Fig. 2

CHK interaction with the N protein occurs through the GAG-binding site of CHKs. A BLI sensorgrams of binding assays showing association and dissociation phases of the interaction between the N protein and CHKs, in the presence of GAG (left graphs). Prior to the association phase, CHKs were incubated with increasing concentrations of chondroitin sulfate (CS). The dotted line indicates the end of the association phase. The binding response of each CHK to N, in the absence of GAG (CS), was considered 100% of binding response (right graphs). Data represent the mean ± SEM of three independent experiments. The N protein does not bind CS [11]. B Proposed scenarios of CHK-N biomolecular interaction, where CHKs might bind to N through their receptor-binding site (scenario 1), or through their GAG-binding site (scenario 2). Prior incubation of CHKs with soluble GAGs blocks the GAG-binding site of CHKs, i.e., the CHK availability for interaction through its GAG-binding site