Pannexin1 (Panx1), a channel-forming glycoprotein is expressed in neonatal but not aged mouse skin. Histological staining of Panx1 knockout (KO) mouse skin revealed a reduction in epidermal and dermal thickness but an increase in hypodermal adipose tissue. Following dorsal skin punch biopsies, mutant mice exhibited a significant delay in wound healing. Scratch wound and proliferation assays revealed that cultured keratinocytes from KO mice were more migratory while dermal fibroblasts were more proliferative than controls. Additionally, collagen gels populated with fibroblasts from KO mice exhibited significantly reduced contraction, comparable to WT fibroblasts treated with the Panx1 blocker, probenecid. KO fibroblasts did not increase α-smooth muscle actin expression in response to TGF-β, as is the case for differentiating WT myofibroblasts during wound contraction. We conclude that Panx1 controls cellular properties of keratinocytes and dermal fibroblasts during early stages of skin development and modulates wound repair upon injury.Journal of Investigative Dermatology accepted article preview online, 12 February 2014; doi:10.1038/jid.2014.86.