Transduction ligand binding specificity

Figure 8.1 Cytokine receptors usually display a unique cytokine ( ligand )-binding domain, but they share additional receptor components that are normally responsible for signal transduction. This explains the molecular basis of pleiotropy. IL-6, IL-11 and LIF receptors, for example, are all composed of a distinct ligand-specific binding domain and a separate subunit (gp 130). gp 130 is responsible for initiating signal transduction and is identical in all three receptors. This is depicted schematically above...

This increase is thought to be one of the early steps involved in so-called signal transduction and can result in the activation of enzyme systems responsible for subsequent metabolic or developmental changes. Lymphocytes show increases in intracellular calcium in response to many kinds of specific and nonspecific surface ligand binding, some of which lead to the cellular changes that we associate with an immune response. Many other classes of cells also show calcium changes in response to stimulation. 

---