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In Vivo Biosensor Tracks Non-apoptotic Caspase Activity in Drosophila
Published on: November 27, 2016
Epidermal differentiation does not involve the pro-apoptotic executioner caspases, but is associated with caspase-14
S Lippens1, M Kockx, M Knaapen
1Molecular Signaling and Cell Death Unit, Department of Molecular Biology, Flanders Interuniversity Institute for Biotechnology and Ghent University, K.L. Ledeganckstraat 35, B-9000 Ghent, Belgium.
Cell Death and Differentiation
|February 15, 2001
Summary
Caspase-14 is crucial for normal skin cornification, as it is synthesized by differentiating keratinocytes. Executioner caspases are not involved in this programmed cell death process.
Area of Science:
- Dermatology
- Cell Biology
- Biochemistry
Background:
- The epidermis, a stratified squamous epithelium, involves keratinocyte terminal differentiation and programmed cell death.
- The role of caspases, a family of proteases, in epidermal differentiation is not fully understood.
Purpose of the Study:
- To investigate the role of caspase-14 in keratinocyte terminal differentiation and programmed cell death.
- To determine if executioner caspases (caspase-3, -6, -7) are involved in epidermal differentiation.
Main Methods:
- Studied caspase-14 synthesis and processing in differentiating keratinocytes.
- Examined caspase activation in response to death-inducing stimuli.
- Compared caspase-14 expression in normal skin, oral epithelium, and psoriatic lesions.
Main Results:
- Caspase-14 synthesis is restricted to differentiating keratinocytes and its processing correlates with terminal epidermal differentiation.
- Pro-apoptotic executioner caspases (-3, -6, -7) are not activated during epidermal differentiation.
- Caspase-14 does not mediate apoptosis in differentiated keratinocytes, unlike caspase-3. Non-cornifying oral epithelium and psoriatic lesions show low caspase-14 levels.
Conclusions:
- Caspase-14 plays a significant role in the keratinocyte terminal differentiation program, leading to normal skin cornification.
- Executioner caspases are not implicated in the process of epidermal differentiation and cornification.
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