Cellular signaling pathway

A cellular signaling pathway refers broadly to the series of molecular events by which cells sense external cues and translate them into functional responses. This process typically involves extracellular signals (ligands), cell surface or intracellular receptors that detect those signals, secondary messengers that amplify them inside the cell, and downstream effectors that execute changes such as altered gene expression or metabolic activity. There are multiple types—including autocrine, paracrine, endocrine—and they regulate virtually all aspects of cell biology from proliferation to apoptosis. The term does not refer to a single molecule but rather encompasses entire networks involving numerous proteins like G protein-coupled receptors, tyrosine kinases, ion channels, second messengers like cAMP/Ca²⁺/IP₃/DAG, transcription factors, etc.

Other names

Cell signaling pathwaySignal transduction pathwayIntracellular signaling cascadeCell communication pathway