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Full-Text Articles in Medicine and Health Sciences
Complete Chemical Structures Of Human Mitochondrial Trnas, Takeo Suzuki, Yuka Yashiro, Ittoku Kikuchi, Yuma Ishigami, Hironori Saito, Ikuya Matsuzawa, Shunpei Okada, Mari Mito, Shintaro Iwasaki, Ding Ma, Xuewei Zhao, Kana Asano, Huan Lin, Yohei Kirino, Yuriko Sakaguchi, Tsutomu Suzuki
Complete Chemical Structures Of Human Mitochondrial Trnas, Takeo Suzuki, Yuka Yashiro, Ittoku Kikuchi, Yuma Ishigami, Hironori Saito, Ikuya Matsuzawa, Shunpei Okada, Mari Mito, Shintaro Iwasaki, Ding Ma, Xuewei Zhao, Kana Asano, Huan Lin, Yohei Kirino, Yuriko Sakaguchi, Tsutomu Suzuki
Computational Medicine Center Faculty Papers
Mitochondria generate most cellular energy via oxidative phosphorylation. Twenty-two species of mitochondrial (mt-)tRNAs encoded in mtDNA translate essential subunits of the respiratory chain complexes. mt-tRNAs contain post-transcriptional modifications introduced by nuclear-encoded tRNA-modifying enzymes. They are required for deciphering genetic code accurately, as well as stabilizing tRNA. Loss of tRNA modifications frequently results in severe pathological consequences. Here, we perform a comprehensive analysis of post-transcriptional modifications of all human mt-tRNAs, including 14 previously-uncharacterized species. In total, we find 18 kinds of RNA modifications at 137 positions (8.7% in 1575 nucleobases) in 22 species of human mt-tRNAs. An up-to-date list of 34 …
Gasdermins In Apoptosis: New Players In An Old Game., Corey Rogers, Emad S. Alnemri
Gasdermins In Apoptosis: New Players In An Old Game., Corey Rogers, Emad S. Alnemri
Department of Biochemistry and Molecular Biology Faculty Papers
Apoptosis is a form of programmed cell death (PCD) that plays critical physiological roles in removing superfluous or dangerous cell populations that are unneeded or threatening to the health of the host organism. Although the molecular pathways leading to activation of the apoptotic program have been extensively studied and characterized starting in the 1970s, new evidence suggests that members of the gasdermin superfamily are novel pore-forming proteins that augment apoptosis by permeabilizing the mitochondria and participate in the final stages of the apoptotic program by inducing secondary necrosis/pyroptosis. These findings may explain outstanding questions in the field such as why …
Myc-Mediated Transcriptional Regulation Of The Mitochondrial Chaperone Trap1 Controls Primary And Metastatic Tumor Growth., Ekta Agarwal, Brian J. Altman, Jae Ho Seo, Jagadish C. Ghosh, Andrew V Kossenkov, Hsin-Yao Tang, Shiv Ram Krishn, Lucia R. Languino, Dmitry I. Gabrilovich, David W. Speicher, Chi V. Dang, Dario C. Altieri
Myc-Mediated Transcriptional Regulation Of The Mitochondrial Chaperone Trap1 Controls Primary And Metastatic Tumor Growth., Ekta Agarwal, Brian J. Altman, Jae Ho Seo, Jagadish C. Ghosh, Andrew V Kossenkov, Hsin-Yao Tang, Shiv Ram Krishn, Lucia R. Languino, Dmitry I. Gabrilovich, David W. Speicher, Chi V. Dang, Dario C. Altieri
Department of Cancer Biology Faculty Papers
The role of mitochondria in cancer continues to be debated, and whether exploitation of mitochondrial functions is a general hallmark of malignancy or a tumor- or context-specific response is still unknown. Using a variety of cancer cell lines and several technical approaches, including siRNA-mediated gene silencing, ChIP assays, global metabolomics and focused metabolite analyses, bioenergetics, and cell viability assays, we show that two oncogenic Myc proteins, c-Myc and N-Myc, transcriptionally control the expression of the mitochondrial chaperone TNFR-associated protein- 1 (TRAP1) in cancer. In turn, this Myc-mediated regulation preserved the folding and function of mitochondrial oxidative phosphorylation (OXPHOS) complex II …
Gasdermin Pores Permeabilize Mitochondria To Augment Caspase-3 Activation During Apoptosis And Inflammasome Activation., Corey Rogers, Dan A. Erkes, Alexandria Nardone, Andrew E. Aplin, Teresa Fernandes-Alnemri, Emad S. Alnemri
Gasdermin Pores Permeabilize Mitochondria To Augment Caspase-3 Activation During Apoptosis And Inflammasome Activation., Corey Rogers, Dan A. Erkes, Alexandria Nardone, Andrew E. Aplin, Teresa Fernandes-Alnemri, Emad S. Alnemri
Department of Biochemistry and Molecular Biology Faculty Papers
Gasdermin E (GSDME/DFNA5) cleavage by caspase-3 liberates the GSDME-N domain, which mediates pyroptosis by forming pores in the plasma membrane. Here we show that GSDME-N also permeabilizes the mitochondrial membrane, releasing cytochrome c and activating the apoptosome. Cytochrome c release and caspase-3 activation in response to intrinsic and extrinsic apoptotic stimuli are significantly reduced in GSDME-deficient cells comparing with wild type cells. GSDME deficiency also accelerates cell growth in culture and in a mouse model of melanoma. Phosphomimetic mutation of the highly conserved phosphorylatable Thr6 residue of GSDME, inhibits its pore-forming activity, thus uncovering a potential mechanism by which GSDME …
Highly Efficient 5' Capping Of Mitochondrial Rna With Nad+ And Nadh By Yeast And Human Mitochondrial Rna Polymerase, Jeremy G Bird, Urmimala Basu, David Kuster, Aparna Ramachandran, Ewa Grudzien-Nogalska, Atif Towheed, Douglas C. Wallace, Megerditch Kiledjian, Dmitry Temiakov, Smita S. Patel, Richard H. Ebright, Bryce E. Nickels
Highly Efficient 5' Capping Of Mitochondrial Rna With Nad+ And Nadh By Yeast And Human Mitochondrial Rna Polymerase, Jeremy G Bird, Urmimala Basu, David Kuster, Aparna Ramachandran, Ewa Grudzien-Nogalska, Atif Towheed, Douglas C. Wallace, Megerditch Kiledjian, Dmitry Temiakov, Smita S. Patel, Richard H. Ebright, Bryce E. Nickels
Department of Biochemistry and Molecular Biology Faculty Papers
Bacterial and eukaryotic nuclear RNA polymerases (RNAPs) cap RNA with the oxidized and reduced forms of the metabolic effector nicotinamide adenine dinucleotide, NAD+ and NADH, using NAD+ and NADH as non-canonical initiating nucleotides for transcription initiation. Here, we show that mitochondrial RNAPs (mtRNAPs) cap RNA with NAD+ and NADH, and do so more efficiently than nuclear RNAPs. Direct quantitation of NAD+- and NADH-capped RNA demonstrates remarkably high levels of capping in vivo: up to ~60% NAD+ and NADH capping of yeast mitochondrial transcripts, and up to ~15% NAD+ capping of human mitochondrial transcripts. The capping efficiency is determined by promoter …
Natural And Induced Mitochondrial Phosphate Carrier Loss: Differential Dependence Of Mitochondrial Metabolism And Dynamics And Cell Survival On The Extent Of Depletion., Erin L. Seifert, Aniko Gál, Michelle G. Acoba, Qipei Li, Lauren Anderson-Pullinger, Tünde Golenár, Cynthia Moffat, Neal Sondheimer, Steven M. Claypool, György Hajnóczky
Natural And Induced Mitochondrial Phosphate Carrier Loss: Differential Dependence Of Mitochondrial Metabolism And Dynamics And Cell Survival On The Extent Of Depletion., Erin L. Seifert, Aniko Gál, Michelle G. Acoba, Qipei Li, Lauren Anderson-Pullinger, Tünde Golenár, Cynthia Moffat, Neal Sondheimer, Steven M. Claypool, György Hajnóczky
Department of Pathology, Anatomy, and Cell Biology Faculty Papers
The relevance of mitochondrial phosphate carrier (PiC), encoded by SLC25A3, in bioenergetics is well accepted. However, little is known about the mechanisms mediating the cellular impairments induced by pathological SLC25A3 variants. To this end, we investigated the pathogenicity of a novel compound heterozygous mutation in SLC25A3 First, each variant was modeled in yeast, revealing that substituting GSSAS for QIP within the fifth matrix loop is incompatible with survival on non-fermentable substrate, whereas the L200W variant is functionally neutral. Next, using skin fibroblasts from an individual expressing these variants and HeLa cells with varying degrees of PiC depletion, PiC loss of …
Molecular Basis And Consequences Of The Cytochrome C-Trna Interaction., Cuiping Liu, Aaron J Stonestrom, Thomas Christian, Jeongsik Yong, Ryuichi Takase, Ya-Ming Hou, Xiaolu Yang
Molecular Basis And Consequences Of The Cytochrome C-Trna Interaction., Cuiping Liu, Aaron J Stonestrom, Thomas Christian, Jeongsik Yong, Ryuichi Takase, Ya-Ming Hou, Xiaolu Yang
Department of Biochemistry and Molecular Biology Faculty Papers
The intrinsic apoptosis pathway occurs through the release of mitochondrial cytochrome c to the cytosol, where it promotes activation of the caspase family of proteases. The observation that tRNA binds to cytochrome c revealed a previously unexpected mode of apoptotic regulation. However, the molecular characteristics of this interaction, and its impact on each interaction partner, are not well understood. Using a novel fluorescence assay, we show here that cytochrome c binds to tRNA with an affinity comparable with other tRNA-protein binding interactions and with a molecular ratio of ∼3:1. Cytochrome c recognizes the tertiary structural features of tRNA, particularly in …
Isoform- And Species-Specific Control Of Inositol 1,4,5-Trisphosphate (Ip3) Receptors By Reactive Oxygen Species., Száva Bánsághi, Tünde Golenár, Muniswamy Madesh, György Csordás, Satish P. Ramachandrarao, Kumar Sharma, David I Yule, Suresh K Joseph, György Hajnóczky
Isoform- And Species-Specific Control Of Inositol 1,4,5-Trisphosphate (Ip3) Receptors By Reactive Oxygen Species., Száva Bánsághi, Tünde Golenár, Muniswamy Madesh, György Csordás, Satish P. Ramachandrarao, Kumar Sharma, David I Yule, Suresh K Joseph, György Hajnóczky
Department of Pathology, Anatomy, and Cell Biology Faculty Papers
Reactive oxygen species (ROS) stimulate cytoplasmic [Ca(2+)] ([Ca(2+)]c) signaling, but the exact role of the IP3 receptors (IP3R) in this process remains unclear. IP3Rs serve as a potential target of ROS produced by both ER and mitochondrial enzymes, which might locally expose IP3Rs at the ER-mitochondrial associations. Also, IP3Rs contain multiple reactive thiols, common molecular targets of ROS. Therefore, we have examined the effect of superoxide anion (O2) on IP3R-mediated Ca(2+) signaling. In human HepG2, rat RBL-2H3, and chicken DT40 cells, we observed [Ca(2+)]c spikes and frequency-modulated oscillations evoked by a O2 donor, xanthine (X) + xanthine oxidase (XO), dose-dependently. …
Mitochondrial Genome Sequence Analysis: A Custom Bioinformatics Pipeline Substantially Improves Affymetrix Mitochip V2.0 Call Rate And Accuracy., Hongbo M Xie, Juan C Perin, Theodore G Schurr, Matthew C Dulik, Sergey I Zhadanov, Joseph A Baur, Michael P King, Emily Place, Colleen Clarke, Michael Grauer, Jonathan Schug, Avni Santani, Anthony Albano, Cecilia Kim, Vincent Procaccio, Hakon Hakonarson, Xiaowu Gai, Marni J Falk
Mitochondrial Genome Sequence Analysis: A Custom Bioinformatics Pipeline Substantially Improves Affymetrix Mitochip V2.0 Call Rate And Accuracy., Hongbo M Xie, Juan C Perin, Theodore G Schurr, Matthew C Dulik, Sergey I Zhadanov, Joseph A Baur, Michael P King, Emily Place, Colleen Clarke, Michael Grauer, Jonathan Schug, Avni Santani, Anthony Albano, Cecilia Kim, Vincent Procaccio, Hakon Hakonarson, Xiaowu Gai, Marni J Falk
Department of Biochemistry and Molecular Biology Faculty Papers
BACKGROUND: Mitochondrial genome sequence analysis is critical to the diagnostic evaluation of mitochondrial disease. Existing methodologies differ widely in throughput, complexity, cost efficiency, and sensitivity of heteroplasmy detection. Affymetrix MitoChip v2.0, which uses a sequencing-by-genotyping technology, allows potentially accurate and high-throughput sequencing of the entire human mitochondrial genome to be completed in a cost-effective fashion. However, the relatively low call rate achieved using existing software tools has limited the wide adoption of this platform for either clinical or research applications. Here, we report the design and development of a custom bioinformatics software pipeline that achieves a much improved call rate …
Mitochondrial Mislocalization Underlies Abeta42-Induced Neuronal Dysfunction In A Drosophila Model Of Alzheimer's Disease., Kanae Iijima-Ando, Stephen A Hearn, Christopher Shenton, Anthony Gatt, Lijuan Zhao, Koichi Iijima
Mitochondrial Mislocalization Underlies Abeta42-Induced Neuronal Dysfunction In A Drosophila Model Of Alzheimer's Disease., Kanae Iijima-Ando, Stephen A Hearn, Christopher Shenton, Anthony Gatt, Lijuan Zhao, Koichi Iijima
Department of Biochemistry and Molecular Biology Faculty Papers
The amyloid-beta 42 (Abeta42) is thought to play a central role in the pathogenesis of Alzheimer's disease (AD). However, the molecular mechanisms by which Abeta42 induces neuronal dysfunction and degeneration remain elusive. Mitochondrial dysfunctions are implicated in AD brains. Whether mitochondrial dysfunctions are merely a consequence of AD pathology, or are early seminal events in AD pathogenesis remains to be determined. Here, we show that Abeta42 induces mitochondrial mislocalization, which contributes to Abeta42-induced neuronal dysfunction in a transgenic Drosophila model. In the Abeta42 fly brain, mitochondria were reduced in axons and dendrites, and accumulated in the somata without severe mitochondrial …
Mitochondrial Mislocalization Underlies Abeta42-Induced Neuronal Dysfunction In A Drosophila Model Of Alzheimer's Disease., Kanae Iijima-Ando, Stephen A Hearn, Christopher Shenton, Anthony Gatt, Lijuan Zhao, Koichi Iijima
Mitochondrial Mislocalization Underlies Abeta42-Induced Neuronal Dysfunction In A Drosophila Model Of Alzheimer's Disease., Kanae Iijima-Ando, Stephen A Hearn, Christopher Shenton, Anthony Gatt, Lijuan Zhao, Koichi Iijima
Department of Biochemistry and Molecular Biology Faculty Papers
The amyloid-beta 42 (Abeta42) is thought to play a central role in the pathogenesis of Alzheimer's disease (AD). However, the molecular mechanisms by which Abeta42 induces neuronal dysfunction and degeneration remain elusive. Mitochondrial dysfunctions are implicated in AD brains. Whether mitochondrial dysfunctions are merely a consequence of AD pathology, or are early seminal events in AD pathogenesis remains to be determined. Here, we show that Abeta42 induces mitochondrial mislocalization, which contributes to Abeta42-induced neuronal dysfunction in a transgenic Drosophila model. In the Abeta42 fly brain, mitochondria were reduced in axons and dendrites, and accumulated in the somata without severe mitochondrial …