1
|
Ma Y, Zhu S, Lv T, Gu X, Feng H, Zhen J, Xin W, Wan Q. SQSTM1/p62 Controls mtDNA Expression and Participates in Mitochondrial Energetic Adaption via MRPL12. iScience 2020; 23:101428. [PMID: 32805647 PMCID: PMC7452302 DOI: 10.1016/j.isci.2020.101428] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 06/19/2020] [Accepted: 07/30/2020] [Indexed: 02/07/2023] Open
Abstract
Mitochondrial DNA (mtDNA) encodes thirteen core components of OXPHOS complexes, and its steady expression is crucial for cellular energy homeostasis. However, the regulation of mtDNA expression machinery, along with its sensing mechanism to energetic stresses, is not fully understood. Here, we identified SQSTM1/p62 as an important regulator of mtDNA expression machinery, which could effectively induce mtDNA expression and the effects were mediated by p38-dependent upregulation of mitochondrial ribosomal protein L12 (MRPL12) in renal tubular epithelial cells (TECs), a highly energy-demanding cell type related to OXPHOS. We further identified a direct binding site within the MRPL12 promoter to ATF2, the downstream effector of p38. Besides, SQSTM1/p62-induced mtDNA expression is involved in both serum deprivation and hypoxia-induced mitochondrial response, which was further highlighted by kidney injury phenotype of TECs-specific SQSTM1/p62 knockout mice. Collectively, these data suggest that SQSTM1/p62 is a key regulator and energetic sensor of mtDNA expression machinery. SQSTM1/p62 is an important regulator of mtDNA expression machinery SQSTM1/p62 induces MRPL12 expression via activating p38/ATF2 signaling pathway SQSTM1/p62 maintains TECs mitochondrial homeostasis and kidney function
Collapse
Affiliation(s)
- Yuan Ma
- Renal Division, Peking University First Hospital, Peking University Institute of Nephrology, Beijing 100034, China
| | - Suwei Zhu
- School of Medicine, Cheeloo College of Medicine, Shandong University, Jinan 250012, China
| | - Tingting Lv
- School of Medicine, Cheeloo College of Medicine, Shandong University, Jinan 250012, China
| | - Xia Gu
- School of Medicine, Cheeloo College of Medicine, Shandong University, Jinan 250012, China
| | - Hong Feng
- Cancer Center, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan 250012, China
| | - Junhui Zhen
- Department of Pathology, School of Medicine, Cheeloo College of Medicine, Shandong University, Jinan 250012, China
| | - Wei Xin
- Department of Central Laboratory, Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan 250012, China; Department of Central Laboratory, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan 250012, China.
| | - Qiang Wan
- Department of Endocrinology, Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan 250012, China.
| |
Collapse
|
2
|
Nouws J, Goswami AV, Bestwick M, McCann BJ, Surovtseva YV, Shadel GS. Mitochondrial Ribosomal Protein L12 Is Required for POLRMT Stability and Exists as Two Forms Generated by Alternative Proteolysis during Import. J Biol Chem 2015; 291:989-97. [PMID: 26586915 DOI: 10.1074/jbc.m115.689299] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Indexed: 01/21/2023] Open
Abstract
To translate the 13 mtDNA-encoded mRNAs involved in oxidative phosphorylation (OXPHOS), mammalian mitochondria contain a dedicated set of ribosomes comprising rRNAs encoded by the mitochondrial genome and mitochondrial ribosomal proteins (MRPs) that are encoded by nuclear genes and imported into the matrix. In addition to their role in the ribosome, several MRPs have auxiliary functions or have been implicated in other cellular processes like cell cycle regulation and apoptosis. For example, we have shown that human MRPL12 binds and activates mitochondrial RNA polymerase (POLRMT), and hence has distinct functions in the ribosome and mtDNA transcription. Here we provide concrete evidence that there are two mature forms of mammalian MRPL12 that are generated by a two-step cleavage during import, involving efficient cleavage by mitochondrial processing protease and a second inefficient or regulated cleavage by mitochondrial intermediate protease. We also show that knock-down of MRPL12 by RNAi results in instability of POLRMT, but not other primary mitochondrial transcription components, and a corresponding decrease in mitochondrial transcription rates. Knock-down of MRPL10, the binding partner of MRPL12 in the ribosome, results in selective degradation of the mature long form of MRPL12, but has no effect on POLRMT. We propose that the two forms of MRPL12 are involved in homeostatic regulation of mitochondrial transcription and ribosome biogenesis that likely contribute to cell cycle, growth regulation, and longevity pathways to which MRPL12 has been linked.
Collapse
Affiliation(s)
| | | | - Megan Bestwick
- From the Departments of Pathology and the Department of Chemistry, Linfield College, McMinnville, Oregon 97128, and
| | - Beverly Jo McCann
- From the Departments of Pathology and the Department of Biology, Technische Universität Darmstadt, 64287 Darmstadt, Germany
| | | | - Gerald S Shadel
- From the Departments of Pathology and Genetics, Yale School of Medicine, New Haven, Connecticut 06520-8023,
| |
Collapse
|
3
|
Martin B, Chadwick W, Janssens J, Premont RT, Schmalzigaug R, Becker KG, Lehrmann E, Wood WH, Zhang Y, Siddiqui S, Park SS, Cong WN, Daimon CM, Maudsley S. GIT2 Acts as a Systems-Level Coordinator of Neurometabolic Activity and Pathophysiological Aging. Front Endocrinol (Lausanne) 2015; 6:191. [PMID: 26834700 PMCID: PMC4716144 DOI: 10.3389/fendo.2015.00191] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Accepted: 12/14/2015] [Indexed: 01/08/2023] Open
Abstract
Aging represents one of the most complicated and highly integrated somatic processes. Healthy aging is suggested to rely upon the coherent regulation of hormonal and neuronal communication between the central nervous system and peripheral tissues. The hypothalamus is one of the main structures in the body responsible for sustaining an efficient interaction between energy balance and neurological activity and therefore likely coordinates multiple systems in the aging process. We previously identified, in hypothalamic and peripheral tissues, the G protein-coupled receptor kinase interacting protein 2 (GIT2) as a stress response and aging regulator. As metabolic status profoundly affects aging trajectories, we investigated the role of GIT2 in regulating metabolic activity. We found that genomic deletion of GIT2 alters hypothalamic transcriptomic signatures related to diabetes and metabolic pathways. Deletion of GIT2 reduced whole animal respiratory exchange ratios away from those related to primary glucose usage for energy homeostasis. GIT2 knockout (GIT2KO) mice demonstrated lower insulin secretion levels, disruption of pancreatic islet beta cell mass, elevated plasma glucose, and insulin resistance. High-dimensionality transcriptomic signatures from islets isolated from GIT2KO mice indicated a disruption of beta cell development. Additionally, GIT2 expression was prematurely elevated in pancreatic and hypothalamic tissues from diabetic-state mice (db/db), compared to age-matched wild type (WT) controls, further supporting the role of GIT2 in metabolic regulation and aging. We also found that the physical interaction of pancreatic GIT2 with the insulin receptor and insulin receptor substrate 2 was diminished in db/db mice compared to WT mice. Therefore, GIT2 appears to exert a multidimensional "keystone" role in regulating the aging process by coordinating somatic responses to energy deficits.
Collapse
Affiliation(s)
- Bronwen Martin
- Metabolism Unit, National Institute on Aging, National Institutes of Health, Baltimore, MD, USA
| | - Wayne Chadwick
- Receptor Pharmacology Unit, National Institute on Aging, National Institutes of Health, Baltimore, MD, USA
| | - Jonathan Janssens
- Translational Neurobiology Group, VIB Department of Molecular Genetics, University of Antwerp, Antwerp, Belgium
- Laboratory of Neurogenetics, Institute Born-Bunge, University of Antwerp, Antwerp, Belgium
| | - Richard T. Premont
- Department of Medicine, Gastroenterology Division, Duke University, Durham, NC, USA
| | - Robert Schmalzigaug
- Department of Medicine, Gastroenterology Division, Duke University, Durham, NC, USA
| | - Kevin G. Becker
- Gene Expression and Genomics Unit, National Institutes of Health, Baltimore, MD, USA
| | - Elin Lehrmann
- Gene Expression and Genomics Unit, National Institutes of Health, Baltimore, MD, USA
| | - William H. Wood
- Gene Expression and Genomics Unit, National Institutes of Health, Baltimore, MD, USA
| | - Yongqing Zhang
- Gene Expression and Genomics Unit, National Institutes of Health, Baltimore, MD, USA
| | - Sana Siddiqui
- Receptor Pharmacology Unit, National Institute on Aging, National Institutes of Health, Baltimore, MD, USA
| | - Sung-Soo Park
- Receptor Pharmacology Unit, National Institute on Aging, National Institutes of Health, Baltimore, MD, USA
| | - Wei-na Cong
- Metabolism Unit, National Institute on Aging, National Institutes of Health, Baltimore, MD, USA
| | - Caitlin M. Daimon
- Metabolism Unit, National Institute on Aging, National Institutes of Health, Baltimore, MD, USA
| | - Stuart Maudsley
- Receptor Pharmacology Unit, National Institute on Aging, National Institutes of Health, Baltimore, MD, USA
- Translational Neurobiology Group, VIB Department of Molecular Genetics, University of Antwerp, Antwerp, Belgium
- Laboratory of Neurogenetics, Institute Born-Bunge, University of Antwerp, Antwerp, Belgium
- *Correspondence: Stuart Maudsley,
| |
Collapse
|
5
|
Shutt TE, Shadel GS. A compendium of human mitochondrial gene expression machinery with links to disease. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2010; 51:360-79. [PMID: 20544879 PMCID: PMC2886302 DOI: 10.1002/em.20571] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Mammalian mitochondrial DNA encodes 37 essential genes required for ATP production via oxidative phosphorylation, instability or misregulation of which is associated with human diseases and aging. Other than the mtDNA-encoded RNA species (13 mRNAs, 12S and 16S rRNAs, and 22 tRNAs), the remaining factors needed for mitochondrial gene expression (i.e., transcription, RNA processing/modification, and translation), including a dedicated set of mitochondrial ribosomal proteins, are products of nuclear genes that are imported into the mitochondrial matrix. Herein, we inventory the human mitochondrial gene expression machinery, and, while doing so, we highlight specific associations of these regulatory factors with human disease. Major new breakthroughs have been made recently in this burgeoning area that set the stage for exciting future studies on the key outstanding issue of how mitochondrial gene expression is regulated differentially in vivo. This should promote a greater understanding of why mtDNA mutations and dysfunction cause the complex and tissue-specific pathology characteristic of mitochondrial disease states and how mitochondrial dysfunction contributes to more common human pathology and aging.
Collapse
Affiliation(s)
- Timothy E. Shutt
- Department of Pathology, Yale University School of Medicine, 310 Cedar Street, P.O. Box 208023, New haven, CT 06520-8023
| | - Gerald S. Shadel
- Department of Pathology, Yale University School of Medicine, 310 Cedar Street, P.O. Box 208023, New haven, CT 06520-8023
- Department of Genetics, Yale University School of Medicine, 333 Cedar Street, P.O. Box 208005, New haven, CT 06520-8005
- corresponding author: Department of Pathology, Yale University School of Medicine, P.O. Box 208023, New Haven, CT 06520-8023 phone: (203) 785-2475 FAX: (203) 785-2628
| |
Collapse
|