The main focus of this research proposal is to elucidate the molecular machinery involved in trafficking of AMPA receptors during both developmental and activity dependent paradigms. This study will further the understanding of how pre synaptic signals can lead to acute as well was as long-term changes in synaptic efficacy. This proposal has the advantage of utilizing a wide range of techniques to address the important questions posed. Using a combination of electrophysiological, biochemical, molecular, and microscopy methods, interactions of the GluR1 AMPA receptor subunit with intracellular synaptic proteins can be implicated as key players in synaptic function. A primary neocortical culture system will be used as a model for a functional neuronal network. Overexpression of the wildtype or mutant fluorescent-tagged AMPA receptor interacting proteins SAP97/hDLG and Protein 4.1 by the Sindbis viral expression system will enable the study of these proteins with regard to their effect on synaptic transmission. The effect of chronic (>24 HR) overexpression of SAP97 and Protein 4.1 will be assessed by measuring AMPA mediated mEPSCs. Also, surface expression of GluR1 will also be measure by biochemical methods after overexpression of these proteins. Finally, using a novel assay for long-term potentiation in cultured neurons overexpressing either normal or mutant forms of SAP97 and Protein 4.1 will be employed to understand the role of these proteins in synaptic plasticity.

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Postdoctoral Individual National Research Service Award (F32)
Project #
5F32NS043071-02
Application #
6640648
Study Section
Special Emphasis Panel (ZRG1-MDCN-1 (01))
Program Officer
Talley, Edmund M
Project Start
2002-05-01
Project End
Budget Start
2003-05-01
Budget End
2004-04-30
Support Year
2
Fiscal Year
2003
Total Cost
$46,420
Indirect Cost
Name
Johns Hopkins University
Department
Neurosciences
Type
Schools of Medicine
DUNS #
001910777
City
Baltimore
State
MD
Country
United States
Zip Code
21218
Rumbaugh, Gavin; Adams, J Paige; Kim, Jee H et al. (2006) SynGAP regulates synaptic strength and mitogen-activated protein kinases in cultured neurons. Proc Natl Acad Sci U S A 103:4344-51
Rumbaugh, Gavin; Sia, Gek-Ming; Garner, Craig C et al. (2003) Synapse-associated protein-97 isoform-specific regulation of surface AMPA receptors and synaptic function in cultured neurons. J Neurosci 23:4567-76