Necrotic cell death underlies the pathology of many neurodegenerative diseases and is an incapacitating outcome of stroke, ischemia and physical injury. Relatively little is known about genetic control of necrosis, although such mechanistic understanding is clearly critical for effective intervention. We are pursuing a genetic dissection of necrosis mechanisms in the facile model system C. elegans. We have found that hyper-activated ion channels that conduct excess Na +or Ca +2 into neurons initiate a necrotic-like cell death in nematodes (similar events initiate human necrosis). Our analysis of necrosis suppressor loci has identified the ER Ca +2storing protein calreticulin as essential for progression through necrosis. Likewise, the activity of ER Ca +2 release channels potentiates necrosis. We suggest that a rise in intracellular calcium, dependent upon ER Ca +2 stores, is critical for neurotoxicity. We have also identified specific Ca+2-activated calpain proteases and cathepsin proteases as key contributors to necrosis. These may act in a proteolytic pathway to execute cell death. Importantly, intracellular Ca +2 rise and activation of calpain proteases are features of human necrosis, suggesting necrotic death mechanisms are conserved from nematodes to humans. Our Iong term goals are to identify genes that facilitate progression through necrosis and to expand/test a working model in which excess Na + influx signals ER Ca+2 release, with the consequent intracellular Ca +2 rise activating a proteolytic cascade involving specific calpains and cathepsin proteases. We will: 1) use RNAi technology to identify all C. elegans genes needed for efficient progression through necrosis; 2) couple in vivo reporting of intracellular Ca +2 with genetic manipulations to better characterize changes in intracellular Ca+2 that accompany necrosis and to define the critical molecular origins of these changes; 3) use genetic and cell biological approaches to describe mechanistic details of the proteolytic component of necrosis. Overall we expect to exploit unique features of C. elegans to provide a detailed mechanistic description of necrosis, including identification of novel genetic factors influencing this process that may suggest new strategies for limiting devastating effects of necrosis in human injury and disease.

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Research Project (R01)
Project #
2R01NS034435-09
Application #
6736752
Study Section
Special Emphasis Panel (ZRG1-MDCN-3 (02))
Program Officer
Leblanc, Gabrielle G
Project Start
1995-08-01
Project End
2008-12-31
Budget Start
2004-01-01
Budget End
2004-12-31
Support Year
9
Fiscal Year
2004
Total Cost
$361,050
Indirect Cost
Name
Rutgers University
Department
Biochemistry
Type
Schools of Arts and Sciences
DUNS #
001912864
City
New Brunswick
State
NJ
Country
United States
Zip Code
08901
Kamat, Shaunak; Yeola, Shrutika; Zhang, Wenying et al. (2014) NRA-2, a nicalin homolog, regulates neuronal death by controlling surface localization of toxic Caenorhabditis elegans DEG/ENaC channels. J Biol Chem 289:11916-26
Toth, Marton Lorant; Melentijevic, Ilija; Shah, Leena et al. (2012) Neurite sprouting and synapse deterioration in the aging Caenorhabditis elegans nervous system. J Neurosci 32:8778-90
Chatzigeorgiou, Marios; Yoo, Sungjae; Watson, Joseph D et al. (2010) Specific roles for DEG/ENaC and TRP channels in touch and thermosensation in C. elegans nociceptors. Nat Neurosci 13:861-8
Mojsilovic-Petrovic, Jelena; Nedelsky, Natalia; Boccitto, Marco et al. (2009) FOXO3a is broadly neuroprotective in vitro and in vivo against insults implicated in motor neuron diseases. J Neurosci 29:8236-47
Blum, E S; Driscoll, M; Shaham, S (2008) Noncanonical cell death programs in the nematode Caenorhabditis elegans. Cell Death Differ 15:1124-31
Zhang, W; Bianchi, L; Lee, W-H et al. (2008) Intersubunit interactions between mutant DEG/ENaCs induce synthetic neurotoxicity. Cell Death Differ 15:1794-803
Wang, Ying; Apicella Jr, Alfonso; Lee, Sun-Kyung et al. (2008) A glial DEG/ENaC channel functions with neuronal channel DEG-1 to mediate specific sensory functions in C. elegans. EMBO J 27:2388-99
Mano, Itzhak; Straud, Sarah; Driscoll, Monica (2007) Caenorhabditis elegans glutamate transporters influence synaptic function and behavior at sites distant from the synapse. J Biol Chem 282:34412-9
Royal, Dewey C; Bianchi, Laura; Royal, Mary Anne et al. (2005) Temperature-sensitive mutant of the Caenorhabditis elegans neurotoxic MEC-4(d) DEG/ENaC channel identifies a site required for trafficking or surface maintenance. J Biol Chem 280:41976-86
Bianchi, Laura; Gerstbrein, Beate; Frokjaer-Jensen, Christian et al. (2004) The neurotoxic MEC-4(d) DEG/ENaC sodium channel conducts calcium: implications for necrosis initiation. Nat Neurosci 7:1337-44

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