My career goal is to understand the mechanisms of neuronal compartmentalization and how this process contributes to nervous system function and to the pathogenesis of neurological disorders. I will pursue this goal by working in an academic institution as an independent investigator. During my postdoctoral training in the laboratory of Dr. Yuh Nung Jan at UCSF, I have been using Drosophila PNS neurons as a model system to study the mechanisms that differentiate the development of dendrite from axon, two major compartments of a neuron. This training complements my doctoral training in vertebrate neurobiology. I plan to combine the strength of Drosophila (in vivo and superb genetics) and cultured rat hippocampal neurons (wellcharacterized cell biology) to study neuronal compartmentalization. The objective of this research is to examine the roles of the secretory pathway in differentiating dendrite and axon development. From a genetic screen in Drosophila, we isolated several mutants (dar mutants) with reduced dendritic arbors but normal axons. Dar2, 3, and 6 regulate the secretory pathway, suggesting that this pathway differentiates dendritic and axonal growth. I propose two aims. First, I will determine cell biological mechanisms through which the secretory pathway differentially controls dendritic and axonal growth. New techniques will be developed to complement existing ones to identify such mechanisms. Membrane traffic through the secretory pathway will be monitored in live wild-type and mutant Drosophila embryos/larvae and cultured hippocampal neurons. Second, I will identify and characterize genes that control the differential development of dendrites and axons by regulating key players of the secretory pathway. Dar7 (genetically interacts with dar2 and 3), darl (genetic interaction untested), and Trailer Hitch (regulates the secretory pathway) will be studied. Their mammalian homologs will be examined in cultured neurons to determine if the mechanisms are conserved in mammals. This research will provide much-needed information for understanding the causes of neurological disorders characterized by preferential damage to dendrites (e.g., Rett's syndrome) or by defective Golgi function (e.g., amyotrophic lateral sclerosis). Such information will also allow the design of therapeutic approaches.

Agency
National Institute of Health (NIH)
Institute
National Institute of Mental Health (NIMH)
Type
Research Transition Award (R00)
Project #
4R00MH080599-03
Application #
7675626
Study Section
Special Emphasis Panel (NSS)
Program Officer
Panchision, David M
Project Start
2006-09-25
Project End
2011-06-30
Budget Start
2008-09-15
Budget End
2009-06-30
Support Year
3
Fiscal Year
2008
Total Cost
$249,000
Indirect Cost
Name
University of Michigan Ann Arbor
Department
Anatomy/Cell Biology
Type
Schools of Medicine
DUNS #
073133571
City
Ann Arbor
State
MI
Country
United States
Zip Code
48109
Mishra, Bibhudatta; Ghannad-Rezaie, Mostafa; Li, Jiaxing et al. (2014) Using microfluidics chips for live imaging and study of injury responses in Drosophila larvae. J Vis Exp :e50998
Wang, Xin; Kim, Jung Hwan; Bazzi, Mouna et al. (2013) Bimodal control of dendritic and axonal growth by the dual leucine zipper kinase pathway. PLoS Biol 11:e1001572
Kim, Jung Hwan; Wang, Xin; Coolon, Rosemary et al. (2013) Dscam expression levels determine presynaptic arbor sizes in Drosophila sensory neurons. Neuron 78:827-38
Caceres, Alfredo; Ye, Bing; Dotti, Carlos G (2012) Neuronal polarity: demarcation, growth and commitment. Curr Opin Cell Biol 24:547-53
Ye, Bing; Kim, Jung Hwan; Yang, Limin et al. (2011) Differential regulation of dendritic and axonal development by the novel Krüppel-like factor Dar1. J Neurosci 31:3309-19