The mTORC1 complex promotes protein translation and cell growth, whereas mTORC2 promotes survival. The Tel2 and Tt1 proteins belong to both complexes. Bassermann and colleagues demonstrate that following growth-factor deprivation, casein kinase 2 mediates phosphorylation of Tel2 and Tt1, specifically in the mTORC1 complex, to target them for degradation by the SCFFbxo9 ubiquitin ligase. This mechanism inactivates mTORC1 and activates mTORC2 and Akt signalling to promote survival of multiple myeloma cells.
- Vanesa Fernández-Sáiz
- Bianca-Sabrina Targosz
- Florian Bassermann