mTOR Decision-Making System A Molecular System That Makes Decisions Among the thousands of molecular systems operating inside a human cell, few coordinate as many different activities as mTOR. Its name, mechanistic target of rapamycin, makes it sound like simply another enzyme. Technically, mTOR is a protein kinase: it transfers phosphate groups to other proteins and thereby changes their behavior. But describing mTOR merely as a kinase is like describing a brain as a collect

How Molecular Motion Allows Cells to Sense and Communicate About Energy Every living cell must constantly answer the fundamental question whether it has enough energy to grow, or must it conserve resources to survive? The molecule responsible for answering that question is AMPK, the AMP-activated protein kinase. AMPK acts as a cellular energy sensor and regulator that monitors energy levels by responding to changes in the ratios of AMP to ATP and ADP to ATP inside cells. At f