Receptor Tyrosine Kinases Mediated Cell Signalling Pathways

A small number of signalling pathways, including receptor tyrosine kinases (RTKs) and G protein-coupled receptors (GPCRs), are activated by plasma membrane in order for cells to respond external cues. In addition transmitting, these pathways also process, encode, integrate both internal signals. recent years, it has become clear that different spatio-temporal activation profiles the same set proteins lead gene-expression patterns various physiological responses. These findings suggest precise temporal control relative spatial distribution signal transducers necessary important cellular decisions such as cytoskeletal reorganisation, cell-cycle checkpoints, cell death (apoptosis). Due their crucial function embryogenesis, survival, motility, proliferation, differentiation, glucose metabolism, apoptosis, RTK-mediated have drawn a lot attention from scientists. significant serious human diseases, diabetes, cancer, chronic inflammatory syndromes, developmental defects, caused RTK dysfunction. RTKs undergo allosteric transitions (the insulin receptor, instance) or dimerization response stimulation, which activates intrinsic tyrosine-kinase activity. Numerous cytoplasmic receive biochemical subsequent phosphorylation numerous residues on causes them move surface. Through intricate circuits protein-protein interactions covalent modification cascades, resulting reactions take place. The earlier theories discrete linear connected extracellular signals expression particular genes, been replaced an emerging picture interconnected networks, raising concerns about specificity signal-response events. actuality, all share common protein complement mediates transduction downstream RTKs. nuclear transcription factors is induced kinase phosphatase mitogen-activated (MAPK) GPCRs There no single gene determines any given pathway. Instead, dynamics components specificity. classic example distinctive biological EGF nerve growth factor stimulation PC12 lines (NGF). Cell proliferation temporarily EGF, whereas differentiation triggered sustained MAPK NGF. However, there many variables affect how cascades behave. Depending heavily subcellular localization recruitment scaffold proteins, can produce oscillations, abrupt switches, bistable dynamics.