BIL 255 Lecture Notes - Lecture 19: Cell Signaling, Protein Kinase B, Rhabdomyosarcoma
Document Summary
Intracellular signaling cascades achieve astonishing speed, sensitivity and adaptability. Can detect light across six orders of magnitude. Within 2 seconds, our lights can adapt to the brightness of the sun which is mediated by this cell. Sensitivity, speed, and feedback that leads to attenuation of the response of the cells and allows the ability to see across so many orders of magnitude. Receptor tyrosine kinase (rtk) activation stimulates the assembly of intracellular signaling complexes. Meaning a particular ligand may bind to a copy of itself in such a way as to create a dimer/heterodimer which will bring together two potentially slightly different receptor tyrosine kinase molecules to facilitate signaling. Cross phosphorylation means right phosphorylates left and vice- versa. Attenuated by protein tyrosine phophatases facilitators that lead to the removal of these phosphates and disassembly of these complexes, and also attenuated by internalization and degradation. These receptors can be taken up from the membrane.
