Related Experiment Video
Updated: May 13, 2026

Functional Assessment of Intestinal Tight Junction Barrier and Ion Permeability in Native Tissue by Ussing Chamber Technique
Published on: May 26, 2021
Tight junction dysfunction in the stratum granulosum leads to aberrant stratum corneum barrier function in
Tomoko Sugawara1, Noriko Iwamoto, Masaya Akashi
1Division of Cell Biology, Department of Physiology and Cell Biology, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan.
Background:
Tight junctions (TJs) contribute to the epithelial barrier function by preventing leakage of solutes through the intercellular space. In the skin, TJs occur in the stratum granulosum (SG), where claudin-1 and claudin-4 are expressed as adhesion molecules of TJs. Claudin-1-deficient (Cldn1(-/-)) mice die within one day of birth accompanied by excessive transepidermal water loss, indicating a critical role of TJs in the epidermal barrier function. However, it has been debated whether the impaired TJ function in the SG also affects the stratum corneum (SC) barrier function or whether it results in skin barrier defects despite a normal SC barrier.
Objective:
To clarify whether the impaired TJ function affects the SC barrier function in Cldn1(-/-) mice.
Methods:
The morphology, barrier function and biochemical characteristic of the SC were compared between Cldn1(-/-) and Cldn1(+/+) mice.
Results:
Scanning electron microscopy demonstrated abnormally wrinkled and rough corneocytes in Cldn1(-/-) mice. Notably, the X-gal tracer easily permeated into the Cldn1(-/-) SC, and water evaporation through isolated Cldn1(-/-) SC sheets was significantly higher than that through Cldn1(+/+) SC sheets. Furthermore, the ceramide composition of the SC lipids and filaggrin processing were altered in Cldn1(-/-) mice.
Conclusion:
Cldn1(-/-) mice exhibited the abnormal SC formation and SC barrier defects. These findings demonstrate for the first time that TJs in the SG play crucial roles in the complete SC formation and SC barrier function.
Related Concept Videos
Tight Junctions
Desmosomes
Cells of the Epidermis
The cells in all these layers except the stratum basale are called keratinocytes, a type of cell that manufactures and stores the protein keratin. The keratinocytes in the stratum corneum are dead and regularly slough away, being replaced by cells from...
Notch Signaling Pathway
The Notch gene came into the limelight in 1914 after the discovery that its mutation in Drosophila melanogaster leads to a serrated (or "notched") wing margin phenotype. It was not until 1985...
Role Of Notch Signalling In Intestinal Stem Cell Renewal
Direct cell-to-cell contact is needed for the activation of Notch signaling. The signal is initiated when a notch ligand binds to a receptor on an adjacent cell, also...
Cytoskeletal Linker Proteins - Plakins

