BIO315H5 Lecture Notes - Lecture 2: Endocytosis, Phosphoinositide 3-Kinase, Sh2 Domain
Document Summary
Heterotrimeric 3 diff subunits (alpha, beta, gamma) that are activated by. Monomeric gtpases/g protein only have 1 subunit and not directly activated by gpcr: ex. Regulation of monomeric gtpases: when there is a signal, gef gets activated, it displaces gdp and allows gtp to bind- exchange factor. In heterotrimeric proteins, the gef is actually the receptor: if the gpcr gets activated, it acts as the gef, the g protein itself has gtpase activity. 3 types: gef promotes the activate state of the g protein, gap promotes the inactive state, gdi lock the inactive g protein by preventing gdp from being released. Signal integration, response specificity and the role of coincidence detectors : signal integration allows cell to mount an appropriate responses, ie,. Combination of responses: coincidence detectors, ex. if have a signal from molecule a, activates receptor, not do anything, unless a signal from b causes phosphorylation at the diff site.
