B.A., 1981, Johns Hopkins University.
Ph.D., 1991, California Institute of Technology, Jerry Pine's lab.
Postdoc, 1991-1995, University of California San Diego, Bill Harris's lab.
Postdoc, 1996-1997, Max Planck Institute for Developmental Biology, Tuebingen, Germany, Friedrich Bonhoeffer's lab.
My primary interest is in axon pathfinding: how does the growth cone smell its environment, then make and execute pathfinding decisions? The lab is working on the known retinotectal pathfinding mutants, characterizing novel growth cone guidance receptors and signal transduction molecules, and developing imaging techniques for observing individual growth cones in vivo.
We showed that the astray
mutant has a defect in a zebrafish Roundabout homolog, and are continuing to study intensively the cell-biological function of Slit-Robo signaling. We have also cloned several of the topography mutants. In particular, we have found that boxer
are defective in heparan sulfate proteoglycan synthesis, and are continuing to study how the lack of HSPGs leads to defects in optic tract sorting. Most recently, we found that nevermind
is mutant in the cyfip2
gene, which encodes a protein in the WAVE complex that also binds to FMR1 family members, implicating one or both of these pathways in axon sorting in the optic tract and guidance on the tectum.
More recently we have broadened our interests to include vascular guidance (specifically, the role of Netrin1a signaling), dorsoventral patterning of the eye (Bmp and Wnt signaling), and eye morphogenesis (complex cell movements and their interplay with patterning).
I am also very interested in developing resources for the community, including DNA reagents, software, and fish. The Tol2kit
is a set of plasmids for multisite Gateway cloning of Tol2 expression constructs, which provides a platform for facile exchange of plasmid constructs between labs. We are collaborating with computer scientists at Utah to develop new 3D visualization software (FluoRender
), as well as software for tracking cell movements in 4D datasets (LongTracker).
We are currently conducting a Gal4 enhancer trap screen, for which we are documenting expression patterns by widefield and confocal microscopy; lines will be distributed through ZIRC.
Chondroitin sulfate disrupts axon pathfinding in the optic tract and alters growth cone dynamics. Walz A, Anderson RB, Irie A, Chien CB, Holt CE. J Neurobiol. 53(3):330-42 (2002)
'Why does the growth cone cross the road? (minireview)' CB Chien. Neuron 20:3-6 (1998).
'PY in the fly: receptor-like tyrosine phosphatases in axonal pathfinding (minireview).' CB Chien. Neuron 16:1065-1068 (1996).
'Signal transduction in vertebrate growth cones navigating in vivo.' CB Chien and WA Harris. Perspect Dev Neurobiol, 4: 253-266 (1996).
'Embryonic taste buds develop in the absence of innervation.' LA Barlow, CB Chien, and RG Northcutt. Development 122: 1103-1111 (1996).
'Absence of topography in precociously innervated tecta.' CB Chien, EM Cornel, and CE Holt. Development 121: 2621-2631 (1995).
'Axonal guidance from retina to tectum in embryonic Xenopus.' CB Chien and WA Harris. Curr Top Dev Biol, 29: 135-169 (1994).
'Navigational errors made by growth cones without filopodia in the embryonic Xenopus brain.' CB Chien, DE Rosenthal, WA Harris, and CE Holt. Neuron 11: 237-251 (1993).