Nucleic Acids Research, 2002, Vol. 30, No. 9 1929-1934
© 2002 Oxford University Press
Modulation of mitochondrial transcription in response to mtDNA depletion and repletion in HeLa cells
Department of Biochemistry, Rollins Research Center, Emory University School of Medicine, Atlanta, GA 30322, USA
The steady-state amounts of mitochondrial transcripts and transcription proteins were analyzed during mtDNA depletion and subsequent repletion to gain insight into the regulation of human mitochondrial gene expression. As documented previously, HeLa cells depleted of mtDNA via treatment with ethidium bromide (EB) were found to contain reduced steady-state levels of the mitochondrial transcription factor h-mtTFA. When partially mtDNA-depleted cells were cultured in the absence of EB, h-mtTFA recovered to normal levels at a significantly slower rate than mtDNA. Human mtRNA polymerase exhibited a similar depletionrepletion profile, suggesting that the mitochondrial transcription machinery is coordinately regulated in response to changes in mtDNA copy number. Newly synthesized mitochondrial transcripts were detected early in the recovery phase, despite the fact that mtDNA, h-mtTFA and h-mtRNA polymerase were simultaneously depleted. Although delayed relative to mtDNA, the amounts of h-mtTFA and h-mtRNA polymerase sharply increased during the later stages of the recovery phase, which was accompanied by accelerated rates of transcription and mtDNA replication. Altogether, these data indicate that when mtDNA copy number is low, it is beneficial to prevent accumulation of mitochondrial transcription proteins. In addition, h-mtTFA and h-mtRNA polymerase are either normally present in excess of the amount required for transcription or their activity is up-regulated to ensure continued expression and transcription-dependent replication of the mitochondrial genome during mtDNA-depleted states.
* To whom correspondence should be addressed. Tel: +1 404 727 3798; Fax: +1 404 727 3954; Email: gshadel{at}emory.edu
![]()
CiteULike
Connotea
Del.icio.us What's this?
This article has been cited by other articles:
![]() |
A. P. Rebelo, S. L. Williams, and C. T. Moraes In vivo methylation of mtDNA reveals the dynamics of protein-mtDNA interactions Nucleic Acids Res., November 1, 2009; 37(20): 6701 - 6715. [Abstract] [Full Text] [PDF] |
||||
![]() |
I. D. Rosa, S. Goffart, M. Wurm, C. Wiek, F. Essmann, S. Sobek, P. Schroeder, H. Zhang, J. Krutmann, H. Hanenberg, et al. Adaptation of topoisomerase I paralogs to nuclear and mitochondrial DNA Nucleic Acids Res., October 1, 2009; 37(19): 6414 - 6428. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. R. Bacman, S. L. Williams, and C. T. Moraes Intra- and inter-molecular recombination of mitochondrial DNA after in vivo induction of multiple double-strand breaks Nucleic Acids Res., July 1, 2009; 37(13): 4218 - 4226. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. J. Bowles, J.-H. Lee, R. Alberio, R. E. I. Lloyd, D. Stekel, K. H. S. Campbell, and J. C. St. John Contrasting Effects of in Vitro Fertilization and Nuclear Transfer on the Expression of mtDNA Replication Factors Genetics, July 1, 2007; 176(3): 1511 - 1526. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Cotney, Z. Wang, and G. S. Shadel Relative abundance of the human mitochondrial transcription system and distinct roles for h-mtTFB1 and h-mtTFB2 in mitochondrial biogenesis and gene expression Nucleic Acids Res., June 18, 2007; (2007) gkm424v2. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Amaral, J. Ramalho-Santos, and J. C. St John The expression of polymerase gamma and mitochondrial transcription factor A and the regulation of mitochondrial DNA content in mature human sperm Hum. Reprod., June 1, 2007; 22(6): 1585 - 1596. [Abstract] [Full Text] [PDF] |
||||
![]() |
Z. Wang, J. Cotney, and G. S. Shadel Human Mitochondrial Ribosomal Protein MRPL12 Interacts Directly with Mitochondrial RNA Polymerase to Modulate Mitochondrial Gene Expression J. Biol. Chem., April 27, 2007; 282(17): 12610 - 12618. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. L. O. Pohjoismaki, S. Wanrooij, A. K. Hyvarinen, S. Goffart, I. J. Holt, J. N. Spelbrink, and H. T. Jacobs Alterations to the expression level of mitochondrial transcription factor A, TFAM, modify the mode of mitochondrial DNA replication in cultured human cells Nucleic Acids Res., November 6, 2006; 34(20): 5815 - 5828. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. D. Taylor, H. Zhang, J. S. Eaton, M. S. Rodeheffer, M. A. Lebedeva, T. W. O'Rourke, W. Siede, and G. S. Shadel The Conserved Mec1/Rad53 Nuclear Checkpoint Pathway Regulates Mitochondrial DNA Copy Number in Saccharomyces cerevisiae Mol. Biol. Cell, June 1, 2005; 16(6): 3010 - 3018. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Y. Park, G. H. Choi, H. I. Choi, J. Ryu, C. Y. Jung, and W. Lee Depletion of Mitochondrial DNA Causes Impaired Glucose Utilization and Insulin Resistance in L6 GLUT4myc Myocytes J. Biol. Chem., March 18, 2005; 280(11): 9855 - 9864. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. Maniura-Weber, S. Goffart, H. L. Garstka, J. Montoya, and R. J. Wiesner Transient overexpression of mitochondrial transcription factor A (TFAM) is sufficient to stimulate mitochondrial DNA transcription, but not sufficient to increase mtDNA copy number in cultured cells Nucleic Acids Res., November 16, 2004; 32(20): 6015 - 6027. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. Kanki, K. Ohgaki, M. Gaspari, C. M. Gustafsson, A. Fukuoh, N. Sasaki, N. Hamasaki, and D. Kang Architectural Role of Mitochondrial Transcription Factor A in Maintenance of Human Mitochondrial DNA Mol. Cell. Biol., November 15, 2004; 24(22): 9823 - 9834. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. Hashiguchi, J. A. Stuart, N. C. de Souza-Pinto, and V. A. Bohr The C-terminal {alpha}O helix of human Ogg1 is essential for 8-oxoguanine DNA glycosylase activity: the mitochondrial {beta}-Ogg1 lacks this domain and does not have glycosylase activity Nucleic Acids Res., October 19, 2004; 32(18): 5596 - 5608. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Wellmann, C. Buhrer, E. Moderegger, A. Zelmer, R. Kirschner, P. Koehne, J. Fujita, and K. Seeger Oxygen-regulated expression of the RNA-binding proteins RBM3 and CIRP by a HIF-1-independent mechanism J. Cell Sci., May 1, 2004; 117(9): 1785 - 1794. [Abstract] [Full Text] [PDF] |
||||
![]() |
J.A. Stuart, K. Hashiguchi, D.M. Wilson III, W.C. Copeland, N.C. Souza-Pinto, and V.A. Bohr DNA base excision repair activities and pathway function in mitochondrial and cellular lysates from cells lacking mitochondrial DNA Nucleic Acids Res., April 23, 2004; 32(7): 2181 - 2192. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. L. Garstka, W. E. Schmitt, J. Schultz, B. Sogl, B. Silakowski, A. Perez-Martos, J. Montoya, and R. J. Wiesner Import of mitochondrial transcription factor A (TFAM) into rat liver mitochondria stimulates transcription of mitochondrial DNA Nucleic Acids Res., September 1, 2003; 31(17): 5039 - 5047. [Abstract] [Full Text] [PDF] |
||||
![]() |
V. McCulloch and G. S. Shadel Human Mitochondrial Transcription Factor B1 Interacts with the C-Terminal Activation Region of h-mtTFA and Stimulates Transcription Independently of Its RNA Methyltransferase Activity Mol. Cell. Biol., August 15, 2003; 23(16): 5816 - 5824. [Abstract] [Full Text] [PDF] |
||||
![]() |
F. Diaz, M. P. Bayona-Bafaluy, M. Rana, M. Mora, H. Hao, and C. T. Moraes Human mitochondrial DNA with large deletions repopulates organelles faster than full-length genomes under relaxed copy number control Nucleic Acids Res., November 1, 2002; 30(21): 4626 - 4633. [Abstract] [Full Text] [PDF] |
||||






