p63 function: a hairy tale Available to Purchase

The transcription factor p63 is required for the development of the stratified skin epithelium and of hair follicles. But, although its role in early skin development is well understood, little is known about how p63 directs hair follicle morphogenesis. Now, Satrajit Sinha and co-workers report that ΔNp63α, the major p63 isoform expressed in skin, suppresses hair follicle differentiation in mice (see p. 1431). ΔNp63α, they report, is expressed in the developing hair placode but its expression is restricted to the outer root sheath (ORS), matrix cells and stem cells of the hair follicle bulge in mature hair. They show that targeted ΔNp63α overexpression in the ORS leads to dramatic defects in hair follicle development and hair cycling, and causes follicular keratinocytes to adopt an interfollicular cell fate. Global profiling and other experiments suggest that the loss of crucial signalling molecules, including Wnt/β-catenin, causes the hair follicle defects. Together, these...