The Nobel Prize for Medicine has this year been jointly awarded to three top scientists for unraveling the mystery of cell transport systems. Separate discoveries made over the past 40 years by American scientists James Rothman and Randy Schekman and German born Thomas Südhof have revealed how cells deliver messages in a targeted and timely fashion.

Cells are complicated. Each second, a cell delivers thousands of messages internally by ‘molecular post’ to other parts of the cell, or exports them to communicate with other cells. This constant conversation is vital for our bodies to work properly. These molecular messages, carried in tiny bubbles called vesicles, must be delivered to the right place at the right time. Failure to do so can result in disease. For example, failure to release the hormone insulin from our pancreas results in diabetes, and delayed release of neurotransmitters prevents the relaying of messages from our brain, leading to neurological disorders. Each of the three winners has contributed to our understanding of this communication process in different ways.

In the 1970s, Randy Schekman ¹ was using yeast to identify the genes important for relaying the messages stored in vesicles. He noticed cells that had problems with their transport system and could see that vesicles were piling up in the cell and not being released in the proper way. In the following years, James Rothman ² added to these findings. In cells similar to our own, he revealed how messages could be targeted to specific compartments in the cell called organelles. It appeared that patterns of proteins scattering outside the vesicle could bind like a zipper only to specific patterns on the correct compartment, allowing specific delivery, just like an address. Thomas Südhof ³ was interested in the messages passed between neurons. He discovered how the delivery of neurotransmitters is perfectly timed, allowing our brain to give correctly timed instructions to our body.

Together, their work has revealed how cells send messages through a ‘molecular post’ system. We now have a better understanding of how the messages carried by this system can be delivered to specific addresses with precise timing, both within and outside the cell.

1. Novick P, Schekman R: Secretion and cell-surface growth are blocked in a temperature-sensitive mutant of Saccharomyces cerevisiae. Proc Natl Acad Sci USA 1979 
2. Balch WE, Dunphy WG, Braell WA, Rothman JE: Reconstitution of the transport of protein between successive compartments of the Golgi measured by the coupled incorporation of N-acetylglucosamine. Cell 1984 
3. Perin MS, Fried VA, Mignery GA, Jahn R, Südhof TC: Phospholipid binding by a synaptic vesicle protein homologous to the regulatory region of protein kinase C. Nature 1990