BIO 314 Lecture Notes - Lecture 5: Metastasis, Generation Time, Cell Membrane
Document Summary
Chapter 6: cytoplasmic signaling: understand the response of a quiescent cell to mitogens. Resting cells in the g1 phase that are given serum show a significant change in gene transcription. Abundance of mrna and stability of mrna is affected by introduction of mitogens. This occurs without the protein synthesis; everything already exists in the cell: know what sh1, sh2, and sh3-domain proteins are, and the roles they play in ras activation. Ligand binds to receptors which are sh1 proteins. Sos, the guanine exchange factor that activates ras, can be bound by sh3 proteins to the sh2 proteins, which allows for ras to be switched on: know the three effector pathways downstream of ras. This is a series of kinases that get activated by mitogens, ending with activation of response molecules that increase proliferation; reactivates chromatin, turns on protein translation, increases transcription. This attracts cytosolic proteins to the membrane, such as akt/pkb; which boosts survival, proliferation, and reduces apoptosis.
