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Metalloproteinase 9 is the outer executioner of desmoglein 3 in apoptotic keratinocytes

N Cirillo1, F Femiano, F Gombos

  • 1Regional Center on Craniofacial Malformations-MRI, Department of Odontostomatology, 1st School of Medicine and Surgery, II University of Naples, Naples, Italy. nicola.cirillo@unina2.it

Oral Diseases
|April 24, 2007
PubMed
Abstract

Insights

Matrix metalloproteinase-9 (MMP-9) specifically targets desmoglein 3 (Dsg3) on apoptotic keratinocytes. This MMP-9 activity impairs Dsg3, offering insights into related disease mechanisms.

Area of Science:

  • Cell biology
  • Biochemistry
  • Dermatology

Background:

  • Desmoglein 3 (Dsg3) is a key cadherin in desmosomes, crucial for keratinocyte adhesion.
  • Dysregulation of Dsg3 is implicated in blistering skin diseases.
  • Apoptosis in keratinocytes can lead to impaired cell adhesion.

Purpose of the Study:

  • To identify specific matrix metalloproteinases (MMPs) that target desmoglein 3 (Dsg3) during keratinocyte apoptosis.
  • To elucidate the role of MMPs in the cleavage of Dsg3 in apoptotic cells.

Main Methods:

  • Utilized inhibitor studies on cultured human keratinocytes undergoing apoptosis.
  • Employed Western blot analysis to detect Dsg3 cleavage and MMP activity.

Main Results:

  • Matrix metalloproteinase-9 (MMP-9) activity was found to be the primary cause of Dsg3 shedding from the cell surface in apoptotic keratinocytes.
  • Matrix metalloproteinase-2 (MMP-2) showed a minor role in Dsg3 cleavage.
  • MMPs including MMP-1, MMP-3, and MMP-8 were confirmed not to target Dsg3.

Conclusions:

  • Apoptotic keratinocytes utilize MMP-9 to cleave the extracellular domain of cell surface Dsg3.
  • This specific targeting of Dsg3 by MMP-9 provides a potential mechanism for understanding diseases associated with Dsg3 dysfunction.

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