Role of E-Cadherin in Epithelial Architecture Maintenance

Abstract

Morphogenesis and architecture of a developing epithelium is controlled by both cell shape and contacts, mediated by spatially and temporally regulated cell adhesion molecules. The authors study if E-cadherin functions as a key factor of epithelial adhesion and epidermal architecture in vivo. They apply whole-mount digital deconvolution microscopy to evaluate three-dimensional (3D) E-cadherin expression during skin morphogenesis of Rhinella arenarum and in a cell adhesion alteration model. Results show morphogenetic changes in the 3D E-cadherin spatiotemporal expression pattern correlated with the increase of E-cadherin and in the number of cells with hexagonal geometry. Alterations in junction-protein phosphorylation showed drastic loss of E-cadherin and beta-catenin in cell-cell contacts and the increase of cytoplasm and nuclear beta-catenin in epidermis, suggesting the activation of the beta-catenin signal pathway. Surprisingly, no changes in cell shape and skin architecture were registered, suggesting that epidermal E-cadherin appears to be involved in signaling rather than cell contact maintenance in vivo.

A Quantitative Study of the Quality of Deconvolved Wide-field Microscopy Images as Function of Empirical Three-dimensional Point Spread Functions

“…However, there is evidence suggesting that high-quality deconvolution of images of thick objects can be achieved without introducing this complexity into the deconvolution algorithm [11,26]. In our lab, we have recently obtained similar images, using setups that are up to 25 μm below the cover slip [17]. These images have been very well deconvolved despite the considerable distance between the object and cover slip.…”

“…Particularly, E-cadherin is only present at the epidermis level; which is approximately 25 μm thick. After deconvolution, out-of-focus fluorescence reassignment unveiled a punctual pattern, where each bright dot represented cell-cell contacts that perform a ring of adherens junctions at cell boundaries (for details see [17]). Puncta are higher dots at two or three cell intersection than lateral contacts.…”

“…Stage-19 (Gosner, 1960 [16]) Rhinella arenarum embryos were treated to study the skin expression pattern of E-cadherin cell adhesion molecule, following Izaguirre's protocol [17]. They were fixed in Carnoy, washed in 1X PBS at room temperature (RT) and then treated with 0.1% Triton X-100 (SIGMA Chemical Company, St. Louis, USA) in PBS during 30 minutes at RT.…”

“…Finally, they were mounted in Vectashield mounting medium (Vector Laboratories, Vector Burlingame, CA) to prevent the fluorophores decay. According to skin thickness (≅ 25 μm) previously determined in morphological studies [17], 128 (32 μm) and 256 (38.4 μm) optic sections of 256 pixel x 256 pixel were collected with 40X and 100X, respectively.…”

Rubus idaeus L Inhibits Invasion Potential of Human A549 Lung Cancer Cells by Suppression Epithelial-to-Mesenchymal Transition and Akt Pathway In Vitro and Reduces Tumor Growth In Vivo

“…Epithelial cancer cells from in situ tumor or metastatic carcinoma lose contact with their neighbors because of the reduced expression of E-cadherin or α-catenin and the elevated expression of vimentin through the EMT program. 19 The epithelial molecule E-cadherin, which is known for regulating cell-to-cell contact, cell polarity, and cell shape, 20 connects adjacent cells through homophilic interactions and is linked to the cytoskeleton though the multi-catenin complex, including α-catenin and β-catenin, which are attached to their cytoplasmic tails. In this complex, β-catenin is directly associated with E-cadherin, whereas α-catenin is the link between β-catenin and the actin microfilament network of the cytoskeleton.…”