Keeping plant-cell motors on track

In a growing plant cell, motor proteins called kinesins work as transporters that haul materials built in one part of the cell to the place where they are needed. Now, biologists at Washington University in St. Louis have discovered the molecular brakeman that holds kinesins in check until their cargo is needed.

Heme Channel Found

Heme, a crucial component of the biomachinery that squeezes energy out of food, must be transported across membranes but without exposing its central iron atom to oxidation. Work at Washington University shows how it is done.