Expression of a dominant-negative type II transforming growth factor β (TGF-β) receptor in the epidermis of transgenic mice blocks TGF-β-mediated growth inhibition

摘要

To determine whether a functional type II receptor of transforming growth factor β (TGF-β) is required to mediate the growth inhibitory effect of TGF-β on the skin in vivo, we have generated transgenic mice that overexpress a dominant negative-type II TGF-β receptor (△βRII) in the epidermis. The△βRII mice exhibited a thickened and wrin- kled skin, and histologically the epidermis was markedly hyperplastic and hyperkeratotic. In vivo labeling with BrdUrd showed a 2.5-fold increase in the labeling index over controls, with labeled nuclei occurring in both basal and suprabasal cells of transgenic epidermis.