[
Science,
1985]
The biologists who investigate nature's deepest and longest-running mystery often use the term fate map to describe the startling transformations that lie in store for the fertilized egg. It is one of the more venerable terms in embryology, and one of the most appropriate, too, for destiny and geography indeed intersect within the magnificent speck of DNA and cytoplasm that is an egg on the edge of becoming a organism. In this one cell, the entire genetic bill of lading for an animal, be it fruit fly or human, is stored, waiting to unfold with miraculous precision. It is that process of life unfurling-of cells becoming brain or backbone, of genes selectively flashing on and herding cells toward their certain fates, of tissues aggregating and differentiating toward ever more specific tasks-that both confounds and as surely delights developmental biologists.
[
Science,
2002]
As any homeowner knows, timely maintenance is vital for keeping a building functioning properly after construction is finished. The same is evidently true for the complex architecture of the nervous system - at least in the roundworm. On page 686, neuroscientists Oliver Hobert, Oscar Aurelio, and David Hall describe a new family of proteins that help keep the wiring of the worm's nervous system tangle free.
[
Nature,
1994]
On page 32 of this issue, a joint team from the Genome Sequencing Center (St. Louis, USA) and the newly founded Sanger Centre (Hinxton Hall, Cambridge, UK) report a contiguous sequence of over two megabases from chromosome III of the nematode worm, Caenorhabditis elegans. This is the longest contiguous DNA sequence yet determined, and it prompts rumination on how far we have come in the sequencing enterprise, and on how far - and where - we have