(Supported by NSF MCB 9513439 to K. Kinnally). Apoptosis is integral to a wide range of biological processes. Recent findings from many laboratories suggest that mitochondria play a pivotal role in the apoptotic cascade in several cell types. For instance, apoptosis can be triggered in cells and cell-free systems by drugs that release proteins from mitochondria. This process can be blocked by bcl-2 and related apoptosis inhibitors that have been localized to mitochondria. Furthermore, in many cell types, the apoptosis-induced loss of mitochondrial membrane potential precedes hallmark events like loss of plasma membrane lipid asymmetry and nuclear changes such as chromatin condensation and DNA fragmentation. These observations suggest that changes in mitochondrial membrane permeability and organization may be integral, early steps in the apoptotic cascade. Experiments were initiated that will allow us to evaluate the effects of mechanically releasing discrete amounts of mitochondrial contents into living cells in the absence of agents (i.e., drugs) that may have pleiotropic effects. Preliminary work at the BMIRR reveals that just a single 5-7 ns pulse of 532 nm light from the laser microsurgery system is all that is needed to lyse a mitochondria within a living cell, and that 10-20 mitochondria can be lysed within a 1 min period. Preliminary data, which has formed the basis of a pending NIH grant, reveals that lysing just 10 of the 100-200 mitochondria within a cultured cell with this method appears to induce the cell to exit the cell cycle. Furthermore, since all the mitochondria in the irradiated cells eventually depolarized, there must also be an amplification of the laser-induced signal. Experiments are underway to determine whether the cells that exit the cell cycle ultimately die by the apoptotic or necrotic pathways. A timetable of onset of various markers is being established. Efforts are being made to visualize the wave of mitochondrial depolarization.

Agency
National Institute of Health (NIH)
Institute
National Center for Research Resources (NCRR)
Type
Biotechnology Resource Grants (P41)
Project #
5P41RR001219-18
Application #
6119664
Study Section
Project Start
1999-01-01
Project End
1999-12-31
Budget Start
1998-10-01
Budget End
1999-09-30
Support Year
18
Fiscal Year
1999
Total Cost
Indirect Cost
Name
Wadsworth Center
Department
Type
DUNS #
110521739
City
Menands
State
NY
Country
United States
Zip Code
12204
Booth, David M; Enyedi, Balázs; Geiszt, Miklós et al. (2016) Redox Nanodomains Are Induced by and Control Calcium Signaling at the ER-Mitochondrial Interface. Mol Cell 63:240-248
Takvorian, Peter M; Buttle, Karolyn F; Mankus, David et al. (2013) The multilayered interlaced network (MIN) in the sporoplasm of the microsporidium Anncaliia algerae is derived from Golgi. J Eukaryot Microbiol 60:166-78
Mannella, Carmen A; Lederer, W Jonathan; Jafri, M Saleet (2013) The connection between inner membrane topology and mitochondrial function. J Mol Cell Cardiol 62:51-7
Forbes, Stephen J; Martinelli, Daniel; Hsieh, Chyongere et al. (2012) Association of a protective monoclonal IgA with the O antigen of Salmonella enterica serovar Typhimurium impacts type 3 secretion and outer membrane integrity. Infect Immun 80:2454-63
Wang, Ruiwu; Zhong, Xiaowei; Meng, Xing et al. (2011) Localization of the dantrolene-binding sequence near the FK506-binding protein-binding site in the three-dimensional structure of the ryanodine receptor. J Biol Chem 286:12202-12
Marko, Michael; Leith, Ardean; Hsieh, Chyongere et al. (2011) Retrofit implementation of Zernike phase plate imaging for cryo-TEM. J Struct Biol 174:400-12
Springer, Deborah J; Ren, Ping; Raina, Ramesh et al. (2010) Extracellular fibrils of pathogenic yeast Cryptococcus gattii are important for ecological niche, murine virulence and human neutrophil interactions. PLoS One 5:e10978
Li, Chunhao; Sal, Melanie; Marko, Michael et al. (2010) Differential regulation of the multiple flagellins in spirochetes. J Bacteriol 192:2596-603
McEwen, Bruce F; Dong, Yimin (2010) Contrasting models for kinetochore microtubule attachment in mammalian cells. Cell Mol Life Sci 67:2163-72
Palladino, Michael J (2010) Modeling mitochondrial encephalomyopathy in Drosophila. Neurobiol Dis 40:40-5

Showing the most recent 10 out of 252 publications