTR	37 ± 6.7	46 ± 3.9

^aThe binding affinity and percentage of the total RNA bound to the NS5A proteins for interactions between 3′ UTR RNA and control FMDV 3C aptamer RNA are detailed. Results from comparative experiments to measure the genotype specificity of the NS5A(ΔAH)-3′ UTR interaction are also shown.

^bND, not determinable. The low affinity of NS5A(ΔAH) for the control aptamer RNA meant that it was not possible to calculate the K_d from the binding curve.