All cells are surrounded by protective, fatty membranes.In the cell membrane there are thousands of membrane proteins that transport nutritional substances, ions, and water through the membrane. Membrane proteins are also necessary for cells to recognize each other in the body and for a nervous system, for example, to be formed.
Researchers at Stockholm University report in Nature that they have now managed to reveal the "molecular code" that governs the insertion of proteins in the cell membrane.
About 25 percent of all proteins in a cell are found in the cell membrane. Since they regulate all communication between the inside of the cell and the surrounding environment, many membrane proteins are crucial to the life of the cell. Disruptions of their functions often lead to diseases of various kinds. For the drug industry, membrane proteins are high priority "drug targets."
To be suitable for deployment in the fatty cell membrane, all membrane proteins must be lipophiles ("fat-lovers"). All cells have special machinery for producing and dealing with "fatty" proteins and to see to it that they are deployed in proper manner in the cell membrane. The Stockholm University scientists have developed a method for the detailed study of the properties of a membrane protein that are required for it to be recognized by the cell machinery.
A couple of years ago the research team published a first article in Nature in which they managed to show that there is a "fat threshold" that determines whether a protein can be deployed to a membrane or not. In this new study they have fully revealed the molecular code that governs the structure of membrane proteins.
"Now that we have deciphered the code, we can determine with a high degree of certainty which parts of a protein will fasten in the membrane." says Gunnar von Heijne.
This new knowledge will help researchers all over the world who are trying to understand more about the cell and its membrane, not least in the drug industry.
"Interest in membrane proteins is at a peak right now, and our findings can be key pieces of the puzzle for pharmaceutical chemists working with drug design, for example," says Gunnar von Hejne.
Article: "Molecular code for transmembrane-helix recognition by the Sec61 translocon", Nature, December 13, 2007.