Runner Up: Early orientation

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Science  20 Dec 1996:
Vol. 274, Issue 5295, pp. 1988
DOI: 10.1126/science.274.5295.1988h

The satellite-based Global Positioning System may be a big boon to today's navigators, but it's far outstripped by the sophisticated “biological positioning system” in every developing animal embryo, where each cell learns its exact location relative to other cells in order to give rise to the appropriate organ, tissue, or nerve. This year, researchers gained insight into how cells exchange this information by identifying additional molecules that carry and detect positional signals.

For example, researchers had known for years that members of the “Wnt” and “Hedgehog” families of signaling proteins help developing limbs and organs tell up from down and build repeating body segments in fly embryos. In 1996, experiments in several labs identified the receptor for the fruit fly Wnt family member Wingless as a protein called Drosophila frizzled 2; the receptor for the vertebrate protein Sonic hedgehog was unveiled as a complex including both Patched and Smoothened proteins. These findings will help unmask other molecular parties to these orientation feats. And because signaling pathways are often conserved across a wide range of organisms, including humans, the work could even help lead to treatment for the cancers, such as basal cell carcinoma, that arise when the signals go haywire.


News Stories:

  • W. Roush, “Receptor for Vital Protein Finally Found,” Science, 19 July 1996, p. 309.

  • W. Roush, “Hedgehog's Patterning Call Is Patched Through, Smoothly,” Science, 22 November 1996, p. 1304.

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