March 8, 2001—Researchers have developed a powerful screening method to identify genes that produce proteins that guide the wiring of the trillions of connections in the mammalian brain. The technique enables scientists to identify new genes and to determine which genes are responsible for defects in brain wiring that are observed during development. The scientists believe that this technique is likely to accelerate the discovery of new molecules involved in axon guidance.

Neurons wire themselves into networks by extending cable-like axons that grow toward specific targets in the nervous system. An axon’s path toward a target neuron is steered by growth cones in the tip of the axon that receive cues about the best path to follow from chemical attractants and repellents secreted by cells in the nervous system. These attractants and repellents are collectively called axon guidance molecules.

In an article published in the March 8, 2001, issue of Nature, researchers led by Howard Hughes Medical Institute investigator Marc Tessier-Lavigne at the University of California, San Francisco and William C. Skarnes at the University of California, Berkeley, unveil their new technique and discuss some early applications of the method.

The new “gene-trapping” technique could liberate scientists from laborious genetic screens and biochemical approaches that are currently used to identify new molecules involved in axon guidance, t
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Contact: Jim Keeley
keeleyj@hhmi.org
301-215-8858
Howard Hughes Medical Institute
7-Mar-2001