Neuronal cell death in the developing nervous system probably results from activation of an endogenous """"""""death program"""""""". There is considerable interest in identifying cell death genes in vertebrates; however, at present none have been isolated. An in vitro model system has been developed to characterize cellular and molecular events in neuronal cell death. It consists of a subline of PC12 cells that undergoes RNA and protein synthesis-dependent cell death following removal of NGF. Using this model system, 6 cDNAs have been isolated that are un-regulated in dying cells. Characterizing these cDNAs and identifying additional genes activated in dying cells is the major focus of the proposed studies. This information should improve our understanding of mechanisms responsible for neuronal cell death. The long term goal of these studies is to understand cellular and molecular mechanisms involved in neuronal cell death with the hope of identifying ways of blocking cell death following trauma or in neurodegenerative diseases.
The Specific Aim of the proposal are: 1) to use biochemical, molecular and immunological techniques to characterize the 6 cDNAs already isolated from dying cells, 2) to determine if modulating levels of their proteins affects cell survival and/or cellular processes, and 3) to identify low abundance, possibly regulatory genes, induced at early times after removing NGF by making and screening a subtracted cDNA library. Understanding why and how neurons die should have a tremendous impact on both basic and clinical neuroscience. It is obvious that the present study can not address the large number of questions dealing with why neurons die during development, aging, trauma, or neurodegenerative diseases; however, the proposed experiments represent an initial endeavor to identify biochemical and molecular events responsible for neurons dying following loss of trophic support. A fundamental knowledge of genes that control cell death and the molecular cascade of events resulting in neuronal cell death is important for understanding a variety of developmental events as well as providing potentially important information for pathophysiologies associated with the normal aging process or neurodegenerative diseases.

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Research Project (R01)
Project #
1R01NS032465-01
Application #
2270684
Study Section
Neurology C Study Section (NEUC)
Project Start
1994-01-01
Project End
1997-12-31
Budget Start
1994-01-01
Budget End
1994-12-31
Support Year
1
Fiscal Year
1994
Total Cost
Indirect Cost
Name
University of Pennsylvania
Department
Pharmacology
Type
Schools of Medicine
DUNS #
042250712
City
Philadelphia
State
PA
Country
United States
Zip Code
19104
Orlando, Kelly A; Stone, Nicole L; Pittman, Randall N (2006) Rho kinase regulates fragmentation and phagocytosis of apoptotic cells. Exp Cell Res 312:5-15
Orlando, Kelly A; Pittman, Randall N (2006) Rho kinase regulates phagocytosis, surface expression of GlcNAc, and Golgi fragmentation of apoptotic PC12 cells. Exp Cell Res 312:3298-311
Raghupathi, Ramesh; Muir, Judith K; Fulp, Carl T et al. (2003) Acute activation of mitogen-activated protein kinases following traumatic brain injury in the rat: implications for posttraumatic cell death. Exp Neurol 183:438-48
Tang, Y; Zhou, H; Chen, A et al. (2000) The Akt proto-oncogene links Ras to Pak and cell survival signals. J Biol Chem 275:9106-9
Zhou, H; Li, X M; Meinkoth, J et al. (2000) Akt regulates cell survival and apoptosis at a postmitochondrial level. J Cell Biol 151:483-94
Erhardt, J A; Hynicka, W; DiBenedetto, A et al. (1998) A novel F box protein, NFB42, is highly enriched in neurons and induces growth arrest. J Biol Chem 273:35222-7
Mills, J C; Stone, N L; Erhardt, J et al. (1998) Apoptotic membrane blebbing is regulated by myosin light chain phosphorylation. J Cell Biol 140:627-36
Mills, J C; Lee, V M; Pittman, R N (1998) Activation of a PP2A-like phosphatase and dephosphorylation of tau protein characterize onset of the execution phase of apoptosis. J Cell Sci 111 ( Pt 5):625-36
Erhardt, J A; Pittman, R N (1998) Ectopic p21(WAF1) expression induces differentiation-specific cell cycle changes in PC12 cells characteristic of nerve growth factor treatment. J Biol Chem 273:23517-23
Zhou, H; Summers, S A; Birnbaum, M J et al. (1998) Inhibition of Akt kinase by cell-permeable ceramide and its implications for ceramide-induced apoptosis. J Biol Chem 273:16568-75

Showing the most recent 10 out of 13 publications