Referenced in: none

Automatically associated channels: ClIC4 , Slo1

Title: Spontaneous skin erosions and reduced skin and corneal wound healing characterize CLIC4(NULL) mice.

Authors: V C Padmakumar, Kelsey Speer, Sonali Pal-Ghosh, Katelyn E Masiuk, Andrew Ryscavage, Samuel L Dengler, Shelly Hwang, John C Edwards, Vincenzo Coppola, Lino Tessarollo, Mary Ann Stepp, Stuart H Yuspa

Journal, date & volume: Am. J. Pathol., 2012 Jul , 181, 74-84

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/22613027

Abstract
Cutaneous wound healing is a complex process involving blood clotting, inflammation, migration of keratinocytes, angiogenesis, and, ultimately, tissue remodeling and wound closure. Many of these processes involve transforming growth factor-β (TGF-β) signaling, and mice lacking components of the TGF-β signaling pathway are defective in wound healing. We show herein that CLIC4, an integral component of the TGF-β pathway, is highly up-regulated in skin wounds. We genetically deleted murine CLIC4 and generated a colony on a C57Bl/6 background. CLIC4(NULL) mice were viable and fertile but had smaller litters than did wild-type mice. After 6 months of age, up to 40% of null mice developed spontaneous skin erosions. Reepithelialization of induced full-thickness skin wounds and superficial corneal wounds was delayed in CLIC4(NULL) mice, resolution of inflammation was delayed, and expression of β4 integrin and p21 was reduced in lysates of constitutive and wounded CLIC4(NULL) skin. The induced level of phosphorylated Smad2 in response to TGF-β was reduced in cultured CLIC4(NULL) keratinocytes relative to in wild-type cells, and CLIC4(NULL) keratinocytes migrated slower than did wild-type keratinocytes and did not increase migration in response to TGF-β. CLIC4(NULL) keratinocytes were also less adherent on plates coated with matrix secreted by wild-type keratinocytes. These results indicate that CLIC4 participates in skin healing and corneal wound reepithelialization through enhancement of epithelial migration by a mechanism that may involve a compromised TGF-β pathway.