1Diapositiva 12

Notes

[Diapositiva 1] Signaling Complexes and Scaffold/Adaptor Proteins [Diapositiva 2] Signaling Proteins Do not exist as individual, soluble, randomly diffusing components floating around in the cytoplasm Would rarely have the 5 or more components come together for signal transduction Regulation would be very difficult (Good, MC. et al. 2011. Science . 332:680) [Diapositiva 3] Instead: Organized into localized transduction units Specifically tailored to respond to a particular signal Co-localized Lipid rafts Compartmentalized into organelles Scaffold-Mediated Complex (Good, MC. et al. 2011. Science . 332:680) [Diapositiva 4] Signal transduction units or Signaling Complexes Organize components so that signals flow: Transmembrane receptors Protein kinases Phosphatases Other components and substrates Must compartmentalize these units To spatially segregate broad specificity kinases and phosphatases Prevents non-specific phosphorylation of other proteins Allow interaction between multiple signaling pathways [Diapositiva 5] Receptor Tyrosine Kinases Phosphorylations create binding sites for: SH2 domains PTB domains Present on signaling proteins Multi-docking Protein [Diapositiv...