Atomic homology model of the extracellular domain of the Navβ1 subunit.

<p>(A) The functionally relevant residues identified are shown in magenta. Cysteine 43 was predicted to form a disulphide bond with cysteine 21 and arginine 89 may form a salt bridge with glutamate 87. The buried disulphide bridge between C40 and C121 is also shown. (B) The model of β1 (cyan) was superimposed over the template structure, myelin protein P0 (gray), and 3 Ig-like proteins including NTRK2_HUMAN, TRGC2_HUMAN, and a camelid VHH antibody (PDB codes: 1neu_A, 1wwb_X, 1hxm_B, 1kxq_H). Despite their divergent functions, the general topologies of the crystal structures were conserved. The conserved basic residues at the position equivalent to Arg89 are displayed as atom sticks (colour code: β1 model in cyan, 1wwb_X in marine blue, 1hxm_B in magenta, and 1kxq_H in yellow).