Beta-catenin activity in the dermal papilla of the hair follicle regulates pigment-type switching.

ABSTRACT: The switch between black and yellow pigment is mediated by the interaction between Melanocortin receptor 1 (Mc1r) and its antagonist Agouti, but the genetic and developmental mechanisms that modify this interaction to obtain different coat color in distinct environments are poorly understood. Here, the role of Wnt/?-catenin signaling in the regulation of pigment-type switching was studied. Loss and gain of function of ?-catenin in the dermal papilla (DP) of the hair follicle results in yellow and black animals, respectively. ?-Catenin activity in the DP suppresses Agouti expression and activates Corin, a negative regulator of Agouti activity. In addition, ?-catenin activity in the DP regulates melanocyte activity by a mechanism that is independent of both Agouti and Corin. The coordinate and inverse regulation of Agouti and Corin renders pelage pigmentation sensitive to changes in ?-catenin activity in the DP that do not alter pelage structure. As a result, the signals that specify two biologically distinct quantitative traits are partially uncoupled despite their common regulation by the ?-catenin pathway in the same cells.

SUBMITTER: Enshell-Seijffers D 

PROVIDER: S-EPMC3003114 | biostudies-literature | 2010 Dec

REPOSITORIES: biostudies-literature