Fig 2. Multiple sequence alignment of human β-tubulin isotypes.

The isotype βI shows variations of residues Val236-Ile, Cys239-Ser, Ala315-Cys, Val316-Ile and Thr351-Val, βIIa shows a change of Val316-Ile, βIII and βVI shows a change of Cys239-Ser, Ala315-Thr, and Thr351-Val at the indanocine binding pocket. Residue variations in the indanocine binding pocket are shown in red. Symbol ‘ * ‘ denotes positions of amino acid which have a single, fully conserved amino acid residue; the symbol ‘: ‘ denotes conservation between groups of strongly similar properties of amino acid; the symbol ‘.’ denotes the conservation between groups of weakly similar properties of amino acids, and the symbol ‘—‘ denotes gaps inserted to maximize sequence alignment [22].