The structure of human trichohyalin. Potential multiple roles as a functional EF-hand-like calcium-binding protein, a cornified cell envelope precursor, and an intermediate filament-associated (cross-linking) protein.

摘要: Trichohyalin is an intermediate filament-associated protein that associates in regular arrays with keratin filaments (KIF) of the inner root sheath cells hair follicle and granular layer epidermis a known substrate transglutaminases. We have determined full-length sequence human trichohyalin by use RNA-mediated anchored polymerase chain reaction methods from genomic clone analyzed its potential secondary structure. show here may at least three important functions these cells. The 248 kDa unusual it contains one highest contents charged residues any protein. Of several defined domains, domains 2-4, 6, 8 are almost entirely alpha-helical, configured as series peptide repeats varying regularity, thought to form single-stranded alpha-helical rod stabilized ionic interactions between successive turns alpha-helix. Domain 6 most bind KIF directly interactions. Domains 5 7 less well organized introduce folds molecule. Thus, predicted be elongated flexible 215 nm long function KIF-associated cross-linking loose networks. In addition, similar to, but times longer than, involucrin, cell envelope constituent, so together, involucrin serve scaffold proteins organization or even anchor network. Finally, possesses pair functional calcium-binding EF-hand type amino terminus involved calcium-dependent postsynthetic processing during terminal differentiation.