Fig. 1.

Proposed role of CCN3 in melanocyte adhesion. a In resting skin, melanocytes are localized to the basement membrane via multiple adhesion mechanisms including integrin–laminin binding and/or DDR1-collagen IV binding. b Under conditions of stress such as ultra violet (UV) irradiation, integrin–laminin connections are disrupted. A potential mechanism by which melanocytes maintain adhesion to the basement membrane involves the production and release of IL-1ß by keratinocytes in resonse to stress. IL-1ß stimulates CCN3 production and secretion by melanocytes. CCN3 then acts in an autocrine manner, to enhance collagen receptor DDR1 expression in melanocytes, promoting adhesion to collagen IV in the basement membrane