cellular adhesion

Cellular adhesion is a fundamental biological process that allows cells to recognize and bind to each other and to the extracellular matrix. This interaction is crucial for the development of single cells into multicellular organisms, enabling cells to specialize and integrate their functions within tissues.123

Proteins embedded in the cell membrane play a key role in this recognition and adhesion. These interactions are vital for forming distinct cell populations, organizing embryonic tissues, and maintaining the function of adult tissues. In some cases, like with slime mold amoebas, starvation can trigger cells to secrete compounds that cause them to stick together, forming aggregates.12

Cell adhesion also facilitates tissue and species recognition. For instance, dissociated sponge cells can reaggregate, but only with cells of the same species, a process mediated by specific proteoglycan molecules. In vertebrate animals, cell adhesion molecules (CAMs) on cell surfaces are responsible for distinguishing between different tissue types, leading to sorting and organization within developing embryos. Beyond recognition, specialized cell junctions, such as adhering junctions and tight junctions, provide mechanical stability and form seals between cells, particularly in epithelial tissues.21