FIGURE 3.

Teneurin domains downstream of the central scaffold region (A,B) The chicken Ten2 internal linker (A) as compared to the crystal structure of the cytotoxic C-terminal region of a Y. entomophaga C-protein (Busby et al., in preparation; PDB 6AQK) (B). Both are colored from N- to C-terminus according to the rainbow. (C) The chicken Ten2 internal linker domain is shown as ribbons inside a clipped surface representation of the Ten2 YD-shell (gray). The ABD and Tox-GHH are shown as red ribbons. (D) The Ten2 ABD and Tox-GHH domain are shown in surface representation and colored as in Figure 1A. The rest of the protein is shown as gray ribbons, oriented as in Figure 1A. (E) Structural alignment of the Ten2 Tox-GHH domain (red ribbon) and the nuclease domain of colicin E9 (white ribbon, PDB 1BXI). Side chains of the catalytically important residues and ions in colicin E9 are shown as sticks and spheres, respectively. The position of the predicted TCAP proteolysis site in Ten2 is indicated with a red arrowhead. (F) Structure-based sequence alignment of the Escherichia coli DNase colicins, all four human teneurin paralogs and chicken Ten2. Black arrowheads indicate the catalytically important residues of the colicins. Each red arrow corresponds to one β-strand.