Video - Cell signaling pathways

Cell signaling pathways are how cells communicate with each other to carry out their functions. There are many different types of cell signaling pathways, but they all share some common features. Signals are classified into three main groups based on the distance they travel. These include autocrine signals, which target the same cell as the origin; paracrine signals which target nearby cells; and endocrine signals which target distant cells. Cell signaling pathways rely on proteins called receptors located on the cells' surface. We have three major transmembrane receptor classes: G protein-coupled receptors, enzyme-coupled receptors, and ion channel receptors. When a molecule that is part of a cell signal binds to a receptor, it triggers a series of reactions inside the cell that ultimately lead to the desired outcome.