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07:29
Characterization of In Vitro Differentiation of Human Primary Keratinocytes by RNA-Seq Analysis
Published on: May 16, 2020
Plakoglobin deficiency protects keratinocytes from apoptosis
Rachel L Dusek1, Lisa M Godsel, Feng Chen
1Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611, USA.
The Journal of Investigative Dermatology
|November 18, 2006
Summary
Plakoglobin (Pg) deletion protects mouse keratinocytes from apoptosis by delaying cell death pathways and upregulating anti-apoptotic molecules. This suggests Pg may promote cell death, contrasting with beta-catenin
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- Plakoglobin (Pg) is crucial for cell-cell adhesion and epithelial integrity.
- The role of Pg in cell survival pathways is less understood compared to its homolog, beta-catenin.
Purpose of the Study:
- To investigate the function of plakoglobin (Pg) in regulating keratinocyte survival.
- To determine if Pg influences apoptosis in response to cellular stress.
Main Methods:
- Comparison of Pg-null and heterozygote mouse keratinocytes under apoptotic stimuli.
- Analysis of mitochondrial cytochrome c release and caspase-3 activation.
- Quantification of Bcl-X(L) mRNA and protein levels.
Main Results:
- Pg deletion significantly protected keratinocytes from apoptosis.
- Null cells showed delayed cytochrome c release and caspase-3 activation.
- Pg-null keratinocytes exhibited increased Bcl-X(L) expression.
- Reintroduction of Pg reversed the protective phenotype.
Conclusions:
- Plakoglobin (Pg) plays a pro-apoptotic role in keratinocytes, contrasting with beta-catenin's pro-survival function.
- Pg may limit the propagation of mutations by promoting the death of damaged cells.
- Pg's function extends beyond adhesion to actively regulate cell fate.
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