We are using genetics and molecular biology to discover and analyze the spatial cues and navigational programs that guide complex migrations during development. Each cell or axon migration comprises a series of attachments and detachments of motile cells to stationary cells, or extracellular matrix, which support and guide their movements. Mutants with abnormal cell or axonal trajectories can identify genes involved in the generation or detection of guidance cues. Because of its cellular simplicity and excellent genetics, the free-living nematode C. elegans has proved useful for mutant analyses of developmental processes, including migrations, that depend on interactions between distinct cell types. Nearly 30 genes affecting cell migrations or axon outgrowth have been discovered to date.
Some mig genes affect specific navigational steps while others are strikingly pleiotropic.
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