Like modern-day high performance machines, cells are constantly monitoring signals in their environment in order to "decide" on a course of action such as growth or movement. The signals are transmitted and processed by groups of proteins linked in specific circuits. Focusing on a protein that directs cell movement, the researchers were able to substitute key parts of the protein so that the reaction driving cell movement came under the control of new signals. Their study demonstrates that the signaling proteins are made of highly interchangeable "modules," the scientists report. This interchangeability may allow engineering of cells with new decision-making circuits, the scientists say.

"Signaling proteins and other molecules in cells talk to one another by touching or binding one another," says Wendell Lim, PhD, UCSF associate professor of cellular and molecular pharmacology. "When you look at different signaling systems in cells, you can recognize many of the same components the same subfragments of proteins linked together in different ways. We showed that the components are modular the equivalent of electronic components. By mixing and matching components we can generate novel and diverse circuits and behavior.

"It may be possible to use this technology to engineer cells that can act as cheap and robust sensors or computers, for example. You might be able to engineer cells that act like an artificial pancreas. In principle it may be possible to combat cancer by designing a signaling switch that promotes cell death only when triggered by proteins found in tumor cells."

Lim is senior author on a paper reporting this research in the September 26 issue of the journal
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Contact: Wallace Ravven
wravven@pubaff.ucsf.edu
415-476-2557
University of California - San Francisco
25-Sep-2003