Molecular Basis For A Skin Fragility Syndrome

Keratins are proteins that form rod-like structures and assemble as a criss-crossed web within skin cells to give them structure and support from outside pressure. (Just imagine what’s happening to these cells when someone squeezes your arm or pinches your skin!) In EBS, mutations can occur in two of the many keratin genes present in skin cells. Coulombe and coworkers describe the mechanical properties of one of these defective keratin proteins. The mutation in keratin 14 changes a single amino acid, with dramatic effect. Whereas the normal protein makes filaments which then form bundles, like a sheaf of wheat, the mutated keratin protein cannot form the bundles, and consequently produces keratin networks that are more prone to breaking under stress. In addition, this mutant keratin makes filaments of greatly varying lengths, another factor expected to lower a cell’s resilience to external stress.

Whilst these results suggest how this particular mutation might contribute to the manifestation of EBS, further studies are required to determine how other keratin-based disorders, which do not affect filament structure so obviously, cause similar skin fragility diseases.

CONTACT:
Pierre Coulombe
tel +1 410 614 0510
e-mail pacoulom@welchlink.welch.jhu.edu

(C) Nature Cell Biology press release.

Message posted by: Trevor M. D'Souza