Mary Halloran
Professor of Zoology
Ph.D. University of Wisconsin-Madison (1994)
Postdoctoral Research: University of Michigan, 1994-1999
Address: 307 Zoology Research
Telephone: 263-7875
E-mail: mchalloran@wisc.edu
Research Interests:
Axon guidance mechanisms in zebrafish neural development.
Research Fields:
Developmental Genetics
Zebrafish
Neurogenetics
Research Description:
Our research is aimed at
understanding how axons are guided to their targets during development of the
nervous system. Several families of
molecules have been identified that can act as axon guidance cues by either attracting
or repelling the motile growth cone at the tip of the growing axon. There is still relatively little known about
how axonal growth cones are guided in the complex in vivo environment, where
they must integrate multiple cues. We
are investigating the function of guidance molecules in vivo using the
zebrafish embryo as a model system. The
zebrafish is a simple vertebrate with rapidly developing, optically transparent
embryos ideal for visualizing developing axons.
We use genetic and molecular manipulation of potential guidance cues combined
with live imaging of growing axons to determine how guidance cues function in
vivo to control the formation of neural connections.
Another main research area in the
lab is aimed at understanding mechanisms of neural crest cell (NCC) migration,
and in particular the epithelial to mesenchymal transition (EMT) that NCCs
undergo to delaminate from the neuroepithelium and begin migration. EMT is a dramatic process involving major
changes in cell morphology and motility that allow cell migration and formation
of new tissues. EMTs are important for
many developmental processes, and are also co-opted in several pathological
processes, including cancer metastasis.
The mechanisms controlling cell changes during EMT remain poorly
understood. Because a cell’s environment
strongly influences its motility and intracellular signaling, it is extremely
useful to have a model in which we can study these mechanisms while cells
undergo EMT in the natural 3D environment.
We are again taking advantage of the zebrafish model to combine in vivo imaging of NCC behavior during
EMT with manipulation of potential signaling molecules.
Representative Publications:
Andersen, E.A., Asuri, N.S. and Halloran, M.C. 2011. In vivo
imaging of cell behaviors and F-actin reveals LIM-HD transcription factor
regulation of peripheral versus central sensory axon development. Neural Development 6:27.
Clay, M.R. and Halloran, M.C. 2011. Regulation of cell adhesions and motility
during initiation of neural crest migration.
Curr Opinion Neurobiol 21(1):17-22
Clay, M.R. and Halloran, M.C. 2010. Control of neural crest cell behavior and
migration: insights from live imaging. Cell
Adh Migr 4(4):582-590.
Andersen, E., Asuri, N., Clay, M., Halloran, M. 2010. Live
Imaging of Cell Motility and Actin Cytoskeleton of Individual Neurons and
Neural Crest Cells in Zebrafish Embryos. JoVE 36.
http://www.jove.com/index/details.stp?id=1726, doi: 10.3791/1726
Paulus, J.D., Willer, G.B.,
Willer, J.R., Gregg, R.G., and Halloran,
M.C. 2009. Muscle contractions guide Rohon-Beard
peripheral sensory axons. J Neurosci 29:13190-13201.
Sittaramane
V., Sawant A., Wolman M.A., Maves L., Halloran
M.C., Chandrasekhar A. 2009. The cell adhesion molecule Tag1,
transmembrane protein Stbm/Vangl2, and Laminin-alpha1 exhibit genetic
interactions during migration of facial branchiomotor neurons in
zebrafish. Dev Biol 325:363-373.
Berndt,
J.D., Clay, M.R., Langenberg, T., and Halloran,
M.C. 2008. Rho-kinase and myosin II affect dynamic
neural crest cell behaviors during epithelial to mesenchymal transition in
vivo. Dev Biol 324:236-244.
Langenberg,
T., Kahana, A., Wszalek, J.A., and Halloran,
M.C. 2008. The eye organizes neural crest cell
migration. Dev Dyn 237:1645-1652.
Wolman,
M.A., Sittaramane, V.K., Essner, J.J., Yost, H.J., Chandrasekhar, A. and Halloran, M.C. 2008.
Transient axonal glycoprotein-1 (TAG-1) and laminin-a1
regulate dynamic growth cone behaviors and initial axon direction in vivo. Neural Development 3:6.
Wolman,
M.A., Regnery, A.M., Becker, T., Becker, C.G., and Halloran, M.C. 2007. Semaphorin3D
regulates axon-axon interactions by modulating levels of L1CAM. J Neurosci 27:9653-9663.
Berndt, J.D. and Halloran, M.C. 2006. Semaphorin3D promotes cell proliferation and neural crest cell development downstream of TCF in the zebrafish hindbrain. Development. 133:3983-3992.
Sakai, J.A. and Halloran, M.C. 2006. Semaphorin3D guides laterality of retinal ganglion cell projections in zebrafish. Development. 133:1035-1044.
Paulus, J.D. and Halloran, M.C. 2006. Zebrafish bashful/Laminin-a1 mutants exhibit multiple axon guidance defects. Dev Dyn. 235:213-224.
Liu, Y. and Halloran, M.C. 2005. Central and peripheral branches from one neuron are guided differentially by Sema3D and TAG-1. J Neurosci. 25:10556-10563.
Wolman, M.A., Liu, Y., Tawarayama, H., Shoji, W. and Halloran, M.C. 2004. Repulsion and attraction of axons by Sema3D are mediated by different neuropilins in vivo. J Neurosci. 24:8428-8435.
Professor of Zoology
Ph.D. University of Wisconsin-Madison (1994)
Postdoctoral Research: University of Michigan, 1994-1999
Address: 307 Zoology Research
Telephone: 263-7875
E-mail: mchalloran@wisc.edu
Research Interests:
Axon guidance mechanisms in zebrafish neural development.
Research Fields:
Developmental Genetics
Zebrafish
Neurogenetics
Our research is aimed at understanding how axons are guided to their targets during development of the nervous system. Several families of molecules have been identified that can act as axon guidance cues by either attracting or repelling the motile growth cone at the tip of the growing axon. There is still relatively little known about how axonal growth cones are guided in the complex in vivo environment, where they must integrate multiple cues. We are investigating the function of guidance molecules in vivo using the zebrafish embryo as a model system. The zebrafish is a simple vertebrate with rapidly developing, optically transparent embryos ideal for visualizing developing axons. We use genetic and molecular manipulation of potential guidance cues combined with live imaging of growing axons to determine how guidance cues function in vivo to control the formation of neural connections.
Another main research area in the lab is aimed at understanding mechanisms of neural crest cell (NCC) migration, and in particular the epithelial to mesenchymal transition (EMT) that NCCs undergo to delaminate from the neuroepithelium and begin migration. EMT is a dramatic process involving major changes in cell morphology and motility that allow cell migration and formation of new tissues. EMTs are important for many developmental processes, and are also co-opted in several pathological processes, including cancer metastasis. The mechanisms controlling cell changes during EMT remain poorly understood. Because a cell’s environment strongly influences its motility and intracellular signaling, it is extremely useful to have a model in which we can study these mechanisms while cells undergo EMT in the natural 3D environment. We are again taking advantage of the zebrafish model to combine in vivo imaging of NCC behavior during EMT with manipulation of potential signaling molecules.
Andersen, E.A., Asuri, N.S. and Halloran, M.C. 2011. In vivo
imaging of cell behaviors and F-actin reveals LIM-HD transcription factor
regulation of peripheral versus central sensory axon development. Neural Development 6:27.
Clay, M.R. and Halloran, M.C. 2011. Regulation of cell adhesions and motility during initiation of neural crest migration. Curr Opinion Neurobiol 21(1):17-22
Clay, M.R. and Halloran, M.C. 2010. Control of neural crest cell behavior and migration: insights from live imaging. Cell Adh Migr 4(4):582-590.
Andersen, E., Asuri, N., Clay, M., Halloran, M. 2010. Live Imaging of Cell Motility and Actin Cytoskeleton of Individual Neurons and Neural Crest Cells in Zebrafish Embryos. JoVE 36. http://www.jove.com/index/details.stp?id=1726, doi: 10.3791/1726
Paulus, J.D., Willer, G.B., Willer, J.R., Gregg, R.G., and Halloran, M.C. 2009. Muscle contractions guide Rohon-Beard peripheral sensory axons. J Neurosci 29:13190-13201.
Sittaramane V., Sawant A., Wolman M.A., Maves L., Halloran M.C., Chandrasekhar A. 2009. The cell adhesion molecule Tag1, transmembrane protein Stbm/Vangl2, and Laminin-alpha1 exhibit genetic interactions during migration of facial branchiomotor neurons in zebrafish. Dev Biol 325:363-373.
Berndt, J.D., Clay, M.R., Langenberg, T., and Halloran, M.C. 2008. Rho-kinase and myosin II affect dynamic neural crest cell behaviors during epithelial to mesenchymal transition in vivo. Dev Biol 324:236-244.
Langenberg, T., Kahana, A., Wszalek, J.A., and Halloran, M.C. 2008. The eye organizes neural crest cell migration. Dev Dyn 237:1645-1652.
Wolman, M.A., Sittaramane, V.K., Essner, J.J., Yost, H.J., Chandrasekhar, A. and Halloran, M.C. 2008. Transient axonal glycoprotein-1 (TAG-1) and laminin-a1 regulate dynamic growth cone behaviors and initial axon direction in vivo. Neural Development 3:6.
Wolman, M.A., Regnery, A.M., Becker, T., Becker, C.G., and Halloran, M.C. 2007. Semaphorin3D regulates axon-axon interactions by modulating levels of L1CAM. J Neurosci 27:9653-9663.
Berndt, J.D. and Halloran, M.C. 2006. Semaphorin3D promotes cell proliferation and neural crest cell development downstream of TCF in the zebrafish hindbrain. Development. 133:3983-3992.