Within the intricate machinery of every living cell, a question is perpetually being asked: is it time to grow? Researchers at KAIST and Yonsei University have now answered part of that question, identifying the precise molecular messenger — a protein called LARS1 — that translates the presence of nutrients into a command for cellular growth. By mapping how LARS1 breaks free from its anchoring complex and activates mTORC1, the cell's master growth switch, the team has illuminated a mechanism that cancer exploits and that medicine might one day learn to intercept with greater precision and less