Introduction to Signal Transduction

As commented before in the PRESENTATION, cells have developed mechanisms to be aware of extracellular alterations.

Cell Transduction Systems: Receptors and Second Messengers

Frequently in the cell membrane and sometimes in other locations, cells have receptors. Receptors are complex molecules that interact specifically with certain substances of the environment. After binding to these substances (e.g. hormones), receptors suffer an alteration of its tridimensional structure that results in changes in the concentration of certain molecules inside the cells, second messengers, that mediate the final response of the cells to the environmental modification previously detected by receptors. Sometimes, receptors themselves have the capacity of synthesize second messengers, but frequently other complex molecules that interact with receptors are needed for the production of those molecules.