A Long-Range Recruitment Mechanism for mTORC2 Phosphorylation of Akt

Study of the phosphorylation of human Akt1 (Akt) by mTOR complex 2 (mTORC2) in vitro. Akt was prepared by semi-synthesis, resulting in a non-phosphorylated C-tail, allowing unbiased study of the sites phosphorylated by mTORC2. Because enzymologic data showed that the canonical hydrophobic motif residue, Akt Ser473, accounts for only a portion of the phosphorylation, and because the C-tail has at least 4 known phospho sites (Ser473, Ser475, Ser477, Thr479) and numerous other candidates, we sought to determine the catalog of sites on Akt that mTORC2 phosphorylates.