"Having the sea urchin genome is almost an epiphany. I can see the genes, and it's very exciting," added Ettensohn, who has been studying the sea urchin as a model of development for more than 25 years. Specifically, he focuses on the vast network of proteins needed for these animals to form skeletons through biomineralization.

"If we understand how sea urchins build their skeletons, we can learn more about how we build our skeletons," Ettensohn said. "Additionally, understanding how natural systems build skeletons can help us mimic that in the design of materials to treat bone disease and injury in humans."

As part of the Sea Urchin Genome Sequencing Consortium, Ettensohn contributed 51,000 cDNAs -- about one-third of the total genomic material critical for the assembly of the genome and for the accurate prediction of where genes lie within the DNA sequence.

The Ettensohn lab was also one of 15 labs to annotate sets of genes that comprise the sea urchin genome. Initially, computers assembled the genome sequence and predicted the sea urchin genes. These predictions were then verified by scientists in the lab. Ettensohn annotated the genes involved in biomineralization, the process by which sea urchins form their embryonic skeletons. His work resulted in a comprehensive catalog of all the genes that are actually being used by the embryonic cells responsible for building the skeleton, including when and where the genes are expressed in the embryo.

In the sea urchin embryo, specialized cells produce proteins that mix with mineral crystals, thereby regulating the growth and shape of the emerging skeleton, just as in humans. But having the sea urchin genome has revealed a provocative discovery: many of the biomineralization proteins, especially those that control
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Contact: Lauren Ward
wardle@andrew.cmu.edu
412-268-7761
Carnegie Mellon University
9-Nov-2006