Boston, Mass. (Aug. 19, 2011)Researchers at Harvard Medical School have discovered that structural elements in the cell play a crucial role in organizing the motion of cell-surface receptors, proteins that enable cells to receive signals from other parts of the organism.
This discovery, published in the Aug. 19 issue of the journal Cell, fills a fundamental gap in the understanding of how cells relate to biochemical signals, including pharmaceuticals, and could have profound implications for drug development and the treatment of cancer and other diseases.
The findings are already prompting the design of a new lecture on cell signaling in one basic biochemistry course at HMS.
"We found that the way the receptors are organized in the membrane and the way they move around are controlled by the cytoskeleton," said Khuloud Jaqaman, instructor in the Department of Systems Biology at HMS and first author of the study. This dynamic organization promotes signaling function by encouraging receptors to cluster, even if briefly, she said.
Jaqaman and Gaudenz Danuser, HMS professor of cell biology, working with Sergio Grinstein from the Hospital for Sick Children in Toronto as well as colleagues at the University of Alberta, Edmonton, studied the motion of CD36, a receptor in human macrophages, a type of white blood cell that plays a role in immune response. CD36 detects oxidized LDL (oxLDL), a lipoprotein implicated in atherosclerosis.
Receptors are like the antennas in a cell's communication system with the world outside their membrane. The cytoskeleton, which includes a fine meshwork of actin fibers and an array of radiating microtubules, gives the cell its shape.
Like many receptors, CD36 can't work alone; a group of receptors must cluster together to send a signal into the cell. Until now, very little was known about how those functional groups of receptors formed. The cell and receptors were thought to wait
|Contact: David Cameron|
Harvard Medical School