New Clues to How Proteins Link Up to Run the Cell

Before each task, the proteins that make up the cell9s biochemical machinery must locate and latch onto the right partners in the congested workspace of the cell. Recently, researchers have been learning how protein elements called binding domains help control this coupling and uncoupling. Work described on page 1325 has for the first time put the so-called WW domain into this select group of domains, which control protein interactions that are turned on and off by signals within the cell. Thus this domain, like the others, may be important in regulating cell activities ranging from division to self-destruction.