Two new faculty members at the University of California, Davis, Hwai-Jong Cheng and Elva D. Diaz, have won prestigious Alfred P. Sloan Research Fellowships worth $40,000 each over two years.

Cheng, an assistant professor at the Center for Neuroscience and the Section of Neurobiology, Physiology and Behavior, and Diaz, an assistant professor in the department of pharmacology and toxicology who is also affiliated with the center, both study how connections form between nerve cells.

In the developing brain, axons grow out from nerve cells and make connections to other nerve cells. Cheng is interested in how axons are guided to their target and the molecules that regulate the process. His laboratory uses mice in which genes for specific guidance molecules have been deleted or "knocked out" to discover what those molecules do.

One aspect of Cheng's work is to investigate "axonal pruning." Once the connections between nerves have been made, excessive branches have to be removed -- pruned -- away. Mistakes in axonal pruning might be responsible for a rare condition called synesthesia or "colored hearing" in which people perceive sound as colors, Cheng said.

Diaz is using genomic techniques to study which genes are turned on or off during neural development. Her laboratory uses DNA microarrays to look at thousands of genes at the same time, then focuses in on individual genes and proteins to work out how they act at different stages of development.

"With a combination of molecular and genomic approaches, we can identify patterns of gene expression that underlie specific developmental events such as synapse formation," she said.

Knowledge of how brain and nerve tissue develops normally could have relevance for understanding neurodevelopmental disorders such as autism, Diaz said.

Cheng gained his M.D. from the National Taiwan University in 1989 and his Ph.D. from Harvard University in 1995. He then returned to National Taiwan University for two years to complete his clinical residency in pathology. From 1997 to 2001 he was a postdoctoral researcher at the Howard Hughes Medical Institute at UC San Francisco and at Stanford University. He joined UC Davis in October 2002.

Diaz received a bachelor's degree in biochemistry from Harvard University in 1993 and her Ph.D. from Stanford University in 1999. She carried out her postdoctoral research at UC Berkeley from 1999 until she joined UC Davis in July 2003.

The Sloan Foundation awarded 116 fellowships this year to outstanding young scientists in the fields of physics, chemistry, mathematics, computational or evolutionary molecular biology, neuroscience, economics or computer science. The fellowships are intended to provide support to young researchers at the point in their careers when they are establishing independent research projects. Since the program began in 1955, 28 Sloan fellows have gone on to win Nobel prizes.