BIO315H5 Lecture Notes - Lecture 5: Cytokine, Rhoa, Gtpase
Document Summary
Lecture 5: mechanisms of signaling through enzyme-coupled receptors (chapter 15, pp. Ras: family of related proteins which is universally expressed in all cell lineages and organs. All ras protein family members belong to a class of protein called small gtpase, and are involved in transmitting signals within cells. Ras-gefs: stimulate the dissociation of gdp and the subsequent uptake of. Ras-gaps: increase the rate of hydrolysis of bound gtp by ras, thereby inactivating ras. an active state: rtks activate ras by indirect coupling of the receptor to a ras-gef, driving ras into. Sevenless signaling (ras signalling in fly development: an rtk called sevenless (sev) is required for the formation of a photoreceptor cell called r7. Ras signaling: tyrosine phosphorylations and ras activation are usually short-lived due to the actions of tyrosine-specific protein phosphatases and gaps, respectively, these signals are converted to longer-lasting signals that may ultimately impact gene expression.
