The protein complex is mTORC1, which regulates cell growth and metabolism. Immunologists found mTORC1 acts in response to cues from in and around developing T cells and intersects with metabolic activity, to influence whether the cells become conventional or unconventional T cells. To their surprise, researchers found that disrupting mTORC1 led to metabolic changes that favored development of unconventional T cells at the expense of conventional T cells.