Question

Contrast properties of an epithelial tissue with those of a mesenchymal tissue. How are cadherins related to the transition of epithelium to mesenchyme; How is this transition regulated or triggered?

Answer 1

Epithelial & mesenchymal cell are two different types of cell which show transition between those two cell type during the process of embryonic development. Epithelial cell came from epithelial tissue whereas mesenchymal cell came from connective tissue. The biggest difference between the epithelial cell and the mesenchymal cell is that epithelial cell are present to line organs, vessels, and cavities which provide protection to them wherever the mesenchymal cell are differentiated into different type of tissue like smooth muscle or vascular endothelium or rconnective tissue or supporting tissues or blood cell

Definition
Epithelial Cells: They are the cells those which are arranged in layers of single or many, forming a lining on the surface of the body.

Mesenchymal Cells: They are the stellate cells or fusiform of the cell which are mostly located in between endoderm & ectoderm in a young embryo.

Origins
Epithelial Cells: They are derivatives of endoderm, ectoderm and mesoderm.

Mesenchymal Cells:They are derivative of mesoderm. Few of mesenchymal cells which are developed in surface ectoderm or neural crest.

Transition
Epithelial Cells:They are capable of transition to mesenchymal cells during EMT.

Mesenchymal Cells: They are thecells which are capable of transition to epithelial cells during MET.

Levels of Differentiation
Epithelial Cells:They are specialized cells.

Mesenchymal Cells: They are unspecialized cells.

The transition from epithelial to mesenchymal is the process through which epithelial cell loses their polarity of cell and adhesion between cell-cell and gain migratory as well as invasive property which becomes mesenchymal cells; those cells are multipotent stromal cells which can be differentiated into a different variety of types of cell. EMT are very essential for most of the process during developement including the mesoderm formation as well as neural tube. EMT also has been seen to occur during healing of a wound, during fibrosis of in organ as well as during the process of initiation in metastasis during progression of cancer.Epithelial and mesenchymal cells havr different phenotype and function ae well, even though they both share inherent plasticity.Epithelial cell have E-cadherin in high levels, whereas mesenchymal cells have N-cadherin, vimentin and fibronectin. So, EMT entails profound phenotypic and morphological change in the cell.