Figure 6.

Sequence alignments of villin-type headpiece domains. (a) The sequence of human supervillin headpiece is aligned to that of human dematin headpiece and chicken villin headpiece. Both the numbering and position of the helices are referenced to the ensemble structure of supervillin (2K6M). Boxed letters indentify those residues believed to be involved in F-actin binding, bolded letters correspond to those residues that are positioned similarly to Lys38 (the positive patch) in villin headpiece. (b) ClustalW sequence alignment of supervillin headpiece domains from several species demonstrate 100% conservation of Leu38 (bolded, boxed). We have previously correlated the presence or absence of a positive patch with F-actin binding activity in a number of different villin-type headpiece domains.⁸,¹¹