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Updated: May 18, 2026
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Pharmacologic Induction of Epidermal Melanin and Protection Against Sunburn in a Humanized Mouse Model
Published on: September 7, 2013
Keratinocyte ATP binding cassette transporter expression is regulated by ultraviolet light
Lóránt Markó1, György Paragh, Péter Ugocsai
1Institute for Clinical Chemistry and Laboratory Medicine, University of Regensburg, Germany.
Journal of Photochemistry and Photobiology. B, Biology
|September 18, 2012
Summary
UVB light significantly alters the expression of ATP binding cassette (ABC) transporters in skin cells, impacting lipid transport and potentially causing epidermal barrier dysfunction.
Area of Science:
- Dermatology
- Molecular Biology
- Biochemistry
Background:
- ATP binding cassette (ABC) transporters regulate lipid homeostasis and are crucial for keratinocyte lipid transport.
- Ultraviolet (UV) light exposure induces epidermal stress, leading to lipid alterations and impaired lamellar body formation.
- Understanding UV-induced changes in ABC transporter expression is key to explaining skin barrier dysfunction.
Purpose of the Study:
- To investigate the impact of UVB irradiation on the expression of human ATP binding cassette (ABC) transporters in epidermal keratinocytes.
- To elucidate the molecular mechanisms underlying UVB-induced alterations in lipid transport proteins.
Main Methods:
- Analysis of mRNA levels for 47 human ABC transporters in UVB-treated keratinocytes.
- Confirmation of protein level changes for ABCA1 and ABCG1 using immunoblots.
- Luciferase reporter assays to assess the effect of UVB on ABCA1 and ABCG1 promoter activity.
Main Results:
- UVB markedly downregulated the mRNA levels of cholesterol transporters ABCA1 and ABCG1.
- UVB also downregulated ABCA12 and ABCC1, transporters involved in lipid and sphingolipid transport.
- The long splice variant of ABCF2 was rapidly upregulated post-UVB, while ABCA1 and ABCG1 protein levels and promoter activity were suppressed.
Conclusions:
- UVB irradiation significantly alters the expression and activity of key lipid transport proteins (ABC transporters) in keratinocytes.
- These UVB-induced changes in ABC transporters likely contribute to the observed epidermal barrier dysfunction after UV exposure.
- Findings provide insights into the molecular basis of skin barrier impairment following UV damage.
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