Conditional knockout of N-WASP in mouse fibroblast caused keratinocyte hyper proliferation and enhanced wound closure

Sci Rep. 2016 Dec 2:6:38109. doi: 10.1038/srep38109.

Abstract

Neural-Wiskott Aldrich Syndrome Protein (N-WASP) is expressed ubiquitously, regulates actin polymerization and is essential during mouse development. We have previously shown that N-WASP is critical for cell-ECM adhesion in fibroblasts. To characterize the role of N-WASP in fibroblast for skin development, we generated a conditional knockout mouse model in which fibroblast N-WASP was ablated using the Cre recombinase driven by Fibroblast Specific Protein promoter (Fsp-Cre). N-WASPFKO (N-WASPfl/fl; Fsp-cre) were born following Mendelian genetics, survived without any visible abnormalities for more than 1 year and were sexually reproductive, suggesting that expression of N-WASP in fibroblast is not critical for survival under laboratory conditions. Histological sections of N-WASPFKO mice skin (13 weeks old) showed thicker epidermis with higher percentage of cells staining for proliferation marker (PCNA), suggesting that N-WASP deficient fibroblasts promote keratinocyte proliferation. N-WASPFKO mice skin had elevated collagen content, elevated expression of FGF7 (keratinocyte growth factor) and TGFβ signaling proteins. Wound healing was faster in N-WASPFKO mice compared to control mice and N-WASP deficient fibroblasts were found to have enhanced collagen gel contraction properties. These results suggest that N-WASP deficiency in fibroblasts improves wound healing by growth factor-mediated enhancement of keratinocyte proliferation and increased wound contraction in mice.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Proliferation / genetics
  • Cell Proliferation / physiology
  • Collagen / metabolism
  • Epidermal Cells
  • Epidermis / metabolism
  • Fibroblast Growth Factor 7 / metabolism
  • Fibroblasts / cytology*
  • Fibroblasts / metabolism*
  • Keratinocytes / cytology*
  • Keratinocytes / metabolism*
  • Male
  • Mice
  • Mice, Knockout
  • Signal Transduction
  • Transforming Growth Factor beta / metabolism
  • Wiskott-Aldrich Syndrome Protein, Neuronal / deficiency*
  • Wiskott-Aldrich Syndrome Protein, Neuronal / genetics
  • Wound Healing / genetics
  • Wound Healing / physiology

Substances

  • Fgf7 protein, mouse
  • Transforming Growth Factor beta
  • Wasl protein, mouse
  • Wiskott-Aldrich Syndrome Protein, Neuronal
  • Fibroblast Growth Factor 7
  • Collagen