People with celiac disease usually have a certain type of cell surface receptor that helps set off the immune reaction.

FORBES: Gluten-Free Diets: Miracle Or Hype?

Like a key in a lock, EGF binds to a receptor on a cell's surface, sending off a signal to the cell to divide, grow and die.

FORBES: A Homegrown Pipeline

HINT, crops up in 11 different genes for receptor proteins that sit on a cell's surface waiting for messenger molecules from other cells.

ECONOMIST: The first complete DNA sequence of an animal is now in the bag

Even more surprisingly, they found that each receptor, located on the surface of a particular cell, is unique, and when activated by an odorant, triggers the cell to send an electrical signal to the brain.

ECONOMIST: The Nobel prizes

Now entering human trials, it blocks a newly discovered receptor known as H3, the third in a family of crucial cell-surface proteins that receive messages from the hormone histamine.

FORBES: J&J An unfinished symphony

This will be useful because the location and activity of receptor proteins on surface membranes can be a matter of life and death for a cell or a virus.

ECONOMIST: Microscopy