Cells make their largest decisions at a few regulatory hubs: AMPK, which senses energy; mTOR, which decides whether to grow; p53, which guards the genome; and NF-κB, which coordinates inflammation and immunity. These hubs regulate one another in a web rather than a chain of command, but they have something in common. AMPK reads the ratio of AMP and ADP to ATP directly. mTOR checks the supply of S-adenosylmethionine through a dedicated sensor. p53 carries acetyl, methyl, ubiqu

Unfolded parts of NF-κB and IκBα run the cell's inflammatory switch The textbook story of the transcription factor NF-κB is about two folded proteins that form a pair and trigger specific region of DNA. NF-kB is most often used to refer to the very common version of NF-kB that is a pair of molecules, p50 paring with p65, from the family of 5 NF-kB molecules that form many different pairs. The name NF-kB, Nuclear Factor kappa beta, comes from the immune cell where it was first

Every time you cut your finger, catch a cold, or feel the ache of an inflamed joint, a family of proteins called NF-κB is making decisions inside your cells. It decides whether a cell should sound an alarm, which alarm to sound, how loudly, and for how long. In a human immune cell, that decision passes through dozens of proteins arranged in layered circuits. The system did not begin that way. It began with one molecule that could do little more than bind DNA, and it acquired