General Signal Transduction

Signal transduction transmits and amplifies signals of stimuli from extracellular sources to the nucleus. Signaling molecules include various hormones, growth factors, metabolites, cytokines, chemokines, neurotransmitters, extracellular matrix components, receptors, protein kinases, protein phosphatases, and DNA-binding proteins. The purpose of signal transduction is to regulate the cellular response to the molecular stimuli via changes in gene and protein expression.