HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 289/1/R68    most recent 00844.2004v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (13) Citing Articles via Google Scholar Google Scholar Articles by Menze, M. A. Articles by Hand, S. C. Search for Related Content PubMed PubMed Citation Articles by Menze, M. A. Articles by Hand, S. C.

COMPARATIVE AND EVOLUTIONARY PHYSIOLOGY

Mitochondrial permeability transition in the crustacean Artemia franciscana: absence of a calcium-regulated pore in the face of profound calcium storage

Division of Cellular, Developmental and Integrative Biology, Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana

Submitted 16 December 2004 ; accepted in final form 14 February 2005

When mammalian mitochondria are exposed to high calcium and phosphate, a massive swelling, uncoupling of respiration, and release of cytochrome c occur. These changes are mediated by opening of the mitochondrial permeability transition pore (MPTP). Activation of the MPTP in vivo in response to hypoxic and oxidative stress leads to necrotic and apoptotic cell death. Considering that embryos of the brine shrimp Artemia franciscana tolerate anoxia for years, we investigated the MPTP in this crustacean to reveal whether pore opening occurs. Minimum molecular constituents of the regulated MPTP in mammals are believed to be the voltage-dependent anion channel, the adenine nucleotide translocators, and cyclophilin D. Western blot analysis revealed that mitochondria from A. franciscana possess all three required components. When measured with a calcium-sensitive fluorescent probe, rat liver mitochondria are shown to release matrix calcium after addition of 100 µM extramitochondrial calcium (MPTP opening), whereas brine shrimp mitochondria continue to take up extramitochondrial calcium and do not release internal stores even up to 1.0 mM exogenously added calcium (no MPTP opening). Furthermore, no swelling of A. franciscana mitochondria in response to added calcium was observed, and no release of cytochrome c could be detected. HgCl₂-dependent swelling and cytochrome c release were readily confirmed, which is consistent with the presence of an "unregulated pore." Although the absence of a regulated MPTP in A. franciscana mitochondria could contribute to the extreme hypoxia tolerance in this species, we speculate that absence of the regulated MPTP may be a general feature of invertebrates.

mitochondria; mitochondrial permeability transition pore; anoxia; apoptosis

This article has been cited by other articles:

				M. E. Jung, A. M. Wilson, X. Ju, Y. Wen, D. B. Metzger, and J. W. Simpkins Ethanol Withdrawal Provokes Opening of the Mitochondrial Membrane Permeability Transition Pore in an Estrogen-Preventable Manner J. Pharmacol. Exp. Ther., March 1, 2009; 328(3): 692 - 698. [Abstract] [Full Text] [PDF]

				M. E. Jung, J. W. Simpkins, A. M. Wilson, H. F. Downey, and R. T. Mallet Intermittent hypoxia conditioning prevents behavioral deficit and brain oxidative stress in ethanol-withdrawn rats J Appl Physiol, August 1, 2008; 105(2): 510 - 517. [Abstract] [Full Text] [PDF]

				M. A. Menze and S. C. Hand Caspase activity during cell stasis: avoidance of apoptosis in an invertebrate extremophile, Artemia franciscana Am J Physiol Regulatory Integrative Comp Physiol, May 1, 2007; 292(5): R2039 - R2047. [Abstract] [Full Text] [PDF]