målmolekylet

målmolekylet, or target molecule, is a biomolecule that a drug or other agent interacts with to produce a biological effect. In pharmacology and biochemistry, the term designates the molecule whose function is modulated by binding of a ligand, inhibitor, activator, or modulator. Target molecules include proteins such as receptors (for example G protein-coupled receptors and receptor tyrosine kinases), enzymes (like cyclooxygenases, kinases), transporters and ion channels, as well as nucleic acids or protein-protein interaction surfaces. The choice of målmolekylet determines the mechanism of action, such as competitive inhibition, allosteric modulation, or activation, and influences selectivity and pharmacodynamics.

Target identification and validation are key steps in drug discovery. Target identification aims to link a disease phenotype to a molecule that, when modulated, yields a therapeutic effect. Validation demonstrates that engagement with the target produces the intended outcome in cellular and animal models, and that altering the target has a measurable therapeutic benefit with manageable safety. Techniques used include genetic approaches (RNA interference, CRISPR), proteomics and chemoproteomics, affinity-based pull-downs, and phenotypic screening followed by target deconvolution.

In research and clinical contexts, målmolekyler guide screening, lead optimization, and biomarker selection. Knowledge about expression patterns, tissue distribution, and potential off-target interactions informs risk assessment and the likelihood of efficacy. The concept is central across drug discovery, pharmacology, and precision medicine.