Question

Differentiate between homotypic and heterotypic cell interaction

Answer 1

Answer:

Explanation:

Homotypic cell-cell interaction: Homologous cell interaction occurs at high cell density. It may involve gap junctional communication in which metabolites, second messengers such as cyclic AMP, diacylglycerol (DAG), Ca2+ , or electrical charge may be involved. This interaction harmonizes the expression of differentiation within a population of similar cells, rather than initiating its expression. Homotypic cell–cell adhesion molecules, (CAMs ) or cadherins, which are calcium-dependent, provide another mechanism by which contacting cells may interact. These adhesion molecules promote interaction primarily between like cells via identical, reciprocally acting, extracellular domains, and they appear to have signal transduction potential via phosphorylation of the intracellular domains.

Heterotypic cell-cell interaction : Heterologous cell interaction such as between mesodermally and endodermally or ectodermally derived cells is responsible for initiating and promoting differentiation. During and immediately after gastrulation in the embryo, and later during organogenesis, mutual interaction between cells originating in different germ layers promotes differentiation.