Ava Udvadia Assistant Professor B.S. University of Michigan, Cell and Molecular Biology, 1989 Ph.D. Duke University, Molecular Cancer Biology, 1995 Post-doctoral Fellow Duke University, Neuroscience, 1996-2001	Lab: WATER Institute, 248 Phone:   WATER Institute 414-382-1750   Lapham 414-229-3404 FAX: 414-382-1705 Email: audvadia@uwm.edu
Developmental and Molecular Neuroscience

Research Interests

My main research interests center on understanding the molecular and cellular mechanisms of central nervous system (CNS) development and regeneration. Currently I am focusing on the regulation of axon growth using two complementary approaches: 1. analysis of the signaling pathways that regulate the synthesis and post-translational modification of GAP-43, a protein known to be important in developmental and regenerative axon growth, and 2. identification of novel genes that are selectively expressed in neurons undergoing axon growth at different life stages using subtractive hybridization. I am using the zebrafish as a model organism to address the following questions regarding nervous system development and regeneration: 1) how do mechanisms regulating axon growth differ between the developing and regenerating nervous system? 2) what are the differences between neurons or nervous systems that are capable of regeneration and those that are not? 3) how do environmental stressors impact the developing and regenerating nervous system? 4) how do subtle changes in early neuronal connectivity correlate with capacity to learn? Axon growth potential is regulated in three distinct phases: (1) Activation of axon growth in newly differentiated neurons; (2) Down-regulation of axon growth potential in maturing neurons where synaptic connections have matured and stabilized; and (3) Stimulation of axon re-growth following damage to mature neurons. While the first two phases are obligatory developmental steps in the formation of a functioning nervous system, the third phase occurs in a species-, neuronal class- and injury-specific manner. For example, the peripheral nervous systems (PNS) of all animals have a remarkable potential for regenerative axon growth. However, the capacity for CNS regeneration can differ between amniotes (mammals and birds) and anamniotes (fish and amphibians). With a few notable exceptions, regenerative axon growth in adult mammals and birds is not observed under normal circumstances. Conversely, in fish and amphibians, functional repair of the adult CNS occurs routinely. This difference is due to factors both intrinsic and extrinsic to the neurons. My work focuses on intrinsic factors that influence axon growth. Research in Progress       Identification of gene regulatory elements within genes that are targeted by axon growth signaling pathways during development and regeneration       Discovery and characterization of gene transcripts and their encoded products that are enriched in developing and regenerating neurons       Effects of GAP-43 phosphorylation on axon growth and plasticity in developing and adult zebrafish.       Effects of aquatic contaminants on gene regulation in the developing vertebrate nervous system

Selected Publications

Ava J. Udvadia, 3.6 kb genomic sequence from Takifugu capable of promoting axon growth associated gene expression in developing and regenerating zebrafish neurons. Manuscript submitted. Brandon W. Kusik, Michael J. Carvan III, Ava J. Udvadia. Detection of Mercury in Aquatic Environments using EPRE reporter zebrafish. Manuscript submitted. Ava J. Udvadia. Differences in distal cis-regulatory sequences of gap43 gene between fish, birds and mammals correlate with CNS regenerative ability. Manuscript in preparation. Angela Schmoldt, Dena Hammond, Jennifer Forecki, and Ava J. Udvadia. Identification and characterization of novel genes expressed during vertebrate axon growth. Manuscript in preparation. Linney, E., and Udvadia, A. J., 2004. Construction and detection of fluorescent germ-line transgenic zebrafish. In "Methods in Molecular Medicine" (H. Schatten, Ed.), Vol. 254, Germ Cell Protocols: Molecular Embryo Analysis, Live Imaging, Transgenesis, and Cloning, pp. 271-288. Humana Press Inc., Totowa, NJ. Ava J. Udvadia and Elwood Linney, 2003. Windows into Development: Historic, Current and Future Perspectives on Transgenic Zebrafish. Developmental Biology, 256: 1-17. Ava J. Udvadia, Reinhard W. Köster, and J. H. Pate Skene, 2001. GAP-43 Promoter Elements in Transgenic Zebrafish Reveal a Difference in Signals for Axon Growth During CNS Development and Regeneration. Development, 128: 1175-1182.