In the amyloid core of fibrils derived from PSP patients, the FoldB conformation of PAM4 forms a partial heterotypic steric zipper interface of exceptional stability with PHF6 that staples one side of the elongated fibril core, whereas the other side is stabilised through interdigitation of the PHF6*, 326GNIHHK331 and 337VEVKSE342 amyloid motifs, respectively (Fig. 6g). This evidence concerns the gene PHF6 and supranuclear palsy, progressive, 1.