Crystal structure of the tubulin tyrosine carboxypeptidase complex VASH1–SVBP

The cyclic enzymatic removal and ligation of the C-terminal tyrosine of α-tubulin generates heterogeneous microtubules and affects their functions. Here we describe the crystal and solution structure of the tubulin carboxypeptidase complex between vasohibin (VASH1) and small vasohibin-binding protein (SVBP), which folds in a long helix, which stabilizes the VASH1 catalytic domain. This structure, combined with molecular docking and mutagenesis experiments, reveals which residues are responsible for recognition and cleavage of the tubulin C-terminal tyrosine. Crystal structure of the tubulin carboxypeptidase complex between vasohibin and SVBP, combined with mutagenesis, reveals the residues responsible for substrate recognition and cleavage.