A Study On Cell Adhesion Molecules

3168 WordsNov 16, 201413 Pages
Name: Instructor’s Name: Course: Date: Cell Adhesion Molecules Introduction Cells are independent units of life. However, when a cell becomes part of an organism, it becomes part of a tissue and organ system. Cells in a tissue are joined to each other and to the extracellular matrix (ECM) by cell junctions. There are three kinds of cell junctions: Occluding junctions, anchoring junctions and communication junctions. Occluding junctions occur in the epithelium where the adjacent cells are so tightly sealed together that even small molecules cannot pass. Communicating junctions allow the exchange of chemical and electrical signals between cells. Anchoring junctions are the ones which attach a cell either to its neighbor or to the extracellular matrix. Formation of an anchoring junction requires the cells to stick to each other. Various molecules mediate adhesion between cells following which the cytoskeleton forms a structure around them. The anchoring junctions thus formed can be of four types- desmosomes, hemidesmosomes, focal adhesions and adherens junctions. In order for a proper tissue to form, it is important for the cells of the tissue to bind together. It is equally important to prevent the invasion and binding of other cells. Thus, cell adhesion has to be specific. This is where the cell adhesion molecules come into play (Alberts et al. 2002). Cell Adhesion Molecules (CAMs) Adhesion of cells to other cells and to the ECM is mediated by certain proteins on the
Open Document