FIG. 3.

(A) SMN exons 2 and 6 independently mediate NS2 binding. GST-NS2 immobilized on a rabbit anti-mouse sensor chip using anti-NS2 antibody was pulsed with GST-SMN fusion proteins (full-length SMN [SMN-FL], SMN exons 1 to 4, 5 to 7, 1, 2, 3, 4, and 6) and His exons 6 to 7 alone. Values represent binding of SMN constructs above a background control as response units (RU) and the mean of three separate experiments. (B) A schematic representation of the SMN protein. Previously reported physical and functional domains, amino acid positions, exon borders, and the relative positions of the three missense mutations (∗) analyzed in Fig. 4 are indicated.