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Zhu Z, Li S, Yin X, Sun K, Song J, Ren W, Gao L, Zhi K. Review: Protein O-GlcNAcylation regulates DNA damage response: A novel target for cancer therapy. Int J Biol Macromol 2024; 264:130351. [PMID: 38403231 DOI: 10.1016/j.ijbiomac.2024.130351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2024] [Revised: 02/02/2024] [Accepted: 02/19/2024] [Indexed: 02/27/2024]
Abstract
The DNA damage response (DDR) safeguards the stable genetic information inheritance by orchestrating a complex protein network in response to DNA damage. However, this mechanism can often hamper the effectiveness of radiotherapy and DNA-damaging chemotherapy in destroying tumor cells, causing cancer resistance. Inhibiting DDR can significantly improve tumor cell sensitivity to radiotherapy and DNA-damaging chemotherapy. Thus, DDR can be a potential target for cancer treatment. Post-translational modifications (PTMs) of DDR-associated proteins profoundly affect their activity and function by covalently attaching new functional groups. O-GlcNAcylation (O-linked-N-acetylglucosaminylation) is an emerging PTM associated with adding and removing O-linked N-acetylglucosamine to serine and threonine residues of proteins. It acts as a dual sensor for nutrients and stress in the cell and is sensitive to DNA damage. However, the explanation behind the specific role of O-GlcNAcylation in the DDR remains remains to be elucidated. To illustrate the complex relationship between O-GlcNAcylation and DDR, this review systematically describes the role of O-GlcNAcylation in DNA repair, cell cycle, and chromatin. We also discuss the defects of current strategies for targeting O-GlcNAcylation-regulated DDR in cancer therapy and suggest potential directions to address them.
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Affiliation(s)
- Zhuang Zhu
- Department of Oral and Maxillofacial Reconstruction, the Affiliated Hospital of Qingdao University, Qingdao 266555, China; School of Stomatology, Qingdao University, Qingdao 266003, China; Department of Oral and Maxillofacial Surgery, the Affiliated Hospital of Qingdao University, Qingdao 266555, China
| | - Shaoming Li
- Department of Oral and Maxillofacial Reconstruction, the Affiliated Hospital of Qingdao University, Qingdao 266555, China; School of Stomatology, Qingdao University, Qingdao 266003, China; Department of Oral and Maxillofacial Surgery, the Affiliated Hospital of Qingdao University, Qingdao 266555, China
| | - Xiaopeng Yin
- Department of Oral and Maxillofacial Surgery, Central Laboratory of Jinan Stamotological Hospital, Jinan Key Laboratory of Oral Tissue Regeneration, Jinan 250001, Shandong Province, China
| | - Kai Sun
- Department of Oral and Maxillofacial Reconstruction, the Affiliated Hospital of Qingdao University, Qingdao 266555, China; School of Stomatology, Qingdao University, Qingdao 266003, China; Department of Oral and Maxillofacial Surgery, the Affiliated Hospital of Qingdao University, Qingdao 266555, China
| | - Jianzhong Song
- Department of Oral and Maxilloafacial Surgery, People's Hospital of Rizhao, Rizhao, Shandong, China
| | - Wenhao Ren
- Department of Oral and Maxillofacial Reconstruction, the Affiliated Hospital of Qingdao University, Qingdao 266555, China; Department of Oral and Maxillofacial Surgery, the Affiliated Hospital of Qingdao University, Qingdao 266555, China.
| | - Ling Gao
- Department of Oral and Maxillofacial Reconstruction, the Affiliated Hospital of Qingdao University, Qingdao 266555, China; School of Stomatology, Qingdao University, Qingdao 266003, China; Key Lab of Oral Clinical Medicine, the Affiliated Hospital of Qingdao University, Qingdao 266003, China; Department of Oral and Maxillofacial Surgery, the Affiliated Hospital of Qingdao University, Qingdao 266555, China.
| | - Keqian Zhi
- Department of Oral and Maxillofacial Reconstruction, the Affiliated Hospital of Qingdao University, Qingdao 266555, China; School of Stomatology, Qingdao University, Qingdao 266003, China; Key Lab of Oral Clinical Medicine, the Affiliated Hospital of Qingdao University, Qingdao 266003, China; Department of Oral and Maxillofacial Surgery, the Affiliated Hospital of Qingdao University, Qingdao 266555, China.
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Cheng M, Nie Y, Song M, Chen F, Yu Y. Forkhead box O proteins: steering the course of stem cell fate. CELL REGENERATION (LONDON, ENGLAND) 2024; 13:7. [PMID: 38466341 DOI: 10.1186/s13619-024-00190-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2023] [Accepted: 02/26/2024] [Indexed: 03/13/2024]
Abstract
Stem cells are pivotal players in the intricate dance of embryonic development, tissue maintenance, and regeneration. Their behavior is delicately balanced between maintaining their pluripotency and differentiating as needed. Disruptions in this balance can lead to a spectrum of diseases, underscoring the importance of unraveling the complex molecular mechanisms that govern stem cell fate. Forkhead box O (FOXO) proteins, a family of transcription factors, are at the heart of this intricate regulation, influencing a myriad of cellular processes such as survival, metabolism, and DNA repair. Their multifaceted role in steering the destiny of stem cells is evident, as they wield influence over self-renewal, quiescence, and lineage-specific differentiation in both embryonic and adult stem cells. This review delves into the structural and regulatory intricacies of FOXO transcription factors, shedding light on their pivotal roles in shaping the fate of stem cells. By providing insights into the specific functions of FOXO in determining stem cell fate, this review aims to pave the way for targeted interventions that could modulate stem cell behavior and potentially revolutionize the treatment and prevention of diseases.
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Affiliation(s)
- Mengdi Cheng
- Laboratory of Tissue Engineering, College of Life Sciences, Northwest University, Xi'an, China
| | - Yujie Nie
- Laboratory of Tissue Engineering, College of Life Sciences, Northwest University, Xi'an, China
| | - Min Song
- Laboratory of Tissue Engineering, College of Life Sciences, Northwest University, Xi'an, China
| | - Fulin Chen
- Laboratory of Tissue Engineering, College of Life Sciences, Northwest University, Xi'an, China
- Provincial Key Laboratory of Biotechnology of Shaanxi, Northwest University, Xi'an, China
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, School of Medicine, Northwest University, Xi'an, China
| | - Yuan Yu
- Laboratory of Tissue Engineering, College of Life Sciences, Northwest University, Xi'an, China.
- Provincial Key Laboratory of Biotechnology of Shaanxi, Northwest University, Xi'an, China.
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, School of Medicine, Northwest University, Xi'an, China.
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3
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Wu M, Jiang H, Li Q, Liu Y, Zhang H, Li X, Shao Z. OGT-1 regulates synaptic assembly through the insulin signaling pathway. J Cell Biochem 2023; 124:1919-1930. [PMID: 37991448 DOI: 10.1002/jcb.30497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 10/21/2023] [Accepted: 11/01/2023] [Indexed: 11/23/2023]
Abstract
The formation and maintenance of synapses are precisely regulated, and the misregulation often leads to neurodevelopmental or neurodegenerative disorders. Besides intrinsic genetically encoded signaling pathways, synaptic structure and function are also regulated by extrinsic factors, such as nutrients. O-GlcNAc transferase (OGT), a nutrient sensor, is abundant in the nervous system and required for synaptic plasticity, learning, and memory. However, whether OGT is involved in synaptic development and the mechanism underlying the process are largely unknown. In this study, we found that OGT-1, the OGT homolog in C. elegans, regulates the presynaptic assembly in AIY interneurons. The insulin receptor DAF-2 acts upstream of OGT-1 to promote the presynaptic assembly by positively regulating the expression of ogt-1. This insulin-OGT-1 axis functions most likely by regulating neuronal activity. In this study, we elucidated a novel mechanism for synaptic development, and provided a potential link between synaptic development and insulin-related neurological disorders.
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Affiliation(s)
- Mengting Wu
- Department of Neurosurgery, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Huihui Jiang
- Department of Neurosurgery, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Qian Li
- Department of Neurosurgery, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Yunhe Liu
- Department of Neurosurgery, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Hongjun Zhang
- Department of Neurosurgery, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Xuekun Li
- School of Medicine, The Children's Hospital, Zhejiang University, Hangzhou, China
- School of Medicine, The Institute of Translational Medicine, Zhejiang University, Hangzhou, China
- National Clinical Research Center for Child Health, Hangzhou, China
- Zhejiang University Cancer Center, Zhejiang University, Hangzhou, China
| | - Zhiyong Shao
- Department of Neurosurgery, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Zhongshan Hospital, Fudan University, Shanghai, China
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4
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Yue Z, Yu Y, Gao B, Wang D, Sun H, Feng Y, Ma Z, Xie X. Advances in protein glycosylation and its role in tissue repair and regeneration. Glycoconj J 2023; 40:355-373. [PMID: 37097318 DOI: 10.1007/s10719-023-10117-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2022] [Revised: 04/10/2023] [Accepted: 04/16/2023] [Indexed: 04/26/2023]
Abstract
After tissue damage, a series of molecular and cellular events are initiated to promote tissue repair and regeneration to restore its original structure and function. These events include inter-cell communication, cell proliferation, cell migration, extracellular matrix differentiation, and other critical biological processes. Glycosylation is the crucial conservative and universal post-translational modification in all eukaryotic cells [1], with influential roles in intercellular recognition, regulation, signaling, immune response, cellular transformation, and disease development. Studies have shown that abnormally glycosylation of proteins is a well-recognized feature of cancer cells, and specific glycan structures are considered markers of tumor development. There are many studies on gene expression and regulation during tissue repair and regeneration. Still, there needs to be more knowledge of complex carbohydrates' effects on tissue repair and regeneration, such as glycosylation. Here, we present a review of studies investigating protein glycosylation in the tissue repair and regeneration process.
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Affiliation(s)
- Zhongyu Yue
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, College of Life Science, Northwest University, Xi'an, China
| | - Yajie Yu
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, College of Life Science, Northwest University, Xi'an, China
| | - Boyuan Gao
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, College of Life Science, Northwest University, Xi'an, China
| | - Du Wang
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, College of Life Science, Northwest University, Xi'an, China
| | - Hongxiao Sun
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, College of Life Science, Northwest University, Xi'an, China
| | - Yue Feng
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, College of Life Science, Northwest University, Xi'an, China
| | - Zihan Ma
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, College of Life Science, Northwest University, Xi'an, China
| | - Xin Xie
- Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, College of Life Science, Northwest University, Xi'an, China.
- GeWu Medical Research Institute (GMRI), Xi'an, China.
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5
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Konzman D, Fukushige T, Dagnachew M, Krause M, Hanover JA. O-GlcNAc transferase plays a non-catalytic role in C. elegans male fertility. PLoS Genet 2022; 18:e1010273. [PMID: 36383567 PMCID: PMC9710795 DOI: 10.1371/journal.pgen.1010273] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Revised: 11/30/2022] [Accepted: 11/08/2022] [Indexed: 11/17/2022] Open
Abstract
Animal behavior is influenced by the competing drives to maintain energy and to reproduce. The balance between these evolutionary pressures and how nutrient signaling pathways intersect with mating remains unclear. The nutrient sensor O-GlcNAc transferase, which post-translationally modifies intracellular proteins with a single monosaccharide, is responsive to cellular nutrient status and regulates diverse biological processes. Though essential in most metazoans, O-GlcNAc transferase (ogt-1) is dispensable in Caenorhabditis elegans, allowing genetic analysis of its physiological roles. Compared to control, ogt-1 males had a four-fold reduction in mean offspring, with nearly two thirds producing zero progeny. Interestingly, we found that ogt-1 males transferred sperm less often, and virgin males had reduced sperm count. ogt-1 males were also less likely to engage in mate-searching and mate-response behaviors. Surprisingly, we found normal fertility for males with hypodermal expression of ogt-1 and for ogt-1 strains with catalytic-dead mutations. This suggests OGT-1 serves a non-catalytic function in the hypodermis impacting male fertility and mating behavior. This study builds upon research on the nutrient sensor O-GlcNAc transferase and demonstrates a role it plays in the interplay between the evolutionary drives for reproduction and survival.
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Affiliation(s)
- Daniel Konzman
- Laboratory of Cellular and Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
- Department of Biology, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Tetsunari Fukushige
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Mesgana Dagnachew
- Laboratory of Cellular and Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Michael Krause
- Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - John A. Hanover
- Laboratory of Cellular and Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
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Nutrient sensing pathways regulating adult reproductive diapause in C. elegans. PLoS One 2022; 17:e0274076. [PMID: 36112613 PMCID: PMC9480990 DOI: 10.1371/journal.pone.0274076] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Accepted: 08/22/2022] [Indexed: 11/19/2022] Open
Abstract
Genetic and environmental manipulations, such as dietary restriction, can improve both health span and lifespan in a wide range of organisms, including humans. Changes in nutrient intake trigger often overlapping metabolic pathways that can generate distinct or even opposite outputs depending on several factors, such as when dietary restriction occurs in the lifecycle of the organism or the nature of the changes in nutrients. Due to the complexity of metabolic pathways and the diversity in outputs, the underlying mechanisms regulating diet-associated pro-longevity are not yet well understood. Adult reproductive diapause (ARD) in the model organism Caenorhabditis elegans is a dietary restriction model that is associated with lengthened lifespan and reproductive potential. To explore the metabolic pathways regulating ARD in greater depth, we performed a candidate-based genetic screen analyzing select nutrient-sensing pathways to determine their contribution to the regulation of ARD. Focusing on the three phases of ARD (initiation, maintenance, and recovery), we found that ARD initiation is regulated by fatty acid metabolism, sirtuins, AMPK, and the O-linked N-acetyl glucosamine (O-GlcNAc) pathway. Although ARD maintenance was not significantly influenced by the nutrient sensors in our screen, we found that ARD recovery was modulated by energy sensing, stress response, insulin-like signaling, and the TOR pathway. Further investigation of downstream targets of NHR-49 suggest the transcription factor influences ARD initiation through the fatty acid β-oxidation pathway. Consistent with these findings, our analysis revealed a change in levels of neutral lipids associated with ARD entry defects. Our findings identify conserved genetic pathways required for ARD entry and recovery and uncover genetic interactions that provide insight into the role of OGT and OGA.
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Ahmad W. Glucose enrichment impair neurotransmission and induce Aβ oligomerization that cannot be reversed by manipulating O-β-GlcNAcylation in the C. elegans model of Alzheimer's disease. J Nutr Biochem 2022; 108:109100. [PMID: 35779795 DOI: 10.1016/j.jnutbio.2022.109100] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Revised: 02/27/2022] [Accepted: 06/08/2022] [Indexed: 01/17/2023]
Abstract
Amyloid beta (Aβ) plaques formation and impaired neurotransmission and neuronal behaviors are primary hallmarks of Alzheimer's disease (AD) that are further associated with impaired glucose metabolism in elderly AD's patients. However, the exact role of glucose metabolism on disease progression has not been elucidated yet. In this study, the effect of glucose on Aβ-mediated toxicity, neurotransmission and neuronal behaviors has been investigated using a C. elegans model system expressing human Aβ. In addition to regular diet, worms expressing Aβ were supplemented with different concentrations of glucose and glycerol and 5 mM 2-deoxyglucose to draw any conclusions. Addition of glucose to the growth medium delayed Aβ-associated paralysis, promoted abnormal body shapes and movement, unable to restore impaired acetylcholine neurotransmission, inhibited egg laying and hatching in pre-existing Aβ-mediated pathology. The harmful effects of glucose may associate with an increase in toxic Aβ oligomers and impaired neurotransmission. O-β-GlcNAcylation (O-GlcNAc), a well-known post-translational modification is directly associated with glucose metabolism and has been found to ameliorates the Aβ- toxicity. We reasoned that glucose addition might induce O-GlcNAc, thereby protect against Aβ. Contrary to our expectations, induced glucose levels were not protective. Increasing O-GlcNAc, either with Thiamet-G (TMG) or by suppressing the O-GlcNAcase (oga-1) gene does interfere with and, therefore, reduce Aβ- toxicity but not in the presence of high glucose. The effects of glucose cannot be effectively managed by manipulating O-GlcNAc in AD models of C. elegans. Our observations suggest that glucose enrichment is unlikely to be an appropriate therapy to minimize AD progression.
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Affiliation(s)
- Waqar Ahmad
- School of Biological Sciences, the University of Queensland, Brisbane 4072, Australia.
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Abstract
Post-translational modification with O-linked β-N-acetylglucosamine (O-GlcNAc), a process referred to as O-GlcNAcylation, occurs on a vast variety of proteins. Mounting evidence in the past several decades has clearly demonstrated that O-GlcNAcylation is a unique and ubiquitous modification. Reminiscent of a code, protein O-GlcNAcylation functions as a crucial regulator of nearly all cellular processes studied. The primary aim of this review is to summarize the developments in our understanding of myriad protein substrates modified by O-GlcNAcylation from a systems perspective. Specifically, we provide a comprehensive survey of O-GlcNAcylation in multiple species studied, including eukaryotes (e.g., protists, fungi, plants, Caenorhabditis elegans, Drosophila melanogaster, murine, and human), prokaryotes, and some viruses. We evaluate features (e.g., structural properties and sequence motifs) of O-GlcNAc modification on proteins across species. Given that O-GlcNAcylation functions in a species-, tissue-/cell-, protein-, and site-specific manner, we discuss the functional roles of O-GlcNAcylation on human proteins. We focus particularly on several classes of relatively well-characterized human proteins (including transcription factors, protein kinases, protein phosphatases, and E3 ubiquitin-ligases), with representative O-GlcNAc site-specific functions presented. We hope the systems view of the great endeavor in the past 35 years will help demystify the O-GlcNAc code and lead to more fascinating studies in the years to come.
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Affiliation(s)
- Junfeng Ma
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Georgetown University, Washington, DC 20057, United States
| | - Chunyan Hou
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Georgetown University, Washington, DC 20057, United States
| | - Ci Wu
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Georgetown University, Washington, DC 20057, United States
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Wu J, Liu J, Lapenta K, Desrouleaux R, Li MD, Yang X. Regulation of the urea cycle by CPS1 O-GlcNAcylation in response to dietary restriction and aging. J Mol Cell Biol 2022; 14:6548195. [PMID: 35285892 PMCID: PMC9254885 DOI: 10.1093/jmcb/mjac016] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2021] [Revised: 02/20/2022] [Accepted: 03/10/2022] [Indexed: 12/02/2022] Open
Abstract
O-linked N-acetyl-glucosamine glycosylation (O-GlcNAcylation) of intracellular proteins is a dynamic process broadly implicated in age-related disease, yet it remains uncharacterized whether and how O-GlcNAcylation contributes to the natural aging process. O-GlcNAc transferase (OGT) and the opposing enzyme O-GlcNAcase (OGA) control this nutrient-sensing protein modification in cells. Here, we show that global O-GlcNAc levels are increased in multiple tissues of aged mice. In aged liver, carbamoyl phosphate synthetase 1 (CPS1) is among the most heavily O-GlcNAcylated proteins. CPS1 O-GlcNAcylation is reversed by calorie restriction and is sensitive to genetic and pharmacological manipulations of the O-GlcNAc pathway. High glucose stimulates CPS1 O-GlcNAcylation and inhibits CPS1 activity. Liver-specific deletion of OGT potentiates CPS1 activity and renders CPS1 irresponsive to further stimulation by a prolonged fasting. Our results identify CPS1 O-GlcNAcylation as a key nutrient-sensing regulatory step in the urea cycle during aging and dietary restriction, implying a role for mitochondrial O-GlcNAcylation in nutritional regulation of longevity.
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Affiliation(s)
- Jing Wu
- Department of Comparative Medicine, Department of Cellular and Molecular Physiology, and Yale Center for Molecular and Systems Metabolism, Yale University School of Medicine, New Haven, CT 06520, USA
- School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, China
| | - Jiayu Liu
- Department of Comparative Medicine, Department of Cellular and Molecular Physiology, and Yale Center for Molecular and Systems Metabolism, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Kalina Lapenta
- Department of Comparative Medicine, Department of Cellular and Molecular Physiology, and Yale Center for Molecular and Systems Metabolism, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Reina Desrouleaux
- Department of Comparative Medicine, Department of Cellular and Molecular Physiology, and Yale Center for Molecular and Systems Metabolism, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Min-Dian Li
- Department of Comparative Medicine, Department of Cellular and Molecular Physiology, and Yale Center for Molecular and Systems Metabolism, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Xiaoyong Yang
- Department of Comparative Medicine, Department of Cellular and Molecular Physiology, and Yale Center for Molecular and Systems Metabolism, Yale University School of Medicine, New Haven, CT 06520, USA
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10
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Cruz‐Ruiz P, Hernando‐Rodríguez B, Pérez‐Jiménez MM, Rodríguez‐Palero MJ, Martínez‐Bueno MD, Pla A, Gatsi R, Artal‐Sanz M. Prohibitin depletion extends lifespan of a TORC2/SGK-1 mutant through autophagy and the mitochondrial UPR. Aging Cell 2021; 20:e13359. [PMID: 33939875 PMCID: PMC8135086 DOI: 10.1111/acel.13359] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 03/05/2021] [Accepted: 03/25/2021] [Indexed: 12/22/2022] Open
Abstract
Mitochondrial prohibitins (PHB) are highly conserved proteins with a peculiar effect on lifespan. While PHB depletion shortens lifespan of wild‐type animals, it enhances longevity of a plethora of metabolically compromised mutants, including target of rapamycin complex 2 (TORC2) mutants sgk‐1 and rict‐1. Here, we show that sgk‐1 mutants have impaired mitochondrial homeostasis, lipogenesis and yolk formation, plausibly due to alterations in membrane lipid and sterol homeostasis. Remarkably, all these features are suppressed by PHB depletion. Our analysis shows the requirement of SRBP1/SBP‐1 for the lifespan extension of sgk‐1 mutants and the further extension conferred by PHB depletion. Moreover, although the mitochondrial unfolded protein response (UPRmt) and autophagy are induced in sgk‐1 mutants and upon PHB depletion, they are dispensable for lifespan. However, the enhanced longevity caused by PHB depletion in sgk‐1 mutants requires both, the UPRmt and autophagy, but not mitophagy. We hypothesize that UPRmt induction upon PHB depletion extends lifespan of sgk‐1 mutants through autophagy and probably modulation of lipid metabolism.
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Affiliation(s)
- Patricia Cruz‐Ruiz
- Andalusian Centre for Developmental Biology Consejo Superior de Investigaciones Científicas/Junta de Andalucía/Universidad Pablo de Olavide Seville Spain
- Department of Molecular Biology and Biochemical Engineering Universidad Pablo de Olavide Seville Spain
| | - Blanca Hernando‐Rodríguez
- Andalusian Centre for Developmental Biology Consejo Superior de Investigaciones Científicas/Junta de Andalucía/Universidad Pablo de Olavide Seville Spain
- Department of Molecular Biology and Biochemical Engineering Universidad Pablo de Olavide Seville Spain
| | - Mercedes M. Pérez‐Jiménez
- Andalusian Centre for Developmental Biology Consejo Superior de Investigaciones Científicas/Junta de Andalucía/Universidad Pablo de Olavide Seville Spain
- Department of Molecular Biology and Biochemical Engineering Universidad Pablo de Olavide Seville Spain
| | - María Jesús Rodríguez‐Palero
- Andalusian Centre for Developmental Biology Consejo Superior de Investigaciones Científicas/Junta de Andalucía/Universidad Pablo de Olavide Seville Spain
- Department of Molecular Biology and Biochemical Engineering Universidad Pablo de Olavide Seville Spain
| | - Manuel D. Martínez‐Bueno
- Andalusian Centre for Developmental Biology Consejo Superior de Investigaciones Científicas/Junta de Andalucía/Universidad Pablo de Olavide Seville Spain
- Department of Molecular Biology and Biochemical Engineering Universidad Pablo de Olavide Seville Spain
| | - Antoni Pla
- Andalusian Centre for Developmental Biology Consejo Superior de Investigaciones Científicas/Junta de Andalucía/Universidad Pablo de Olavide Seville Spain
- Department of Molecular Biology and Biochemical Engineering Universidad Pablo de Olavide Seville Spain
| | - Roxani Gatsi
- Andalusian Centre for Developmental Biology Consejo Superior de Investigaciones Científicas/Junta de Andalucía/Universidad Pablo de Olavide Seville Spain
- Department of Molecular Biology and Biochemical Engineering Universidad Pablo de Olavide Seville Spain
| | - Marta Artal‐Sanz
- Andalusian Centre for Developmental Biology Consejo Superior de Investigaciones Científicas/Junta de Andalucía/Universidad Pablo de Olavide Seville Spain
- Department of Molecular Biology and Biochemical Engineering Universidad Pablo de Olavide Seville Spain
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11
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Martinez M, Renuse S, Kreimer S, O'Meally R, Natov P, Madugundu AK, Nirujogi RS, Tahir R, Cole R, Pandey A, Zachara NE. Quantitative Proteomics Reveals that the OGT Interactome Is Remodeled in Response to Oxidative Stress. Mol Cell Proteomics 2021; 20:100069. [PMID: 33716169 PMCID: PMC8079276 DOI: 10.1016/j.mcpro.2021.100069] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 01/26/2021] [Accepted: 03/04/2021] [Indexed: 12/17/2022] Open
Abstract
The dynamic modification of specific serine and threonine residues of intracellular proteins by O-linked N-acetyl-β-D-glucosamine (O-GlcNAc) mitigates injury and promotes cytoprotection in a variety of stress models. The O-GlcNAc transferase (OGT) and the O-GlcNAcase are the sole enzymes that add and remove O-GlcNAc, respectively, from thousands of substrates. It remains unclear how just two enzymes can be specifically controlled to affect glycosylation of target proteins and signaling pathways both basally and in response to stress. Several lines of evidence suggest that protein interactors regulate these responses by affecting OGT and O-GlcNAcase activity, localization, and substrate specificity. To provide insight into the mechanisms by which OGT function is controlled, we have used quantitative proteomics to define OGT's basal and stress-induced interactomes. OGT and its interaction partners were immunoprecipitated from OGT WT, null, and hydrogen peroxide-treated cell lysates that had been isotopically labeled with light, medium, and heavy lysine and arginine (stable isotopic labeling of amino acids in cell culture). In total, more than 130 proteins were found to interact with OGT, many of which change their association upon hydrogen peroxide stress. These proteins include the major OGT cleavage and glycosylation substrate, host cell factor 1, which demonstrated a time-dependent dissociation after stress. To validate less well-characterized interactors, such as glyceraldehyde 3-phosphate dehydrogenase and histone deacetylase 1, we turned to parallel reaction monitoring, which recapitulated our discovery-based stable isotopic labeling of amino acids in cell culture approach. Although the majority of proteins identified are novel OGT interactors, 64% of them are previously characterized glycosylation targets that contain varied domain architecture and function. Together these data demonstrate that OGT interacts with unique and specific interactors in a stress-responsive manner.
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Affiliation(s)
- Marissa Martinez
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States; Currently at Foghorn Therapeutics, Cambridge, Massachusetts, United States
| | - Santosh Renuse
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States; McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States; Currently at the Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, United States; Currently at the Center for Individualized Medicine, Mayo Clinic, Rochester, Minnesota, United States
| | - Simion Kreimer
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States; The Mass Spectrometry and Proteomics Facility, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA; Currently at the Advanced Clinical Biosystems Institute, Smidt Heart institute, Cedars Sinai Medical Center, Los Angeles, California, USA
| | - Robert O'Meally
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States; The Mass Spectrometry and Proteomics Facility, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Peter Natov
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States; Currently at the Department of Internal Medicine, Yale New Haven Hospital, Yale School of Medicine, New Haven, Connecticut, USA
| | - Anil K Madugundu
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States; McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States; Currently at the Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, United States
| | - Raja Sekhar Nirujogi
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States; McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States; Currently at the Medical Research Council (MRC) Protein Phosphorylation and Ubiquitylation Unit, School of Life Sciences, University of Dundee, Dundee, UK
| | - Raiha Tahir
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States; Biochemistry, Cellular and Molecular Biology Graduate Program, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States; Currently at Ginkgo Bioworks, Massachusetts, United States
| | - Robert Cole
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States; The Mass Spectrometry and Proteomics Facility, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Akhilesh Pandey
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States; McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States; Currently at the Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, United States; Currently at the Center for Individualized Medicine, Mayo Clinic, Rochester, Minnesota, United States; Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - Natasha E Zachara
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States; Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States.
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12
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Itkonen HM, Loda M, Mills IG. O-GlcNAc Transferase - An Auxiliary Factor or a Full-blown Oncogene? Mol Cancer Res 2021; 19:555-564. [PMID: 33472950 DOI: 10.1158/1541-7786.mcr-20-0926] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 12/05/2020] [Accepted: 01/07/2021] [Indexed: 11/16/2022]
Abstract
The β-linked N-acetyl-d-glucosamine (GlcNAc) is a posttranslational modification of serine and threonine residues catalyzed by the enzyme O-GlcNAc transferase (OGT). Increased OGT expression is a feature of most human cancers and inhibition of OGT decreases cancer cell proliferation. Antiproliferative effects are attributed to posttranslational modifications of known regulators of cancer cell proliferation, such as MYC, FOXM1, and EZH2. In general, OGT amplifies cell-specific phenotype, for example, OGT overexpression enhances reprogramming efficiency of mouse embryonic fibroblasts into stem cells. Genome-wide screens suggest that certain cancers are particularly dependent on OGT, and understanding these addictions is important when considering OGT as a target for cancer therapy. The O-GlcNAc modification is involved in most cellular processes, which raises concerns of on-target undesirable effects of OGT-targeting therapy. Yet, emerging evidence suggest that, much like proteasome inhibitors, specific compounds targeting OGT elicit selective antiproliferative effects in cancer cells, and can prime malignant cells to other treatments. It is, therefore, essential to gain mechanistic insights on substrate specificity for OGT, develop reagents to more specifically enrich for O-GlcNAc-modified proteins, identify O-GlcNAc "readers," and develop OGT small-molecule inhibitors. Here, we review the relevance of OGT in cancer progression and the potential targeting of this metabolic enzyme as a putative oncogene.
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Affiliation(s)
- Harri M Itkonen
- Department of Biochemistry and Developmental Biology, Faculty of Medicine, University of Helsinki, Helsinki, Finland.
| | - Massimo Loda
- Department of Pathology and Laboratory Medicine, Weill Cornell Medicine, New York-Presbyterian Hospital, New York, New York.,The Broad Institute of Harvard and MIT, Cambridge, Massachusetts.,The New York Genome Center, New York, New York
| | - Ian G Mills
- Nuffield Department of Surgical Sciences, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom. .,PCUK/Movember Centre of Excellence for Prostate Cancer Research, Patrick G Johnston Centre, for Cancer Research (PGJCCR), Queen's University Belfast, Belfast, United Kingdom
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13
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Su L, Zhao T, Li H, Li H, Su X, Ba X, Zhang Y, Huang B, Lu J, Li X. ELT-2 promotes O-GlcNAc transferase OGT-1 expression to modulate Caenorhabditis elegans lifespan. J Cell Biochem 2020; 121:4898-4907. [PMID: 32628333 DOI: 10.1002/jcb.29817] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Revised: 06/08/2020] [Accepted: 06/17/2020] [Indexed: 11/12/2022]
Abstract
O-GlcNAc transferase (OGT) is the enzyme catalyzing protein O-GlcNAcylation by addition of a single O-linked-β-N-acetylglucosamine molecule (O-GlcNAc) to nuclear and cytoplasmic targets, and it uses uridine diphosphate-N-acetylglucosamine (UDP-GlcNAc) as a donor. As UDP-GlcNAc is the final product of the nutrient-sensing hexosamine signaling pathway, overexpression or knockout of ogt in mammals or invertebrate models influences cellular nutrient-response signals and increases susceptibility to chronic diseases of aging. Evidence shows that OGT expression levels decrease in tissues of older mice and rats. However, how OGT expression is modulated in the aging process remains poorly understood. In Caenorhabditis elegans, the exclusive mammalian OGT ortholog OGT-1 is crucial for lifespan control. Here, we observe that worm OGT-1 expression gradually reduces during aging. By combining prediction via the "MATCH" algorithm and luciferase reporter assays, GATA factor ELT-2, the homolog of human GATA4, is identified as a transcriptional factor driving OGT-1 expression. Chromatin immunoprecipitation-quantitative polymerase chain reaction and electrophoretic mobility shift assays show ELT-2 directly binds to and activates the ogt-1 promoter. Knockdown of elt-2 decreases the global O-GlcNAc modification level and reduces the lifespan of wild-type worms. The reduction in lifespan caused by elt-2 RNA interference is abrogated by the loss of ogt-1. These results imply that GATA factors are able to activate OGT expression, which could be beneficial for longevity and the development of therapeutic treatment for aging-related diseases.
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Affiliation(s)
- Liangping Su
- The Key Laboratory of Molecular Epigenetics of the Ministry of Education, Northeast Normal University, Changchun, China
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Medical Research Center, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Tingting Zhao
- The Institute of Genetics and Cytology, Northeast Normal University, Changchun, China
| | - Hongyuan Li
- The Key Laboratory of Molecular Epigenetics of the Ministry of Education, Northeast Normal University, Changchun, China
- Laboratory of Chemical Biology, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, China
| | - Hongmei Li
- The Key Laboratory of Molecular Epigenetics of the Ministry of Education, Northeast Normal University, Changchun, China
| | - Xin Su
- The Key Laboratory of Molecular Epigenetics of the Ministry of Education, Northeast Normal University, Changchun, China
| | - Xueqing Ba
- The Key Laboratory of Molecular Epigenetics of the Ministry of Education, Northeast Normal University, Changchun, China
| | - Yu Zhang
- The Institute of Genetics and Cytology, Northeast Normal University, Changchun, China
| | - Baiqu Huang
- The Institute of Genetics and Cytology, Northeast Normal University, Changchun, China
| | - Jun Lu
- The Institute of Genetics and Cytology, Northeast Normal University, Changchun, China
| | - Xiaoxue Li
- The Key Laboratory of Molecular Epigenetics of the Ministry of Education, Northeast Normal University, Changchun, China
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14
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Kremer J, Brendel C, Mack EKM, Mack HID. Expression of β-1,4-galactosyltransferases during Aging in Caenorhabditis elegans. Gerontology 2020; 66:571-581. [PMID: 33171474 DOI: 10.1159/000510722] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Accepted: 08/03/2020] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Altered plasma activity of β-1,4-galac-tosyl-transferases (B4GALTs) is a novel candidate biomarker of human aging. B4GALT1 is assumed to be largely responsible for this activity increase, but how it modulates the aging process is unclear at present. OBJECTIVES To determine how expression of B4GALT1 and other B4GALT enzymes changes during aging of an experimentally tractable model organism, Caenorhabditis elegans. METHODS Targeted analysis of mRNA levels of all 3 C. elegans B4GALT family members was performed by qPCR in wild-type and in long-lived daf-2 (insulin/IGF1-like receptor)-deficient or germline-deficient animals. RESULTS bre-4 (B4GALT1/2/3/4) is the only B4GALT whose expression increases during aging in wild-type worms. In addition, bre-4 levels also rise during aging in long-lived daf-2-deficient worms, but not in animals that are long-lived due to the lack of germline stem cells. On the other hand, expression of sqv-3 (B4GALT7) and of W02B12.11 (B4GALT5/6) appears decreased or constant, respectively, in all backgrounds during aging. CONCLUSIONS The age-dependent bre-4 mRNA increase in C. elegans parallels the age-dependent B4GALT activity increase in humans and is consistent with C. elegans being a suitable experimental organism to define potentially conserved roles of B4GALT1 during aging.
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Affiliation(s)
- Jennifer Kremer
- Department of Hematology, Oncology and Immunology, Philipps-University Marburg, and University Hospital Gießen and Marburg, Marburg, Germany
| | - Cornelia Brendel
- Department of Hematology, Oncology and Immunology, Philipps-University Marburg, and University Hospital Gießen and Marburg, Marburg, Germany
| | - Elisabeth Karin Maria Mack
- Department of Hematology, Oncology and Immunology, Philipps-University Marburg, and University Hospital Gießen and Marburg, Marburg, Germany,
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15
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Urso SJ, Comly M, Hanover JA, Lamitina T. The O-GlcNAc transferase OGT is a conserved and essential regulator of the cellular and organismal response to hypertonic stress. PLoS Genet 2020; 16:e1008821. [PMID: 33006972 PMCID: PMC7556452 DOI: 10.1371/journal.pgen.1008821] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 10/14/2020] [Accepted: 08/25/2020] [Indexed: 12/12/2022] Open
Abstract
The conserved O-GlcNAc transferase OGT O-GlcNAcylates serine and threonine residues of intracellular proteins to regulate their function. OGT is required for viability in mammalian cells, but its specific roles in cellular physiology are poorly understood. Here we describe a conserved requirement for OGT in an essential aspect of cell physiology: the hypertonic stress response. Through a forward genetic screen in Caenorhabditis elegans, we discovered OGT is acutely required for osmoprotective protein expression and adaptation to hypertonic stress. Gene expression analysis shows that ogt-1 functions through a post-transcriptional mechanism. Human OGT partially rescues the C. elegans phenotypes, suggesting that the osmoregulatory functions of OGT are ancient. Intriguingly, expression of O-GlcNAcylation-deficient forms of human or worm OGT rescue the hypertonic stress response phenotype. However, expression of an OGT protein lacking the tetracopeptide repeat (TPR) domain does not rescue. Our findings are among the first to demonstrate a specific physiological role for OGT at the organismal level and demonstrate that OGT engages in important molecular functions outside of its well described roles in post-translational O-GlcNAcylation of intracellular proteins.
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Affiliation(s)
- Sarel J. Urso
- Graduate Program in Cell Biology and Molecular Physiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States of America
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States of America
| | - Marcella Comly
- Laboratory of Cellular and Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institute of Health, Bethesda, MD, United States of America
| | - John A. Hanover
- Laboratory of Cellular and Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institute of Health, Bethesda, MD, United States of America
| | - Todd Lamitina
- Graduate Program in Cell Biology and Molecular Physiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States of America
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States of America
- Division of Child Neurology, Department of Pediatrics, Children’s Hospital of Pittsburgh, Pittsburgh, PA, United States of America
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16
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Age-related loss of neural stem cell O-GlcNAc promotes a glial fate switch through STAT3 activation. Proc Natl Acad Sci U S A 2020; 117:22214-22224. [PMID: 32848054 PMCID: PMC7486730 DOI: 10.1073/pnas.2007439117] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Depletion of the neural stem cell (NSC) pool is a major driver of age-related regenerative decline in the hippocampus. While increased quiescence is a major contributor to this decline, NSCs can also undergo terminal differentiation into astrocytes, thus restricting the stem cell pool. The mechanisms underlying this fate switch and their relation to age-related regenerative decline have not yet been fully elucidated. In this study, we report an age-related decline in NSC O-GlcNAcylation, coincident with reduced neurogenesis and increased gliogenesis. We identify loss of O-GlcNAcylation at STAT3 T717 in the hippocampus with age, and demonstrate that O-GlcNAcylation of this site is a critical determinant of NSC fate. Our work expands our understanding of how posttranslational modifications influence the aging brain. Increased neural stem cell (NSC) quiescence is a major determinant of age-related regenerative decline in the adult hippocampus. However, a coextensive model has been proposed in which division-coupled conversion of NSCs into differentiated astrocytes restrict the stem cell pool with age. Here we report that age-related loss of the posttranslational modification, O-linked β-N-acetylglucosamine (O-GlcNAc), in NSCs promotes a glial fate switch. We detect an age-dependent decrease in NSC O-GlcNAc levels coincident with decreased neurogenesis and increased gliogenesis in the mature hippocampus. Mimicking an age-related loss of NSC O-GlcNAcylation in young mice reduces neurogenesis, increases astrocyte differentiation, and impairs associated cognitive function. Using RNA-sequencing of primary NSCs following decreased O-GlcNAcylation, we detected changes in the STAT3 signaling pathway indicative of glial differentiation. Moreover, using O-GlcNAc–specific mass spectrometry analysis of the aging hippocampus, together with an in vitro site-directed mutagenesis approach, we identify loss of STAT3 O-GlcNAc at Threonine 717 as a driver of astrocyte differentiation. Our data identify the posttranslational modification, O-GlcNAc, as a key molecular regulator of regenerative decline underlying an age-related NSC fate switch.
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17
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Abstract
Glycosylation refers to the covalent attachment of sugar residues to a protein or lipid, and the biological importance of this modification has been widely recognized. While glycosylation in mammals is being extensively investigated, lower level animals such as invertebrates have not been adequately interrogated for their glycosylation. The rich diversity of invertebrate species, the increased database of sequenced invertebrate genomes and the time and cost efficiency of raising and experimenting on these species have enabled a handful of the species to become excellent model organisms, which have been successfully used as tools for probing various biologically interesting problems. Investigation on invertebrate glycosylation, especially on model organisms, not only expands the structural and functional knowledgebase, but also can facilitate deeper understanding on the biological functions of glycosylation in higher organisms. Here, we reviewed the research advances in invertebrate glycosylation, including N- and O-glycosylation, glycosphingolipids and glycosaminoglycans. The aspects of glycan biosynthesis, structures and functions are discussed, with a focus on the model organisms Drosophila and Caenorhabditis. Analytical strategies for the glycans and glycoconjugates are also summarized.
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Affiliation(s)
- Feifei Zhu
- 1 Institute of Life Sciences, Jiangsu University , Zhenjiang 212013 , People's Republic of China.,2 School of Food and Biological Engineering, Jiangsu University , Zhenjiang 212013 , People's Republic of China
| | - Dong Li
- 1 Institute of Life Sciences, Jiangsu University , Zhenjiang 212013 , People's Republic of China
| | - Keping Chen
- 1 Institute of Life Sciences, Jiangsu University , Zhenjiang 212013 , People's Republic of China
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18
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Marcel N, Hedrick SM. A key control point in the T cell response to chronic infection and neoplasia: FOXO1. Curr Opin Immunol 2020; 63:51-60. [PMID: 32135399 DOI: 10.1016/j.coi.2020.02.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Revised: 01/29/2020] [Accepted: 02/01/2020] [Indexed: 12/26/2022]
Abstract
T cells able to control neoplasia or chronic infections display a signature gene expression profile similar or identical to that of central memory T cells. These cells have qualities of self-renewal and a plasticity that allow them to repeatedly undergo activation (growth, proliferation, and differentiation), followed by quiescence. It is these qualities that define the ability of T cells to establish an equilibrium with chronic infectious agents, and also preserve the ability of T cells to be re-activated (by checkpoint therapy) in response to malignant cancers. Here we describe distinctions between the forms of inhibition mediated by tumors and persistent viruses, we review the properties of T cells associated with long-term immunity, and we identify the transcription factor, FOXO1, as the control point for a program of gene expression that allows CD8+ T cells to undergo serial reactivation and self-renewal.
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Affiliation(s)
- Nimi Marcel
- Molecular Biology Section, Division of Biological Sciences, Department of Cellular and Molecular Medicine, TATA Institute for Genetics and Society, University of California, San Diego, La Jolla, CA 92093-0377, United States
| | - Stephen M Hedrick
- Molecular Biology Section, Division of Biological Sciences, Department of Cellular and Molecular Medicine, TATA Institute for Genetics and Society, University of California, San Diego, La Jolla, CA 92093-0377, United States.
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19
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Wheatley EG, Albarran E, White CW, Bieri G, Sanchez-Diaz C, Pratt K, Snethlage CE, Ding JB, Villeda SA. Neuronal O-GlcNAcylation Improves Cognitive Function in the Aged Mouse Brain. Curr Biol 2019; 29:3359-3369.e4. [PMID: 31588002 PMCID: PMC7199460 DOI: 10.1016/j.cub.2019.08.003] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Revised: 06/24/2019] [Accepted: 08/01/2019] [Indexed: 12/31/2022]
Abstract
Mounting evidence in animal models indicates potential for rejuvenation of cellular and cognitive functions in the aging brain. However, the ability to utilize this potential is predicated on identifying molecular targets that reverse the effects of aging in vulnerable regions of the brain, such as the hippocampus. The dynamic post-translational modification O-linked N-Acetylglucosamine (O-GlcNAc) has emerged as an attractive target for regulating aging-specific synaptic alterations as well as neurodegeneration. While speculation exists about the role of O-GlcNAc in neurodegenerative conditions, such as Alzheimer’s disease, its role in physiological brain aging remains largely unexplored. Here, we report that countering age-related decreased O-GlcNAc transferase (OGT) expression and O-GlcNAcylation ameliorates cognitive impairments in aged mice. Mimicking an aged condition in young adults by abrogating OGT, using a temporally controlled neuron-specific conditional knockout mouse model, recapitulated cellular and cognitive features of brain aging. Conversely, overexpressing OGT in mature hippocampal neurons using a viral-mediated approach enhanced associative fear memory in young adult mice. Excitingly, in aged mice overexpressing neuronal OGT in the aged hippocampus rescued in part age-related impairments in spatial learning and memory as well as associative fear memory. Our data identify O-GlcNAcylaton as a key molecular mediator promoting cognitive rejuvenation. Wheatley et al. identify O-GlcNAcylation as a key posttranslational modification promoting cognitive rejuvenation. Mimicking age-related decreased neuronal OGT and O-GlcNAc levels in the young hippocampus impaired cognition, while restoring neuronal OGT and O-GlcNAc in the aged hippocampus rejuvenated cognition.
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Affiliation(s)
- Elizabeth G Wheatley
- Department of Anatomy, University of California, San Francisco, San Francisco, CA 94143, USA; Developmental and Stem Cell Biology Graduate Program, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Eddy Albarran
- Neuroscience IDP Program, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Neurosurgery, Stanford University School of Medicine, Palo Alto, CA 94304, USA
| | - Charles W White
- Department of Anatomy, University of California, San Francisco, San Francisco, CA 94143, USA; Developmental and Stem Cell Biology Graduate Program, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Gregor Bieri
- Department of Anatomy, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Cesar Sanchez-Diaz
- Department of Anatomy, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Karishma Pratt
- Department of Anatomy, University of California, San Francisco, San Francisco, CA 94143, USA; Developmental and Stem Cell Biology Graduate Program, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Cedric E Snethlage
- Department of Anatomy, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Jun B Ding
- Neuroscience IDP Program, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Neurosurgery, Stanford University School of Medicine, Palo Alto, CA 94304, USA
| | - Saul A Villeda
- Department of Anatomy, University of California, San Francisco, San Francisco, CA 94143, USA; Developmental and Stem Cell Biology Graduate Program, University of California, San Francisco, San Francisco, CA 94143, USA; Department of Physical Therapy and Rehabilitation Science, University of California, San Francisco, San Francisco, CA 94143, USA; The Eli and Edythe Broad Center for Regeneration Medicine and Stem Cell Research, San Francisco, CA 94143, USA.
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20
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Sheikh MO, Tayyari F, Zhang S, Judge MT, Weatherly DB, Ponce FV, Wells L, Edison AS. Correlations Between LC-MS/MS-Detected Glycomics and NMR-Detected Metabolomics in Caenorhabditis elegans Development. Front Mol Biosci 2019; 6:49. [PMID: 31316996 PMCID: PMC6611444 DOI: 10.3389/fmolb.2019.00049] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2019] [Accepted: 06/11/2019] [Indexed: 01/19/2023] Open
Abstract
This study examined the relationship between glycans, metabolites, and development in C. elegans. Samples of N2 animals were synchronized and grown to five different time points ranging from L1 to a mixed population of adults, gravid adults, and offspring. Each time point was replicated seven times. The samples were each assayed by a large particle flow cytometer (Biosorter) for size distribution data, LC-MS/MS for targeted N- and O-linked glycans, and NMR for metabolites. The same samples were utilized for all measurements, which allowed for statistical correlations between the data. A new protocol was developed to correlate Biosorter developmental data with LC-MS/MS data to obtain stage-specific information of glycans. From the five time points, four distinct sizes of worms were observed from the Biosorter distributions, ranging from the smallest corresponding to L1 to adult animals. A network model was constructed using the four binned sizes of worms as starting nodes and adding glycans and metabolites that had correlations with r ≥ 0.5 to those nodes. The emerging structure of the network showed distinct patterns of N- and O-linked glycans that were consistent with previous studies. Furthermore, some metabolites that were correlated to these glycans and worm sizes showed interesting interactions. Of note, UDP-GlcNAc had strong positive correlations with many O-glycans that were expressed in the largest animals. Similarly, phosphorylcholine correlated with many N-glycans that were expressed in L1 animals.
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Affiliation(s)
- M Osman Sheikh
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, United States
| | - Fariba Tayyari
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, United States
| | - Sicong Zhang
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, United States.,Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, United States
| | - Michael T Judge
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, United States.,Department of Genetics, University of Georgia, Athens, GA, United States
| | - D Brent Weatherly
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, United States
| | - Francesca V Ponce
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, United States
| | - Lance Wells
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, United States.,Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, United States
| | - Arthur S Edison
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, United States.,Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, United States.,Department of Genetics, University of Georgia, Athens, GA, United States.,Institute of Bioinformatics, University of Georgia, Athens, GA, United States
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21
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Scheckhuber CQ. Studying the mechanisms and targets of glycation and advanced glycation end-products in simple eukaryotic model systems. Int J Biol Macromol 2019; 127:85-94. [DOI: 10.1016/j.ijbiomac.2019.01.032] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Revised: 01/07/2019] [Accepted: 01/07/2019] [Indexed: 12/20/2022]
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22
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Nuclear FOXO1 promotes lymphomagenesis in germinal center B cells. Blood 2018; 132:2670-2683. [DOI: 10.1182/blood-2018-06-856203] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Accepted: 10/10/2018] [Indexed: 12/15/2022] Open
Abstract
Abstract
Forkhead box class O1 (FOXO1) acts as a tumor suppressor in solid tumors. The oncogenic phosphoinositide-3-kinase (PI3K) pathway suppresses FOXO1 transcriptional activity by enforcing its nuclear exclusion upon AKT-mediated phosphorylation. We show here abundant nuclear expression of FOXO1 in Burkitt lymphoma (BL), a germinal center (GC) B-cell–derived lymphoma whose pathogenesis is linked to PI3K activation. Recurrent FOXO1 mutations, which prevent AKT targeting and lock the transcription factor in the nucleus, are used by BL to circumvent mutual exclusivity between PI3K and FOXO1 activation. Using genome editing in human and mouse lymphomas in which MYC and PI3K cooperate synergistically in tumor development, we demonstrate proproliferative and antiapoptotic activity of FOXO1 in BL and identify its nuclear localization as an oncogenic event in GC B-cell–derived lymphomagenesis.
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23
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Ardiel EL, McDiarmid TA, Timbers TA, Lee KCY, Safaei J, Pelech SL, Rankin CH. Insights into the roles of CMK-1 and OGT-1 in interstimulus interval-dependent habituation in Caenorhabditis elegans. Proc Biol Sci 2018; 285:rspb.2018.2084. [PMID: 30429311 DOI: 10.1098/rspb.2018.2084] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Accepted: 10/25/2018] [Indexed: 12/19/2022] Open
Abstract
Habituation is a ubiquitous form of non-associative learning observed as a decrement in responding to repeated stimulation that cannot be explained by sensory adaptation or motor fatigue. One of the defining characteristics of habituation is its sensitivity to the rate at which training stimuli are presented-animals habituate faster in response to more rapid stimulation. The molecular mechanisms underlying this interstimulus interval (ISI)-dependent characteristic of habituation remain unknown. In this article, we use behavioural neurogenetic and bioinformatic analyses in the nematode Caenorhabiditis elegans to identify the first molecules that modulate habituation in an ISI-dependent manner. We show that the Caenorhabditis elegans orthologues of Ca2+/calmodulin-dependent kinases CaMK1/4, CMK-1 and O-linked N-acetylglucosamine (O-GlcNAc) transferase, OGT-1, both function in primary sensory neurons to inhibit habituation at short ISIs and promote it at long ISIs. In addition, both cmk-1 and ogt-1 mutants display a rare mechanosensory hyper-responsive phenotype (i.e. larger mechanosensory responses than wild-type). Overall, our work identifies two conserved genes that function in sensory neurons to modulate habituation in an ISI-dependent manner, providing the first insights into the molecular mechanisms underlying the universally observed phenomenon that habituation has different properties when stimuli are delivered at different rates.
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Affiliation(s)
- Evan L Ardiel
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, 2211 Wesbrook Mall, Vancouver, British Columbia, Canada V6T 2B5
| | - Troy A McDiarmid
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, 2211 Wesbrook Mall, Vancouver, British Columbia, Canada V6T 2B5
| | - Tiffany A Timbers
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, 2211 Wesbrook Mall, Vancouver, British Columbia, Canada V6T 2B5
| | - Kirsten C Y Lee
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, 2211 Wesbrook Mall, Vancouver, British Columbia, Canada V6T 2B5
| | - Javad Safaei
- Department of Computer Science, University of British Columbia, 2366 Main Mall, Vancouver, British Columbia, Canada V6T 1Z4
| | - Steven L Pelech
- Department of Medicine, University of British Columbia, 2775 Laurel Street, Vancouver, British Columbia, Canada V5Z 1M9.,Kinexus Bioinformatics Corporation, Suite 1, 8755 Ash Street, Vancouver, British Columbia, Canada V6P 6T3
| | - Catharine H Rankin
- Djavad Mowafaghian Centre for Brain Health, University of British Columbia, 2211 Wesbrook Mall, Vancouver, British Columbia, Canada V6T 2B5 .,Department of Psychology, University of British Columbia, 2136 West Mall, Vancouver, British Columbia, Canada V6T 1Z4
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Chen PH, Chi JT, Boyce M. Functional crosstalk among oxidative stress and O-GlcNAc signaling pathways. Glycobiology 2018; 28:556-564. [PMID: 29548027 PMCID: PMC6054262 DOI: 10.1093/glycob/cwy027] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2017] [Revised: 02/14/2018] [Accepted: 03/13/2018] [Indexed: 12/12/2022] Open
Abstract
In metazoans, thousands of intracellular proteins are modified with O-linked β-N-acetylglucosamine (O-GlcNAc) in response to a wide range of stimuli and stresses. In particular, a complex and evolutionarily conserved interplay between O-GlcNAcylation and oxidative stress has emerged in recent years. Here, we review the current literature on the connections between O-GlcNAc and oxidative stress, with a particular emphasis on major signaling pathways, such as KEAP1/NRF2, FOXO, NFκB, p53 and cell metabolism. Taken together, this work sheds important light on the signaling functions of protein glycosylation and the mechanisms of stress responses alike and illuminates how the two are integrated in animal cell physiology.
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Affiliation(s)
- Po-Han Chen
- Department of Biochemistry
- Department of Molecular Genetics and Microbiology
- Center for Genomic and Computational Biology, Duke University School of Medicine, Durham, NC, USA
| | - Jen-Tsan Chi
- Department of Molecular Genetics and Microbiology
- Center for Genomic and Computational Biology, Duke University School of Medicine, Durham, NC, USA
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25
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Horowitz AM, Villeda SA. Therapeutic potential of systemic brain rejuvenation strategies for neurodegenerative disease. F1000Res 2017; 6:1291. [PMID: 28815019 PMCID: PMC5539850 DOI: 10.12688/f1000research.11437.1] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 07/26/2017] [Indexed: 12/18/2022] Open
Abstract
Neurodegenerative diseases are a devastating group of conditions that cause progressive loss of neuronal integrity, affecting cognitive and motor functioning in an ever-increasing number of older individuals. Attempts to slow neurodegenerative disease advancement have met with little success in the clinic; however, a new therapeutic approach may stem from classic interventions, such as caloric restriction, exercise, and parabiosis. For decades, researchers have reported that these systemic-level manipulations can promote major functional changes that extend organismal lifespan and healthspan. Only recently, however, have the functional effects of these interventions on the brain begun to be appreciated at a molecular and cellular level. The potential to counteract the effects of aging in the brain, in effect rejuvenating the aged brain, could offer broad therapeutic potential to combat dementia-related neurodegenerative disease in the elderly. In particular, results from heterochronic parabiosis and young plasma administration studies indicate that pro-aging and rejuvenating factors exist in the circulation that can independently promote or reverse age-related phenotypes. The recent demonstration that human umbilical cord blood similarly functions to rejuvenate the aged brain further advances this work to clinical translation. In this review, we focus on these blood-based rejuvenation strategies and their capacity to delay age-related molecular and functional decline in the aging brain. We discuss new findings that extend the beneficial effects of young blood to neurodegenerative disease models. Lastly, we explore the translational potential of blood-based interventions, highlighting current clinical trials aimed at addressing therapeutic applications for the treatment of dementia-related neurodegenerative disease in humans.
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Affiliation(s)
- Alana M. Horowitz
- Biomedical Sciences Graduate Program, University of California San Francisco, San Francisco, California, 94143, USA
- Department of Anatomy, University of California San Francisco, San Francisco, California, 94143, USA
| | - Saul A. Villeda
- Biomedical Sciences Graduate Program, University of California San Francisco, San Francisco, California, 94143, USA
- Department of Anatomy, University of California San Francisco, San Francisco, California, 94143, USA
- The Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California San Francisco, San Francisco, California, 94143, USA
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26
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Levine ZG, Walker S. The Biochemistry of O-GlcNAc Transferase: Which Functions Make It Essential in Mammalian Cells? Annu Rev Biochem 2017; 85:631-57. [PMID: 27294441 DOI: 10.1146/annurev-biochem-060713-035344] [Citation(s) in RCA: 128] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
O-linked N-acetylglucosamine transferase (OGT) is found in all metazoans and plays an important role in development but at the single-cell level is only essential in dividing mammalian cells. Postmitotic mammalian cells and cells of invertebrates such as Caenorhabditis elegans and Drosophila can survive without copies of OGT. Why OGT is required in dividing mammalian cells but not in other cells remains unknown. OGT has multiple biochemical activities. Beyond its well-known role in adding β-O-GlcNAc to serine and threonine residues of nuclear and cytoplasmic proteins, OGT also acts as a protease in the maturation of the cell cycle regulator host cell factor 1 (HCF-1) and serves as an integral member of several protein complexes, many of them linked to gene expression. In this review, we summarize current understanding of the mechanisms underlying OGT's biochemical activities and address whether known functions of OGT could be related to its essential role in dividing mammalian cells.
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Affiliation(s)
- Zebulon G Levine
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, Massachusetts 02115; ,
| | - Suzanne Walker
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, Massachusetts 02115; ,
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O-GlcNAcylation of SKN-1 modulates the lifespan and oxidative stress resistance in Caenorhabditis elegans. Sci Rep 2017; 7:43601. [PMID: 28272406 PMCID: PMC5341102 DOI: 10.1038/srep43601] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Accepted: 01/25/2017] [Indexed: 01/07/2023] Open
Abstract
In C. elegans, the transcription factor skinhead-1 (SKN-1), the ortholog of human NF-E2-related factor 2 (Nrf-2), plays important roles in oxidative stress defense and aging processes. It has been documented that the activity of SKN-1 is regulated by its phosphorylation modification. However, whether other posttranslational modifications of SKN-1 affect its function remains unclear to date. Here we report, for the first time, that SKN-1 is O-GlcNAcylated at Ser470 and Thr493 by O-GlcNActransferase OGT-1. By generating the double mutations of Ser470/Thr493 in the wild type and skn-1(zu67) worms, respectively, we found that disruption of O-GlcNAc modification on SKN-1 repressed the accumulation of SKN-1 in the intestinal nuclei, and decreased the activities of SKN-1 in modulating lifespan and oxidative stress resistance. Moreover, under oxidative stress, SKN-1 was highly O-GlcNAcylated, resulting in the decrease of GSK-3-mediated phosphorylation at Ser483 adjacent to the O-GlcNAcylated residues (Ser470 and Thr493). These data suggest that O-GlcNAcylation of SKN-1 is crucial for regulating lifespan and oxidative stress resistance via the crosstalk with its phosphorylation in C. elegans. These findings have important implications for studying the functions of O-GlcNAcylation on Nrf-2 in human aging-related diseases.
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28
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Kikis EA. The struggle by Caenorhabditis elegans to maintain proteostasis during aging and disease. Biol Direct 2016; 11:58. [PMID: 27809888 PMCID: PMC5093949 DOI: 10.1186/s13062-016-0161-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Accepted: 10/24/2016] [Indexed: 01/07/2023] Open
Abstract
The presence of only small amounts of misfolded protein is an indication of a healthy proteome. Maintaining proteome health, or more specifically, “proteostasis,” is the purview of the “proteostasis network.” This network must respond to constant fluctuations in the amount of destabilized proteins caused by errors in protein synthesis and exposure to acute proteotoxic conditions. Aging is associated with a gradual increase in damaged and misfolded protein, which places additional stress on the machinery of the proteostasis network. In fact, despite the ability of the proteostasis machinery to readjust its stoichiometry in an attempt to maintain homeostasis, the capacity of cells to buffer against misfolding is strikingly limited. Therefore, subtle changes in the folding environment that occur during aging can significantly impact the health of the proteome. This decline and eventual collapse in proteostasis is most pronounced in individuals with neurodegenerative disorders such as Alzheimer’s Disease, Parkinson’s Disease, and Huntington’s Disease that are caused by the misfolding, aggregation, and toxicity of certain proteins. This review discusses how C. elegans models of protein misfolding have contributed to our current understanding of the proteostasis network, its buffering capacity, and its regulation. Reviewers: This article was reviewed by Luigi Bubacco, Patrick Lewis and Xavier Roucou.
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Affiliation(s)
- Elise A Kikis
- Biology Department, The University of the South, 735 University Avenue, Sewanee, TN, 37383, USA.
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29
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Teo CF, El-Karim EG, Wells L. Dissecting PUGNAc-mediated inhibition of the pro-survival action of insulin. Glycobiology 2016; 26:1198-1208. [PMID: 27072814 PMCID: PMC5884396 DOI: 10.1093/glycob/cww043] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 04/01/2016] [Indexed: 01/02/2023] Open
Abstract
Previous studies utilizing PUGNAc, the most widely used β-N-acetylglucosaminidase (OGA) inhibitor to increase global O-N-acetylglucosamine (GlcNAc) levels, have reported a variety of effects including insulin resistance as a direct result of elevated O-GlcNAc levels. The notion of OGA inhibition causing insulin resistance was not replicated in studies in which elevated global O-GlcNAc levels were achieved using two other OGA inhibitors. Related to insulin action, work by others has suggested that O-GlcNAc elevation may inhibit the anti-apoptotic action of insulin. Thus, we examined the pro-survival action of insulin upon serum deprivation in the presence of PUGNAc as well as two selective OGA inhibitors (GlcNAcstatin-g and Thiamet-G), and a selective lysosomal hexosaminidase inhibitor (INJ2). We established that PUGNAc inhibits the pro-survival action of insulin but this effect is not recapitulated by the selective OGA inhibitors suggesting that elevation in O-GlcNAc levels alone is not responsible for PUGNAc's effect on the anti-apoptotic action of insulin. Further, we demonstrate that a selective hexosaminidase A/B (HexA/B) inhibitor does not impact insulin action suggesting that PUGNAc's effect is not due to inhibition of lysosomal hexosaminidase. Finally, we tested a combination of selective OGA and lysosomal hexosaminidase inhibitors but were not able to recapitulate the inhibition of insulin action generated by PUGNAc alone. These results strongly suggest that the defect in insulin action upon PUGNAc treatment does not derive from its inhibition of OGA or HexA/B, and that there is an unknown target of PUGNAc that is the likely culprit in inhibiting the protective effect of insulin from apoptosis.
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Affiliation(s)
- Chin Fen Teo
- Department of Biochemistry and Molecular Biology
- Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Road, Athens, GA 30602-1516, USA
| | - Enas Gad El-Karim
- Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Road, Athens, GA 30602-1516, USA
| | - Lance Wells
- Department of Biochemistry and Molecular Biology
- Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Road, Athens, GA 30602-1516, USA
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30
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Kitaoka S, Morielli AD, Zhao FQ. FGT-1-mediated glucose uptake is defective in insulin/IGF-like signaling mutants in Caenorhabditis elegans. FEBS Open Bio 2016; 6:576-85. [PMID: 27419060 PMCID: PMC4887973 DOI: 10.1002/2211-5463.12068] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Revised: 01/27/2016] [Accepted: 04/05/2016] [Indexed: 11/23/2022] Open
Abstract
Insulin signaling plays a central role in the regulation of facilitative glucose transporters (GLUTs) in humans. To establish Caenorhabditis elegans (C. elegans) as a model to study the mechanism underlying insulin regulation of GLUT, we identified that FGT‐1 is most likely the only functional GLUT homolog in C. elegans and is ubiquitously expressed. The FGT‐1‐mediated glucose uptake was almost completely defective in insulin/IGF‐like signaling (IIS) mutants daf‐2 and age‐1, and this defect mainly resulted from the down‐regulated FGT‐1 protein expression. However, glycosylation may also be involved because OGA‐1, an O‐GlcNAcase, was essential for the function of FGT‐1. Thus, our study showed that C. elegans can be a new powerful model system to study insulin regulation of GLUT.
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Affiliation(s)
- Shun Kitaoka
- Laboratory of Lactation and Metabolic Physiology Department of Animal and Veterinary Sciences University of Vermont Burlington VT USA; Present address: Drug Discovery Laboratory Wakunaga Pharmaceutical Co., Ltd. Akitakata Hiroshima Japan
| | - Anthony D Morielli
- Department of Pharmacology College of Medicine University of Vermont Burlington VT USA
| | - Feng-Qi Zhao
- Laboratory of Lactation and Metabolic Physiology Department of Animal and Veterinary Sciences University of Vermont Burlington VT USA
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31
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Hou L, Wang D, Chen D, Liu Y, Zhang Y, Cheng H, Xu C, Sun N, McDermott J, Mair WB, Han JDJ. A Systems Approach to Reverse Engineer Lifespan Extension by Dietary Restriction. Cell Metab 2016; 23:529-40. [PMID: 26959186 PMCID: PMC5110149 DOI: 10.1016/j.cmet.2016.02.002] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Revised: 12/14/2015] [Accepted: 02/03/2016] [Indexed: 12/16/2022]
Abstract
Dietary restriction (DR) is the most powerful natural means to extend lifespan. Although several genes can mediate responses to alternate DR regimens, no single genetic intervention has recapitulated the full effects of DR, and no unified system is known for different DR regimens. Here we obtain temporally resolved transcriptomes during calorie restriction and intermittent fasting in Caenorhabditis elegans and find that early and late responses involve metabolism and cell cycle/DNA damage, respectively. We uncover three network modules of DR regulators by their target specificity. By genetic manipulations of nodes representing discrete modules, we induce transcriptomes that progressively resemble DR as multiple nodes are perturbed. Targeting all three nodes simultaneously results in extremely long-lived animals that are refractory to DR. These results and dynamic simulations demonstrate that extensive feedback controls among regulators may be leveraged to drive the regulatory circuitry to a younger steady state, recapitulating the full effect of DR.
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Affiliation(s)
- Lei Hou
- Key Laboratory of Computational Biology, CAS Center for Excellence in Molecular Cell Science, Collaborative Innovation Center for Genetics and Developmental Biology, Chinese Academy of Sciences-Max Planck Partner Institute for Computational Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China
| | - Dan Wang
- Key Laboratory of Computational Biology, CAS Center for Excellence in Molecular Cell Science, Collaborative Innovation Center for Genetics and Developmental Biology, Chinese Academy of Sciences-Max Planck Partner Institute for Computational Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China; Graduate University of Chinese Academy of Sciences, Beijing 100049, China
| | - Di Chen
- State Key Laboratory of Pharmaceutical Biotechnology and MOE Key Laboratory of Model Animals for Disease Study, Model Animal Research Center, Nanjing University, Nanjing, Jiangsu 210061, China
| | - Yi Liu
- Key Laboratory of Computational Biology, CAS Center for Excellence in Molecular Cell Science, Collaborative Innovation Center for Genetics and Developmental Biology, Chinese Academy of Sciences-Max Planck Partner Institute for Computational Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China; Beijing Key Lab of Traffic Data Analysis and Mining, School of Computer and Information Technology, Beijing Jiaotong University, Beijing 100044, China
| | - Yue Zhang
- Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA
| | - Hao Cheng
- Key Laboratory of Computational Biology, CAS Center for Excellence in Molecular Cell Science, Collaborative Innovation Center for Genetics and Developmental Biology, Chinese Academy of Sciences-Max Planck Partner Institute for Computational Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China; Graduate University of Chinese Academy of Sciences, Beijing 100049, China
| | - Chi Xu
- Key Laboratory of Computational Biology, CAS Center for Excellence in Molecular Cell Science, Collaborative Innovation Center for Genetics and Developmental Biology, Chinese Academy of Sciences-Max Planck Partner Institute for Computational Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China; Graduate University of Chinese Academy of Sciences, Beijing 100049, China
| | - Na Sun
- Key Laboratory of Computational Biology, CAS Center for Excellence in Molecular Cell Science, Collaborative Innovation Center for Genetics and Developmental Biology, Chinese Academy of Sciences-Max Planck Partner Institute for Computational Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China
| | - Joseph McDermott
- Key Laboratory of Computational Biology, CAS Center for Excellence in Molecular Cell Science, Collaborative Innovation Center for Genetics and Developmental Biology, Chinese Academy of Sciences-Max Planck Partner Institute for Computational Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China
| | - William B Mair
- Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA
| | - Jing-Dong J Han
- Key Laboratory of Computational Biology, CAS Center for Excellence in Molecular Cell Science, Collaborative Innovation Center for Genetics and Developmental Biology, Chinese Academy of Sciences-Max Planck Partner Institute for Computational Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China.
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Durning SP, Flanagan-Steet H, Prasad N, Wells L. O-Linked β-N-acetylglucosamine (O-GlcNAc) Acts as a Glucose Sensor to Epigenetically Regulate the Insulin Gene in Pancreatic Beta Cells. J Biol Chem 2015; 291:2107-18. [PMID: 26598517 DOI: 10.1074/jbc.m115.693580] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Indexed: 11/06/2022] Open
Abstract
The post-translational protein modification O-linked β-N-acetylglucosamine (O-GlcNAc) is a proposed nutrient sensor that has been shown to regulate multiple biological pathways. This dynamic and inducible enzymatic modification to intracellular proteins utilizes the end product of the nutrient sensing hexosamine biosynthetic pathway, UDP-GlcNAc, as its substrate donor. Type II diabetic patients have elevated O-GlcNAc-modified proteins within pancreatic beta cells due to chronic hyperglycemia-induced glucose overload, but a molecular role for O-GlcNAc within beta cells remains unclear. Using directed pharmacological approaches in the mouse insulinoma-6 (Min6) cell line, we demonstrate that elevating nuclear O-GlcNAc increases intracellular insulin levels and preserves glucose-stimulated insulin secretion during chronic hyperglycemia. The molecular mechanism for these observed changes appears to be, at least in part, due to elevated O-GlcNAc-dependent increases in Ins1 and Ins2 mRNA levels via elevations in histone H3 transcriptional activation marks. Furthermore, RNA deep sequencing reveals that this mechanism of altered gene transcription is restricted and that the majority of genes regulated by elevated O-GlcNAc levels are similarly regulated by a shift from euglycemic to hyperglycemic conditions. These findings implicate the O-GlcNAc modification as a potential mechanism for hyperglycemic-regulated gene expression in the beta cell.
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Affiliation(s)
- Sean P Durning
- From the Complex Carbohydrate Research Center, Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602-1516 and
| | - Heather Flanagan-Steet
- From the Complex Carbohydrate Research Center, Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602-1516 and
| | - Nripesh Prasad
- HudsonAlpha Institute of Biotechnology, Genomic Services Laboratory, Huntsville, Alabama 35806
| | - Lance Wells
- From the Complex Carbohydrate Research Center, Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602-1516 and
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Senescence-Associated Changes in Proteome and O-GlcNAcylation Pattern in Human Peritoneal Mesothelial Cells. BIOMED RESEARCH INTERNATIONAL 2015; 2015:382652. [PMID: 26640786 PMCID: PMC4657062 DOI: 10.1155/2015/382652] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Revised: 10/24/2015] [Accepted: 10/25/2015] [Indexed: 12/17/2022]
Abstract
INTRODUCTION Senescence of peritoneal mesothelial cells represents a biological program defined by arrested cell growth and altered cell secretory phenotype with potential impact in peritoneal dialysis. This study aims to characterize cellular senescence at the level of global protein expression profiles and modification of proteins with O-linked N-acetylglucosamine (O-GlcNAcylation). METHODS A comparative proteomics analysis between young and senescent human peritoneal mesothelial cells (HPMC) was performed using two-dimensional gel electrophoresis. O-GlcNAc status was assessed by Western blot under normal conditions and after modulation with 6-diazo-5-oxo-L-norleucine (DON) to decrease O-GlcNAcylation or O-(2-acetamido-2-deoxy-D-glucopyranosylidene) amino N-phenyl carbamate (PUGNAc) to increase O-GlcNAcylation. RESULTS Comparison of protein pattern of senescent and young HPMC revealed 29 differentially abundant protein spots, 11 of which were identified to be actin (cytoplasmic 1 and 2), cytokeratin-7, cofilin-2, transgelin-2, Hsp60, Hsc70, proteasome β-subunits (type-2 and type-3), nucleoside diphosphate kinase A, and cytosolic 5'(3')-deoxyribonucleotidase. Although the global level of O-GlcNAcylation was comparable, senescent cells were not sensitive to modulation by PUGNAc. DISCUSSION This study identified changes of the proteome and altered dynamics of O-GlcNAc regulation in senescent mesothelial cells. Whereas changes in cytoskeleton-associated proteins likely reflect altered cell morphology, changes in chaperoning and housekeeping proteins may have functional impact on cellular stress response in peritoneal dialysis.
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35
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Epigenetic regulation of ageing: linking environmental inputs to genomic stability. Nat Rev Mol Cell Biol 2015; 16:593-610. [PMID: 26373265 DOI: 10.1038/nrm4048] [Citation(s) in RCA: 389] [Impact Index Per Article: 43.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Ageing is affected by both genetic and non-genetic factors. Here, we review the chromatin-based epigenetic changes that occur during ageing, the role of chromatin modifiers in modulating lifespan and the importance of epigenetic signatures as biomarkers of ageing. We also discuss how epigenome remodelling by environmental stimuli affects several aspects of transcription and genomic stability, with important consequences for longevity, and outline epigenetic differences between the 'mortal soma' and the 'immortal germ line'. Finally, we discuss the inheritance of characteristics of ageing and potential chromatin-based strategies to delay or reverse hallmarks of ageing or age-related diseases.
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Zhong J, Martinez M, Sengupta S, Lee A, Wu X, Chaerkady R, Chatterjee A, O'Meally RN, Cole RN, Pandey A, Zachara NE. Quantitative phosphoproteomics reveals crosstalk between phosphorylation and O-GlcNAc in the DNA damage response pathway. Proteomics 2015; 15:591-607. [PMID: 25263469 DOI: 10.1002/pmic.201400339] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2014] [Revised: 09/02/2014] [Accepted: 09/24/2014] [Indexed: 11/07/2022]
Abstract
The modification of intracellular proteins by monosaccharides of O-linked β-N-acetylglucosamine (O-GlcNAc) is an essential and dynamic PTM of metazoans. The addition and removal of O-GlcNAc is catalyzed by the O-GlcNAc transferase (OGT) and O-GlcNAcase, respectively. One mechanism by which O-GlcNAc is thought to mediate proteins is by regulating phosphorylation. To provide insight into the pathways regulated by O-GlcNAc, we have utilized SILAC-based quantitative proteomics to carry out comparisons of site-specific phosphorylation in OGT wild-type and Null cells. Quantitation of the phosphoproteome demonstrated that of 5529 phosphoserine, phosphothreonine, and phosphotyrosine sites, 232 phosphosites were upregulated and 133 downregulated in the absence of O-GlcNAc. Collectively, these data suggest that deletion of OGT has a profound effect on the phosphorylation of cell cycle and DNA damage response proteins. Key events were confirmed by biochemical analyses and demonstrate an increase in the activating autophosphorylation event on ATM (Ser1987) and on ATM's downstream targets p53, H2AX, and Chk2. Together, these data support widespread changes in the phosphoproteome upon removal of O-GlcNAc, suggesting that O-GlcNAc regulates processes such as the cell cycle, genomic stability, and lysosomal biogenesis. All MS data have been deposited in the ProteomeXchange with identifier PXD001153 (http://proteomecentral.proteomexchange.org/dataset/PXD001153).
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Affiliation(s)
- Jun Zhong
- McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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37
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Zhu Y, Liu TW, Madden Z, Yuzwa SA, Murray K, Cecioni S, Zachara N, Vocadlo DJ. Post-translational O-GlcNAcylation is essential for nuclear pore integrity and maintenance of the pore selectivity filter. J Mol Cell Biol 2015; 8:2-16. [PMID: 26031751 DOI: 10.1093/jmcb/mjv033] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2015] [Accepted: 04/13/2015] [Indexed: 01/12/2023] Open
Abstract
O-glycosylation of the nuclear pore complex (NPC) by O-linked N-acetylglucosamine (O-GlcNAc) is conserved within metazoans. Many nucleoporins (Nups) comprising the NPC are constitutively O-GlcNAcylated, but the functional role of this modification remains enigmatic. We show that loss of O-GlcNAc, induced by either inhibition of O-GlcNAc transferase (OGT) or deletion of the gene encoding OGT, leads to decreased cellular levels of a number of natively O-GlcNAcylated Nups. Loss of O-GlcNAc enables increased ubiquitination of these Nups and their increased proteasomal degradation. The decreased half-life of these deglycosylated Nups manifests in their gradual loss from the NPC and a downstream malfunction of the nuclear pore selective permeability barrier in both dividing and post-mitotic cells. These findings define a critical role of O-GlcNAc modification of the NPC in maintaining its composition and the function of the selectivity filter. The results implicate NPC glycosylation as a regulator of NPC function and reveal the role of conserved glycosylation of the NPC among metazoans.
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Affiliation(s)
- Yanping Zhu
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| | - Ta-Wei Liu
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| | - Zarina Madden
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| | - Scott A Yuzwa
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| | - Kelsey Murray
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| | - Samy Cecioni
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
| | - Natasha Zachara
- Department of Biological Chemistry, Johns Hopkins University Medical School, Baltimore, MD 21205, USA
| | - David J Vocadlo
- Department of Chemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada
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38
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Selvan N, Mariappa D, van den Toorn HWP, Heck AJR, Ferenbach AT, van Aalten DMF. The Early Metazoan Trichoplax adhaerens Possesses a Functional O-GlcNAc System. J Biol Chem 2015; 290:11969-82. [PMID: 25778404 PMCID: PMC4424335 DOI: 10.1074/jbc.m114.628750] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Indexed: 01/09/2023] Open
Abstract
Protein O-GlcNAcylation is a reversible post-translational signaling modification of nucleocytoplasmic proteins that is essential for embryonic development in bilateria. In a search for a reductionist model to study O-GlcNAc signaling, we discovered the presence of functional O-GlcNAc transferase (OGT), O-GlcNAcase (OGA), and nucleocytoplasmic protein O-GlcNAcylation in the most basal extant animal, the placozoan Trichoplax adhaerens. We show via enzymatic characterization of Trichoplax OGT/OGA and genetic rescue experiments in Drosophila melanogaster that these proteins possess activities/functions similar to their bilaterian counterparts. The acquisition of O-GlcNAc signaling by metazoa may have facilitated the rapid and complex signaling mechanisms required for the evolution of multicellular organisms.
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Affiliation(s)
| | - Daniel Mariappa
- MRC Protein Phosphorylation and Ubiquitylation Unit, College of Life Sciences, University of Dundee, Dow Street, Dundee, DD1 5EH, United Kingdom and
| | - Henk W P van den Toorn
- the Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - Albert J R Heck
- the Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
| | | | - Daan M F van Aalten
- From the Division of Molecular Microbiology and MRC Protein Phosphorylation and Ubiquitylation Unit, College of Life Sciences, University of Dundee, Dow Street, Dundee, DD1 5EH, United Kingdom and
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39
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Keembiyehetty C, Love DC, Harwood KR, Gavrilova O, Comly ME, Hanover JA. Conditional knock-out reveals a requirement for O-linked N-Acetylglucosaminase (O-GlcNAcase) in metabolic homeostasis. J Biol Chem 2015; 290:7097-113. [PMID: 25596529 DOI: 10.1074/jbc.m114.617779] [Citation(s) in RCA: 105] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
O-GlcNAc cycling is maintained by the reciprocal activities of the O-GlcNAc transferase and the O-GlcNAcase (OGA) enzymes. O-GlcNAc transferase is responsible for O-GlcNAc addition to serine and threonine (Ser/Thr) residues and OGA for its removal. Although the Oga gene (MGEA5) is a documented human diabetes susceptibility locus, its role in maintaining insulin-glucose homeostasis is unclear. Here, we report a conditional disruption of the Oga gene in the mouse. The resulting homozygous Oga null (KO) animals lack OGA enzymatic activity and exhibit elevated levels of the O-GlcNAc modification. The Oga KO animals showed nearly complete perinatal lethality associated with low circulating glucose and low liver glycogen stores. Defective insulin-responsive GSK3β phosphorylation was observed in both heterozygous (HET) and KO Oga animals. Although Oga HET animals were viable, they exhibited alterations in both transcription and metabolism. Transcriptome analysis using mouse embryonic fibroblasts revealed deregulation in the transcripts of both HET and KO animals specifically in genes associated with metabolism and growth. Additionally, metabolic profiling showed increased fat accumulation in HET and KO animals compared with WT, which was increased by a high fat diet. Reduced insulin sensitivity, glucose tolerance, and hyperleptinemia were also observed in HET and KO female mice. Notably, the respiratory exchange ratio of the HET animals was higher than that observed in WT animals, indicating the preferential utilization of glucose as an energy source. These results suggest that the loss of mouse OGA leads to defects in metabolic homeostasis culminating in obesity and insulin resistance.
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Affiliation(s)
| | - Dona C Love
- From the Laboratory of Cell Biology and Biochemistry and
| | | | - Oksana Gavrilova
- Mouse Metabolic Core Laboratory, NIDDK, National Institutes of Health, Bethesda, Maryland 20892
| | | | - John A Hanover
- From the Laboratory of Cell Biology and Biochemistry and
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40
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Bond MR, Ghosh SK, Wang P, Hanover JA. Conserved nutrient sensor O-GlcNAc transferase is integral to C. elegans pathogen-specific immunity. PLoS One 2014; 9:e113231. [PMID: 25474640 PMCID: PMC4256294 DOI: 10.1371/journal.pone.0113231] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2014] [Accepted: 10/21/2014] [Indexed: 11/19/2022] Open
Abstract
Discriminating pathogenic bacteria from bacteria used as a food source is key to Caenorhabidits elegans immunity. Using mutants defective in the enzymes of O-linked N-acetylglucosamine (O-GlcNAc) cycling, we examined the role of this nutrient-sensing pathway in the C. elegans innate immune response. Genetic analysis showed that deletion of O-GlcNAc transferase (ogt-1) yielded animals hypersensitive to the human pathogen S. aureus but not to P. aeruginosa. Genetic interaction studies revealed that nutrient-responsive OGT-1 acts through the conserved β-catenin (BAR-1) pathway and in concert with p38 MAPK (PMK-1) to modulate the immune response to S. aureus. Moreover, whole genome transcriptional profiling revealed that O-GlcNAc cycling mutants exhibited deregulation of unique stress- and immune-responsive genes. The participation of nutrient sensor OGT-1 in an immunity module evolutionarily conserved from C. elegans to humans reveals an unexplored nexus between nutrient availability and a pathogen-specific immune response.
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Affiliation(s)
- Michelle R. Bond
- National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Salil K. Ghosh
- Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland, United States of America
| | - Peng Wang
- Department of Pathology, Medstar Georgetown University Hospital, Washington, District of Columbia, United States of America
| | - John A. Hanover
- National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
- * E-mail:
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41
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Hexosamine pathway and (ER) protein quality control. Curr Opin Cell Biol 2014; 33:14-8. [PMID: 25463841 DOI: 10.1016/j.ceb.2014.10.001] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Revised: 10/02/2014] [Accepted: 10/06/2014] [Indexed: 11/21/2022]
Abstract
Aminosugars produced in the hexosamine pathway (HP) are utilized in protein glycosylation reactions involved in protein maturation and cellular signaling. Recent evidence revealed a role of the HP in protein quality control and ageing. Elevation of the HP product UDP-N-acetylglucosamine in the nematode Caenorhabditis elegans results in resistance towards toxic aggregation-prone proteins, and extended lifespan. Glutamine-fructose 6 phosphate aminotransferase (GFAT-1), the HP's key enzyme, is a target of the unfolded protein response (UPR). Thus, cardiac stress in mice results in GFAT-1 activation that triggers a cytoprotective response. Feeding of glucosamine to aged mice increases their life expectancy. Here we discuss HP activation and cellular protein quality control mechanisms that result in stress resistance and suppression of age-related proteotoxicity.
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42
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Vaidyanathan K, Wells L. Multiple tissue-specific roles for the O-GlcNAc post-translational modification in the induction of and complications arising from type II diabetes. J Biol Chem 2014; 289:34466-71. [PMID: 25336652 DOI: 10.1074/jbc.r114.591560] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
In this minireview, we will highlight work in the last 30 years that has clearly demonstrated that the O-GlcNAc modification is nutrient-responsive and plays multiple roles in metabolic regulation of signaling and gene expression. Further, we will examine recent studies that have investigated the impact of O-GlcNAc in a variety of glucose- and insulin-responsive tissues and the roles attributed to O-GlcNAc in the induction of insulin resistance and glucose toxicity, the hallmarks of type II diabetes mellitus. We will also summarize potential causal roles for the O-GlcNAc modification in complications associated with diabetes.
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Affiliation(s)
- Krithika Vaidyanathan
- From the Department of Biochemistry and Molecular Biology and Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia 30602-1516
| | - Lance Wells
- From the Department of Biochemistry and Molecular Biology and Complex Carbohydrate Research Center, University of Georgia, Athens, Georgia 30602-1516
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43
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Alonso J, Schimpl M, van Aalten DMF. O-GlcNAcase: promiscuous hexosaminidase or key regulator of O-GlcNAc signaling? J Biol Chem 2014; 289:34433-9. [PMID: 25336650 PMCID: PMC4263850 DOI: 10.1074/jbc.r114.609198] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
O-GlcNAc signaling is regulated by an opposing pair of enzymes: O-GlcNAc transferase installs and O-GlcNAcase (OGA) removes the modification from proteins. The dynamics and regulation of this process are only beginning to be understood as the physiological functions of both enzymes are being probed using genetic and pharmacological approaches. This minireview charts the discovery and functional and structural analysis of OGA and summarizes the insights gained from recent studies using OGA inhibition, gene knock-out, and overexpression. We identify several areas of “known unknowns” that would benefit from future research, such as the enigmatic C-terminal domain of OGA.
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Affiliation(s)
- Jana Alonso
- From the Medical Research Council Protein Phosphorylation and Ubiquitylation Unit and
| | - Marianne Schimpl
- From the Medical Research Council Protein Phosphorylation and Ubiquitylation Unit and
| | - Daan M F van Aalten
- From the Medical Research Council Protein Phosphorylation and Ubiquitylation Unit and Division of Molecular Microbiology, College of Life Sciences, University of Dundee, DD1 5EH Dundee, Scotland, United Kingdom
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44
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Gatsi R, Schulze B, Rodríguez-Palero MJ, Hernando-Rodríguez B, Baumeister R, Artal-Sanz M. Prohibitin-mediated lifespan and mitochondrial stress implicate SGK-1, insulin/IGF and mTORC2 in C. elegans. PLoS One 2014; 9:e107671. [PMID: 25265021 PMCID: PMC4180437 DOI: 10.1371/journal.pone.0107671] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2014] [Accepted: 08/13/2014] [Indexed: 12/29/2022] Open
Abstract
Lifespan regulation by mitochondrial proteins has been well described, however, the mechanism of this regulation is not fully understood. Amongst the mitochondrial proteins profoundly affecting ageing are prohibitins (PHB-1 and PHB-2). Paradoxically, in C. elegans prohibitin depletion shortens the lifespan of wild type animals while dramatically extending that of metabolically compromised animals, such as daf-2-insulin-receptor mutants. Here we show that amongst the three kinases known to act downstream of daf-2, only loss of function of sgk-1 recapitulates the ageing phenotype observed in daf-2 mutants upon prohibitin depletion. Interestingly, signalling through SGK-1 receives input from an additional pathway, parallel to DAF-2, for the prohibitin-mediated lifespan phenotype. We investigated the effect of prohibitin depletion on the mitochondrial unfolded protein response (UPRmt). Remarkably, the lifespan extension upon prohibitin elimination, of both daf-2 and sgk-1 mutants, is accompanied by suppression of the UPRmt induced by lack of prohibitin. On the contrary, gain of function of SGK-1 results in further shortening of lifespan and a further increase of the UPRmt in prohibitin depleted animals. Moreover, SGK-1 interacts with RICT-1 for the regulation of the UPRmt in a parallel pathway to DAF-2. Interestingly, prohibitin depletion in rict-1 loss of function mutant animals also causes lifespan extension. Finally, we reveal an unprecedented role for mTORC2-SGK-1 in the regulation of mitochodrial homeostasis. Together, these results give further insight into the mechanism of lifespan regulation by mitochondrial function and reveal a cross-talk of mitochondria with two key pathways, Insulin/IGF and mTORC2, for the regulation of ageing and stress response.
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Affiliation(s)
- Roxani Gatsi
- CABD, Centro Andaluz de Biología del Desarrollo, CSIC-Universidad Pablo de Olavide-Junta de Andalucía, Sevilla, Spain
| | - Bettina Schulze
- Centre for Biological Signalling Studies (BIOSS), Albert-Ludwigs-University of Freiburg, Freiburg, Germany
- Laboratory for Bioinformatics and Molecular Genetics, Faculty of Biology, Albert-Ludwigs-University of Freiburg, Freiburg, Germany
| | - María Jesús Rodríguez-Palero
- CABD, Centro Andaluz de Biología del Desarrollo, CSIC-Universidad Pablo de Olavide-Junta de Andalucía, Sevilla, Spain
| | - Blanca Hernando-Rodríguez
- CABD, Centro Andaluz de Biología del Desarrollo, CSIC-Universidad Pablo de Olavide-Junta de Andalucía, Sevilla, Spain
| | - Ralf Baumeister
- Centre for Biological Signalling Studies (BIOSS), Albert-Ludwigs-University of Freiburg, Freiburg, Germany
- Laboratory for Bioinformatics and Molecular Genetics, Faculty of Biology, Albert-Ludwigs-University of Freiburg, Freiburg, Germany
- Center for Biochemistry and Molecular Cell Research, Faculty of Medicine, Albert-Ludwigs-University of Freiburg, Freiburg, Germany
| | - Marta Artal-Sanz
- CABD, Centro Andaluz de Biología del Desarrollo, CSIC-Universidad Pablo de Olavide-Junta de Andalucía, Sevilla, Spain
- Centre for Biological Signalling Studies (BIOSS), Albert-Ludwigs-University of Freiburg, Freiburg, Germany
- Laboratory for Bioinformatics and Molecular Genetics, Faculty of Biology, Albert-Ludwigs-University of Freiburg, Freiburg, Germany
- * E-mail:
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45
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Leontieva OV, Demidenko ZN, Blagosklonny MV. Rapamycin reverses insulin resistance (IR) in high-glucose medium without causing IR in normoglycemic medium. Cell Death Dis 2014; 5:e1214. [PMID: 24810050 PMCID: PMC4047870 DOI: 10.1038/cddis.2014.178] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2014] [Revised: 03/17/2014] [Accepted: 03/26/2014] [Indexed: 02/08/2023]
Abstract
Mammalian target of rapamycin (mTOR) is involved in insulin resistance (IR) and diabetic retinopathy. In retinal pigment epithelial (RPE) cells, insulin activates the mTOR pathway, inducing hypoxia-inducible factor-1α (HIF-1α) and HIF-dependent transcription in serum-free minimum essential medium Eagle (MEM). Serendipitously, we found that insulin failed to induce the HIF-1α-dependent response, when RPE cells were cultured in Dulbecco's modification of Eagle's medium (DMEM). Whereas concentration of glucose in MEM corresponds to normal glucose levels in blood (5.5 mM), its concentration in DMEM corresponds to severe diabetic hyperglycemia (25 mM). Addition of glucose to MEM also caused IR. Glucose-mediated IR was characterized by basal activation of mTORC1 and its poor inducibility by insulin. Basal levels of phosphorylated S6 kinase (S6K), S6 and insulin receptor substrate 1 (IRS1) S635/639 were high, whereas their inducibilities were decreased. Insulin-induced Akt phosphorylation was decreased and restored by rapamycin and an inhibitor of S6K. IR was associated with de-phosphorylation of IRS1 at S1011, which was reversed by rapamycin. Both short (16–40 h) and chronic (2 weeks) treatment with rapamycin reversed IR. Furthermore, rapamycin did not impair Akt activation in RPE cells cultured in normoglycemic media. In contrast, Torin 1 blocked Akt activation by insulin. We conclude that by activating mTOR/S6K glucose causes feedback IR, preventable by rapamycin. Rapamycin does not cause IR in RPE cells regardless of the duration of treatment. We confirmed that rapamycin also did not impair phosphorylation of Akt at T308 and S473 in normal myoblast C2C12 cells. Our work provides insights in glucose-induced IR and suggests therapeutic approaches to treat patients with IR and severe hyperglycemia and to prevent diabetic complications such as retinopathy. Also our results prompt to reconsider physiological relevance of numerous data and paradigms on IR given that most cell lines are cultured with grossly super-physiological levels of glucose.
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Affiliation(s)
- O V Leontieva
- Department of Cell Stress Biology, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, NY, USA
| | - Z N Demidenko
- Department of Cell Stress Biology, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, NY, USA
| | - M V Blagosklonny
- Department of Cell Stress Biology, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, NY, USA
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46
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O-GlcNAc reports ambient temperature and confers heat resistance on ectotherm development. Proc Natl Acad Sci U S A 2014; 111:5592-7. [PMID: 24706800 DOI: 10.1073/pnas.1322396111] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Effects of temperature on biological processes are complex. Diffusion is less affected than the diverse enzymatic reactions that have distinct individual temperature profiles. Hence thermal fluctuations pose a formidable challenge to ectothermic organisms in which body temperature is largely dictated by the ambient temperature. How cells in ectotherms cope with the myriad disruptive effects of temperature variation is poorly understood at the molecular level. Here we show that nucleocytoplasmic posttranslational modification of proteins with O-linked GlcNAc (O-GlcNAc) is closely correlated with ambient temperature during development of distantly related ectotherms ranging from the insect Drosophila melanogaster to the nematode Caenorhabditis elegans to the fish Danio rerio. Regulation seems to occur at the level of activity of the only two enzymes, O-GlcNAc transferase and O-GlcNAcase, that add and remove, respectively, this posttranslational modification in nucleus and cytoplasm. With genetic approaches in D. melanogaster and C. elegans, we demonstrate the importance of high levels of this posttranslational modification for successful development at elevated temperatures. Because many cytoplasmic and nuclear proteins in diverse pathways are O-GlcNAc targets, temperature-dependent regulation of this modification might contribute to an efficient coordinate adjustment of cellular processes in response to thermal change.
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47
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Abstract
Recent discoveries suggest that aging is neither driven by accumulation of molecular damage of any cause, nor by random damage of any kind. Some predictions of a new theory, quasi-programmed hyperfunction, have already been confirmed and a clinically-available drug slows aging and delays diseases in animals. The relationship between diseases and aging becomes easily apparent. Yet, the essence of aging turns out to be so startling that the theory cannot be instantly accepted and any possible arguments are raised for its disposal. I discuss that these arguments actually support a new theory. Are any questions remaining? And might accumulation of molecular damage still play a peculiar role in aging?
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Affiliation(s)
- Mikhail V Blagosklonny
- Department of Cell Stress Biology, Roswell Park Cancer Institute, BLSC, L3-312, Elm and Carlton Streets, Buffalo, NY 14263, USA.
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48
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JebaMercy G, Vigneshwari L, Balamurugan K. A MAP Kinase pathway in Caenorhabditis elegans is required for defense against infection by opportunistic Proteus species. Microbes Infect 2013; 15:550-68. [DOI: 10.1016/j.micinf.2013.03.009] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2012] [Revised: 03/28/2013] [Accepted: 03/28/2013] [Indexed: 12/16/2022]
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49
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McCormick MA, Kennedy BK. Genome-scale studies of aging: challenges and opportunities. Curr Genomics 2013; 13:500-7. [PMID: 23633910 PMCID: PMC3468883 DOI: 10.2174/138920212803251454] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2012] [Revised: 06/08/2012] [Accepted: 07/25/2012] [Indexed: 12/21/2022] Open
Abstract
Whole-genome studies involving a phenotype of interest are increasingly prevalent, in part due to a dramatic increase in speed at which many high throughput technologies can be performed coupled to simultaneous decreases in cost. This type of genome-scale methodology has been applied to the phenotype of lifespan, as well as to whole-transcriptome changes during the aging process or in mutants affecting aging. The value of high throughput discovery-based science in this field is clearly evident, but will it yield a true systems-level understanding of the aging process? Here we review some of this work to date, focusing on recent findings and the unanswered puzzles to which they point. In this context, we also discuss recent technological advances and some of the likely future directions that they portend.
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50
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JebaMercy G, Balamurugan K. Effects of sequential infections of Caenorhabditis elegans with Staphylococcus aureus and Proteus mirabilis. Microbiol Immunol 2013; 56:825-35. [PMID: 22957781 DOI: 10.1111/j.1348-0421.2012.00509.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Caenorhabditis elegans can be used to study the dynamics of polymicrobial infections, specifically those between Gram-positive and Gram-negative bacteria. With C. elegans, Proteus mirabilis acts as an opportunistic pathogen and does not kill this host. Hence, in the present study, C. elegans was immunochallenged by pre-infecting it with the pathogen Staphylococcus aureus in order to study the subsequent effect of P. mirabilis on the host. It was found that 12 hrs of S. aureus and 80 hrs of subsequent P. mirabilis infection significantly reduced the life span of exposed C. elegans by 80%. However, preinfection with S. aureus for 8 and 4 hrs reduced the life span of C. elegans by only 60 and 30%, respectively. Further, there was greater production of reactive oxygen species in the sequentially infected samples than in the S. aureus and P. mirabilis controls. Real time PCR analysis indicated regulation of candidate immune regulatory genes, lysozyme (lys-7), CUB-like proteins (F08G5.6), neuropeptide-like factors (nlp-29), transcription factors of mitogen-activated protein kinase (ATF-7) and daf-2-daf-16 (daf-16), insulin-like signaling pathways and C-type lectin (clec-60 and clec-87) family members during S. aureus and subsequent P. mirabilis-mediated infections, indicating possible roles of, and contributions by, the above factors during host immune responses against these sequential infections. The present findings demonstrate that S. aureus infections increase the vulnerability of the C. elegans host by subverting its immune system, which then permits the opportunistic pathogen P. mirabilis to be pathogenic to this host.
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