Signalingwegen

Signalingwege, or signaling pathways, are networks of molecular interactions that transmit information from outside the cell or from internal sensors to produce a coordinated response. They typically begin at a receptor or sensor, proceed through relay proteins and enzymes, and culminate in changes such as altered gene expression, metabolism, cell growth, differentiation, or programmed cell death. Signaling events involve amplification, modularity, and temporal dynamics, with signals integrated and modulated by cross-talk and feedback.

Key components include receptors (for example receptor tyrosine kinases and G protein–coupled receptors), intracellular transducers, kinases and phosphatases, second messengers (such as cAMP, Ca2+, and IP3), and transcription factors. Scaffold proteins organize signaling complexes and regulate specificity. Signals are terminated by phosphatases, phosphodiesterases, receptor desensitization, and degradation of messengers.

Well-characterized signaling pathways include MAPK/ERK, PI3K/AKT/mTOR, JAK/STAT, Wnt/β-catenin, TGF-β/SMAD, Notch, and NF-κB. These pathways control fundamental processes such as proliferation, survival, differentiation, immune responses, and metabolism. Dysregulation of signaling pathways can underlie diseases, including cancer, metabolic disorders, and developmental syndromes, and thus many therapies target signaling components, such as kinases, receptors, or adaptor proteins.

Research on Signalingwege integrates biochemistry, genetics, and systems biology to map interactions, quantify dynamics, and model network behavior. Understanding these pathways provides insight into cellular function and informs drug development and precision medicine.