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) Supplemental Figures All Versions of this Article: 291/1/C176    most recent 00348.2005v1 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 (17) Citing Articles via Google Scholar Google Scholar Articles by Twig, G. Articles by Shirihai, O. S. Search for Related Content PubMed PubMed Citation Articles by Twig, G. Articles by Shirihai, O. S.

PROTEIN AND VESICLE TRAFFICKING, CYTOSKELETON

Tagging and tracking individual networks within a complex mitochondrial web with photoactivatable GFP

¹Department of Pharmacology and Experimental Therapeutics, Tufts University School of Medicine, Boston, Massachusetts; and ²Jerome Schottenstein Center, Department of Physics, Bar-Ilan University, Ramat-Gan, Israel

Submitted 15 July 2005 ; accepted in final form 2 February 2006

Assembly of mitochondria into networks supports fuel metabolism and calcium transport and is involved in the cellular response to apoptotic stimuli. A mitochondrial network is defined as a continuous matrix lumen whose boundaries limit molecular diffusion. Observation of individual networks has proven challenging in live cells that possess dense populations of mitochondria. Investigation into the electrical and morphological properties of mitochondrial networks has therefore not yielded consistent conclusions. In this study we used matrix-targeted, photoactivatable green fluorescent protein to tag single mitochondrial networks. This approach, coupled with real-time monitoring of mitochondrial membrane potential, permitted the examination of matrix lumen continuity and fusion and fission events over time. We found that adjacent and intertwined mitochondrial structures often represent a collection of distinct networks. We additionally found that all areas of a single network are invariably equipotential, suggesting that a heterogeneous pattern of membrane potential within a cell's mitochondria represents differences between discrete networks. Interestingly, fission events frequently occurred without any gross morphological changes and particularly without fragmentation. These events, which are invisible under standard confocal microscopy, redefine the mitochondrial network boundaries and result in electrically disconnected daughter units.

membrane potential; fusion; fission; heterogeneity; green fluorescent protein; tetramethylrhodamine ethyl ester perchlorate

This article has been cited by other articles:

				A. J.A. Molina, J. D. Wikstrom, L. Stiles, G. Las, H. Mohamed, A. Elorza, G. Walzer, G. Twig, S. Katz, B. E. Corkey, et al. Mitochondrial Networking Protects {beta}-Cells From Nutrient-Induced Apoptosis Diabetes, October 1, 2009; 58(10): 2303 - 2315. [Abstract] [Full Text] [PDF]

				M. Liesa, M. Palacin, and A. Zorzano Mitochondrial Dynamics in Mammalian Health and Disease Physiol Rev, July 1, 2009; 89(3): 799 - 845. [Abstract] [Full Text] [PDF]

				S. B. Berman, Y.-b. Chen, B. Qi, J. M. McCaffery, E. B. Rucker III, S. Goebbels, K.-A. Nave, B. A. Arnold, E. A. Jonas, F. J. Pineda, et al. Bcl-xL increases mitochondrial fission, fusion, and biomass in neurons J. Cell Biol., March 9, 2009; 184(5): 707 - 719. [Abstract] [Full Text] [PDF]