Nobel Prize in medicine honors discoveries on how cells move ‘cargo’ http://www.pbs.org/newshour/rundown/2013/10/nobel-prize-in-medicine-honors-discoveries- on-how-cells-move-cargo.html

By Rebecca Jacobson

The 2013 Nobel Prize in Medicine is shared by three American scientists for their work on how cells move molecular "cargo" on time, which plays a major role in immune diseases, neurological diseases and diabetes.

Cells manufacture neurotransmitters, hormones and enzymes, which are packaged in bubbles called vesicles and transported within the cell or exported to another cell. It's a transportation system that requires precise timing and accurate loading and unloading. When cargo piles up or is delivered late, it can contribute to disease. For example, if cells don't deliver insulin to the bloodstream on time, it can result in diabetes. Newly named Nobel Laureates James Rothman, Randy Schekman and Thomas Sudhof discovered how that delivery system works.

Randy Schekman, professor of molecular and cell biology at University of California Berkeley, discovered the mutated genes which cause cargo "pile-ups" within a cell, and identified three classes of genes that control different aspects of the cell´s transport system. James Rothman, professor of cell biology at Yale University, discovered that when vesicles find the right loading dock for its cargo, they attach to their target like a zipper. It requires an exact match between vesicle and target, ensuring that molecules were delivered to the right place.

Rothman and Schekman's research mapped the transport system, but timing is crucial. Thomas Südhof, professor of cell biology at Stanford University, built on Rothman and Schekman's research. He found that in neurons, an influx of calcium cued the vesicles to release their content at the right time, resulting in synaptic transmissions in the brain.