MCDB 418 Lecture Notes - Lecture 17: Phospholipid, Prostate Cancer, Mdm2

• School: U of M
• Department: Molecular, Cellular and Developmental Biology
• Course: MCDB 418
• Professor: Cunming Duan

Document Summary

Lecture 17: pi3 kinase- akt - tor pathways (pi3ks) are intracellular lipid kinases that phosphorylate 3"-hydroxyl group of phosphoinositides. This reaction leads to activation of many intracellular signaling paths that regulate functions as diverse as cell metabolism, survival and polarity, and vesicle trafficking. Once receptor is activated, it binds to the regulatory subunit, which changes conformation to allow catalytic subunit to work. Activates pi (3,4,5 p3) activates akt foxo (nuclear factor). (increases 2nd messenger) = cell proliferation, cell survival. Pten dephosphorylates pi (3,4,5)p3 to pi (4,5)p2 (decreases 2nd messengers) Pdk1 and pdk2 normally localized in membrane with elevated pip3 levels, akt can bind to pdk1 and pdk2 on 2 parts of akt (1 thr 308 and 1 ser 473); once akt activated it phosphorylates many proteins. Insulin and igf-1 are strongest activator of pi3k pathways. Activation, degree of activation, and temporal (stable vs transient) differ amongst signal molecules.