10/11: Work that won Nobel prize a basis for research
Work that won Nobel prize a basis for research
By Maggie Fox, Health and Science Correspondent
WASHINGTON, Oct 11 (Reuters) - The work that won German-born scientist Guenter Blobel the Nobel prize in Medicine is now used as the basis for a range of medical research, from developing new treatments for cystic fibrosis to searching for drugs based on the body's own genes.
The prize honors his work in identifying the signals that help proteins find their way around cells. Proteins do all the work of cells, and are the direct product of all genes.
Researchers who have worked with Blobel, or who have used his work as a basis for their own experiments, say understanding these signals forms a vital basis for knowing how a cell works. Blobel describes the signals as the body's own postal system.
"It's very fundamental research," Dr. David Sabatini, chair of the Department of Cell Biology at the New York University School of Medicine, said in a telephone interview. "Proteins have to be addressed someplace within the cell."
Many biotechnology companies use or even modify these signals to make their products, which are based on the body's own compounds, said Sabatini, who worked with Blobel early in the prizewinner's career.
"Proteins made by biotech companies such as hormones or growth factors, et cetera, contain these signals," he said.
One example is Human Genome Sciences Inc. <HGSI.O>, which searches through the human genome, the collection of all genes, looking for genes that control potentially useful proteins.
Dr. William Haseltine, chief executive officer of HGS, said the signals identified by Blobel are more than just addresses -- they make sure that proteins get to where they are supposed to be. "It's the pore that our proteins use to get the surface," he said.
Haseltine's company is working on a range of proteins, from the VEGF protein which helps control the growth of blood vessels -- useful in treating both cancer and heart disease -- to a protein used to rev up immune cells.
"As a protein is made, it is extruded through the pore into the (cell's) inner membrane like a spaghetti," Haseltine said.
Then it either stays in the cell membrane -- perhaps to act as a receptor, or a kind of doorway, into the cell -- or it is sent out to other cells. Blobel's signal controls this.
Examples of well-known compounds that use this signal are growth hormone and insulin.
Both use proteins that stay on the surface of the cell and act as receptors. The circulating hormones latch on to them to do their work -- controlling growth in the case of growth hormone and controlling the metabolism of fats and sugars in the case of insulin.
When this goes wrong, disease can result. The example given by Blobel is cystic fibrosis, the most common genetically caused disease among people of European descent.
In CF, a single gene is mutated. The protein this gene controls, the cystic fibrosis transmembrane receptor (CFTR), fails to work properly.
Normally it creates a channel, or pore, for chloride to go in and out of a cell. But in CF this channel stays closed. Abnormal salt concentrations build up, making the lungs, intestines and pancreases of CF patients clog up.
"The protein ... cannot complete its journey from an intracellular membrane," Blobel told a news conference.
"The protein is perfectly functioning but it doesn't go to the right address."
17:12 10-11-99 |
