Biological targeting

While some biological targets such as DNA are not protein in nature, most receptors are. It is useful to consider the properties of receptor proteins to provide a context for the interaction of small molecule drugs with them. An important property of receptors is that they have a 3D structure. Proteins usually are comprised of one or... 

A major approach to discovery is the target-based approach, whereby a single biological target is... 

Biological targets may consist of single-entity proteins, complexes of receptors (dimers), or receptors plus accessory proteins. Mixtures of gene products can produce unique phenotypic biological targets. 

As well as complex biological targets, complex chemical targets (drugs with multiple activity, prodrugs) can be used to produce therapeutically useful phenotypic responses. 

Alkylating agent, a reactive chemical that forms a covalent bond with chemical moieties on the biological target (usually a protein). For instance, p-haloalkylamines generate an aziridinium ion in aqueous base that inserts into -SH, -CHOH, or other chemical structures in peptides. Once inserted, the effects of the alkylating agent are irreversible. 

Downregnlation, the reduction in the number of biological targets (e.g., cell surface receptors, enzymes) usually... 

Genetic polymorphism, due to two or more alleles in a gene leading to more than one phenotype with respect to biological target reactivity to drugs. 

Genotype, the pattern of genes inherited by an individual. The makeup of a biological target due to coding of the gene for that target. 

Ligand binding, a biochemical technique that measures the physical association of a ligand with a biological target (usually a protein) see Chapter 4.2. 

Polymorphisms, in pharmacology, these are associated with genetic polymorphisms of biological targets (see Genetic polymorphisms). 

Tang Herbal, 147 Target-based drug discovery biological targets, 180-184 chemical end point in, 180 chemical tools, 178-179 definition of, 5 description of, 175-177 linear approach, 176 orphan receptors, 180 preclinical process in, 176-177 random variation in gene expression, 178... 

Inhibitors of the Angiopoietin/Tie-2 and Ephrin/Eph systems are in preclinical development which parallels the biological target validation of these molecules. As vascular assembly, maturation, and homeostasis regulating molecules, therapeutic interference with these molecular systems may hold promise for a number of vascular indications. 

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