1
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Su F, Koeberle A. Regulation and targeting of SREBP-1 in hepatocellular carcinoma. Cancer Metastasis Rev 2024; 43:673-708. [PMID: 38036934 PMCID: PMC11156753 DOI: 10.1007/s10555-023-10156-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Accepted: 11/10/2023] [Indexed: 12/02/2023]
Abstract
Hepatocellular carcinoma (HCC) is an increasing burden on global public health and is associated with enhanced lipogenesis, fatty acid uptake, and lipid metabolic reprogramming. De novo lipogenesis is under the control of the transcription factor sterol regulatory element-binding protein 1 (SREBP-1) and essentially contributes to HCC progression. Here, we summarize the current knowledge on the regulation of SREBP-1 isoforms in HCC based on cellular, animal, and clinical data. Specifically, we (i) address the overarching mechanisms for regulating SREBP-1 transcription, proteolytic processing, nuclear stability, and transactivation and (ii) critically discuss their impact on HCC, taking into account (iii) insights from pharmacological approaches. Emphasis is placed on cross-talk with the phosphatidylinositol-3-kinase (PI3K)-protein kinase B (Akt)-mechanistic target of rapamycin (mTOR) axis, AMP-activated protein kinase (AMPK), protein kinase A (PKA), and other kinases that directly phosphorylate SREBP-1; transcription factors, such as liver X receptor (LXR), peroxisome proliferator-activated receptors (PPARs), proliferator-activated receptor γ co-activator 1 (PGC-1), signal transducers and activators of transcription (STATs), and Myc; epigenetic mechanisms; post-translational modifications of SREBP-1; and SREBP-1-regulatory metabolites such as oxysterols and polyunsaturated fatty acids. By carefully scrutinizing the role of SREBP-1 in HCC development, progression, metastasis, and therapy resistance, we shed light on the potential of SREBP-1-targeting strategies in HCC prevention and treatment.
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Affiliation(s)
- Fengting Su
- Michael Popp Institute and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, 6020, Innsbruck, Austria
| | - Andreas Koeberle
- Michael Popp Institute and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, 6020, Innsbruck, Austria.
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2
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Jiang W, Jin WL, Xu AM. Cholesterol metabolism in tumor microenvironment: cancer hallmarks and therapeutic opportunities. Int J Biol Sci 2024; 20:2044-2071. [PMID: 38617549 PMCID: PMC11008265 DOI: 10.7150/ijbs.92274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Accepted: 02/27/2024] [Indexed: 04/16/2024] Open
Abstract
Cholesterol is crucial for cell survival and growth, and dysregulation of cholesterol homeostasis has been linked to the development of cancer. The tumor microenvironment (TME) facilitates tumor cell survival and growth, and crosstalk between cholesterol metabolism and the TME contributes to tumorigenesis and tumor progression. Targeting cholesterol metabolism has demonstrated significant antitumor effects in preclinical and clinical studies. In this review, we discuss the regulatory mechanisms of cholesterol homeostasis and the impact of its dysregulation on the hallmarks of cancer. We also describe how cholesterol metabolism reprograms the TME across seven specialized microenvironments. Furthermore, we discuss the potential of targeting cholesterol metabolism as a therapeutic strategy for tumors. This approach not only exerts antitumor effects in monotherapy and combination therapy but also mitigates the adverse effects associated with conventional tumor therapy. Finally, we outline the unresolved questions and suggest potential avenues for future investigations on cholesterol metabolism in relation to cancer.
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Affiliation(s)
- Wen Jiang
- Department of General Surgery, The First Affiliated Hospital of Anhui Medical University, Hefei 230022, P. R. China
| | - Wei-Lin Jin
- Institute of Cancer Neuroscience, Medical Frontier Innovation Research Center, The First Hospital of Lanzhou University, Lanzhou 730000, P. R. China
| | - A-Man Xu
- Department of General Surgery, The First Affiliated Hospital of Anhui Medical University, Hefei 230022, P. R. China
- Anhui Public Health Clinical Center, Hefei 230022, P. R. China
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3
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Meng C, Zhou L, Huang L, Gu Q, Du X, Wang C, Liu F, Xia C. Chlorogenic acid regulates the expression of NPC1L1 and HMGCR through PXR and SREBP2 signaling pathways and their interactions with HSP90 to maintain cholesterol homeostasis. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2024; 123:155271. [PMID: 38103317 DOI: 10.1016/j.phymed.2023.155271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 11/28/2023] [Accepted: 12/07/2023] [Indexed: 12/19/2023]
Abstract
BACKGROUND Hypercholesterolemia is widely implicated in the etiology of coronary heart disease, stroke, and dementia. Evidence suggests that chlorogenic acid (CA) reduces the risk of cardiovascular disease. PURPOSE The current study aims to explore the underlying molecular mechanism of CA in lowering cholesterol based on pregnane X receptor (PXR) and sterol regulatory element-binding protein 2 (SREBP2) regulatory pathways and their interactions with heat shock protein 90 (HSP90). METHODS A hypercholesterolemic mouse model, HepG2 and Caco2 cell models, metabolomics analysis, and co-immunoprecipitation (COIP) were used to study the mechanism of CA lowering cholesterol. RESULTS Treatment of the hypercholesterolemic mice with CA for 12 weeks significantly reduced body weight, blood lipid, hepatic lipid accumulation, and increased lipid excretion. The nuclear aggregation of PXR and SREBP2 was inhibited simultaneously. In addition, the expression of downstream target genes, including Niemann-pick C1-like 1 (NPC1L1) and 3‑hydroxy-3-methylglutaryl-CoA reductase (HMGCR), was downregulated after CA administration. Furthermore, in HepG2 and Caco2 cell models, CA reduced intracellular cholesterol levels by inhibiting the nuclear translocation of PXR and SREBP2 and the expression of NPC1L1 and HMGCR. SREBP2 interacts with PXR through HSP90, and CA reduces the binding stability of SREBP2 and HSP90 and enhances the binding of PXR and HSP90, thus reducing the nuclear accumulation of SREBP2 and PXR simultaneously. Moreover, CA promoted the phosphorylation of AMP-activated protein kinase (AMPK) and its binding to SREBP2. This was not conducive to the binding of HSP90 and SREBP2 but enhanced the binding of HSP90 and PXR, thereby inhibiting the nuclear translocation of SREBP2 and PXR and reducing intracellular cholesterol levels. However, no noticeable direct binding between AMPK and PXR was observed. CONCLUSION CA downregulates NPC1L1 and HMGCR expression by acting on the AMPK/SREBP2 direct pathway and the AMPK/SREBP2/HSP90/PXR indirect pathway, thus retaining cholesterol homeostasis.
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Affiliation(s)
- Chao Meng
- Clinical Pharmacology Institute, Pharmaceutical School, Nanchang University, Xuefu road 1299, Nanchang 330031, PR China
| | - Lingye Zhou
- Clinical Pharmacology Institute, Pharmaceutical School, Nanchang University, Xuefu road 1299, Nanchang 330031, PR China
| | - Lin Huang
- Clinical Pharmacology Institute, Pharmaceutical School, Nanchang University, Xuefu road 1299, Nanchang 330031, PR China
| | - Qi Gu
- Clinical Pharmacology Institute, Pharmaceutical School, Nanchang University, Xuefu road 1299, Nanchang 330031, PR China
| | - Xinyue Du
- Clinical Pharmacology Institute, Pharmaceutical School, Nanchang University, Xuefu road 1299, Nanchang 330031, PR China
| | - Cheng Wang
- Clinical Pharmacology Institute, Pharmaceutical School, Nanchang University, Xuefu road 1299, Nanchang 330031, PR China; Jiangxi Key Laboratory of Clinical Pharmacokinetics, Nanchang 330031, PR China
| | - Fanglan Liu
- Clinical Pharmacology Institute, Pharmaceutical School, Nanchang University, Xuefu road 1299, Nanchang 330031, PR China; Jiangxi Key Laboratory of Clinical Pharmacokinetics, Nanchang 330031, PR China
| | - Chunhua Xia
- Clinical Pharmacology Institute, Pharmaceutical School, Nanchang University, Xuefu road 1299, Nanchang 330031, PR China; Jiangxi Key Laboratory of Clinical Pharmacokinetics, Nanchang 330031, PR China.
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4
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Hu C, Wu H, Zhu Q, Cao N, Wang H. Cholesterol metabolism in T-cell aging: Accomplices or victims. FASEB J 2023; 37:e23136. [PMID: 37584624 DOI: 10.1096/fj.202300515r] [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: 03/18/2023] [Revised: 07/12/2023] [Accepted: 07/31/2023] [Indexed: 08/17/2023]
Abstract
Aging has a significant impact on the function and metabolism of T cells. Cholesterol, the most important sterol in mammals, is known as the "gold of the body" because it maintains membrane fluidity, rigidity, and signal transduction while also serving as a precursor of oxysterols, bile acids, and steroid hormones. Cholesterol homeostasis is primarily controlled by uptake, biosynthesis, efflux, and regulatory mechanisms. Previous studies have suggested that there are reciprocal interactions between cholesterol metabolism and T lymphocytes. Here, we will summarize the most recent advances in the effects of cholesterol and its derivatives on T-cell aging. We will furthermore discuss interventions that might be used to help older individuals with immune deficiencies or diminishing immune competence.
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Affiliation(s)
- Cexun Hu
- Department of Clinical Genetics, Yueyang Maternal and Child Health-Care Hospital, Yueyang, P.R. China
- Department of Immunology, Key Laboratory of Medical Science and Laboratory Medicine of Jiangsu Province, School of Medicine, Jiangsu University, Zhenjiang, P.R. China
| | - Hongliang Wu
- Department of Clinical Genetics, Yueyang Maternal and Child Health-Care Hospital, Yueyang, P.R. China
| | - Qun Zhu
- Department of Clinical Genetics, Yueyang Maternal and Child Health-Care Hospital, Yueyang, P.R. China
| | - Na Cao
- Department of Hematology, Yueyang People's Hospital, Yueyang, P. R. China
- Yueyang Hospital Affiliated to Hunan Normal University, Yueyang, P.R. China
| | - Hui Wang
- Department of Immunology, Key Laboratory of Medical Science and Laboratory Medicine of Jiangsu Province, School of Medicine, Jiangsu University, Zhenjiang, P.R. China
- Department of Immunology, School of Medicine, Jiangsu University, Zhenjiang, P.R. China
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5
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Bao C, Wu T, Zhu S, Wang X, Zhang Y, Wang X, Yang L, He C. Regulation of cholesterol homeostasis in osteoporosis mechanisms and therapeutics. Clin Sci (Lond) 2023; 137:1131-1143. [PMID: 37553962 DOI: 10.1042/cs20220752] [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: 11/04/2022] [Revised: 06/27/2023] [Accepted: 07/03/2023] [Indexed: 08/10/2023]
Abstract
Osteoporosis is a metabolic bone disease that affects hundreds of millions of people worldwide and is characterized by excessive loss of bone protein and mineral content. The incidence and mortality of osteoporosis increase with age, creating a significant medical and economic burden globally. The importance of cholesterol levels has been reported in the development of diseases including osteoporosis. It is important to note that key enzymes and molecules involved in cholesterol homeostasis are closely related to bone formation. Excessive cholesterol may cause osteoporosis, cholesterol and its metabolites affect bone homeostasis by regulating the proliferation and stimulation of osteoblasts and osteoclasts. Therefore, antagonism of elevated cholesterol levels may be a potential strategy to prevent osteoporosis. There is sufficient evidence to support the use of bisphosphonates and statin drugs for osteoporosis in the clinic. Therefore, in view of the aggravation of the aging problem, we summarize the intracellular mechanism of cholesterol homeostasis and its relationship with osteoporosis (including cholesterol and cholesterol oxidation products (COPs) in osteoporosis). Furthermore, the current clinical cholesterol-lowering drugs for osteoporosis were also summarized, as are new and promising therapies (cell-based therapies (e.g., stem cells) and biomaterial-delivered target drug therapies for osteoporosis as well).
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Affiliation(s)
- Chuncha Bao
- Department of Rehabilitation Medicine, West China Hospital, Sichuan University, Chengdu 610041, Sichuan, People's Republic of China
- Key Laboratory of Rehabilitation Medicine, Rehabilitation Medicine Center, West China Hospital, Sichuan University, Chengdu 610041, People's Republic of China
| | - Tao Wu
- Department of Rehabilitation Medicine, West China Hospital, Sichuan University, Chengdu 610041, Sichuan, People's Republic of China
- Key Laboratory of Rehabilitation Medicine, Rehabilitation Medicine Center, West China Hospital, Sichuan University, Chengdu 610041, People's Republic of China
| | - Siyi Zhu
- Department of Rehabilitation Medicine, West China Hospital, Sichuan University, Chengdu 610041, Sichuan, People's Republic of China
- Key Laboratory of Rehabilitation Medicine, Rehabilitation Medicine Center, West China Hospital, Sichuan University, Chengdu 610041, People's Republic of China
| | - Xiaoyi Wang
- Department of Rehabilitation Medicine, West China Hospital, Sichuan University, Chengdu 610041, Sichuan, People's Republic of China
- Key Laboratory of Rehabilitation Medicine, Rehabilitation Medicine Center, West China Hospital, Sichuan University, Chengdu 610041, People's Republic of China
| | - Yujia Zhang
- Department of Rehabilitation Medicine, West China Hospital, Sichuan University, Chengdu 610041, Sichuan, People's Republic of China
- Key Laboratory of Rehabilitation Medicine, Rehabilitation Medicine Center, West China Hospital, Sichuan University, Chengdu 610041, People's Republic of China
| | - Xiangxiu Wang
- Department of Rehabilitation Medicine, West China Hospital, Sichuan University, Chengdu 610041, Sichuan, People's Republic of China
- Key Laboratory of Rehabilitation Medicine, Rehabilitation Medicine Center, West China Hospital, Sichuan University, Chengdu 610041, People's Republic of China
| | - Lin Yang
- Department of Rehabilitation Medicine, West China Hospital, Sichuan University, Chengdu 610041, Sichuan, People's Republic of China
- Key Laboratory of Rehabilitation Medicine, Rehabilitation Medicine Center, West China Hospital, Sichuan University, Chengdu 610041, People's Republic of China
| | - Chengqi He
- Department of Rehabilitation Medicine, West China Hospital, Sichuan University, Chengdu 610041, Sichuan, People's Republic of China
- Key Laboratory of Rehabilitation Medicine, Rehabilitation Medicine Center, West China Hospital, Sichuan University, Chengdu 610041, People's Republic of China
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Rosenhouse-Dantsker A, Gazgalis D, Logothetis DE. PI(4,5)P 2 and Cholesterol: Synthesis, Regulation, and Functions. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023; 1422:3-59. [PMID: 36988876 DOI: 10.1007/978-3-031-21547-6_1] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
Abstract
Phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) is the most abundant membrane phosphoinositide and cholesterol is an essential component of the plasma membrane (PM). Both lipids play key roles in a variety of cellular functions including as signaling molecules and major regulators of protein function. This chapter provides an overview of these two important lipids. Starting from a brief description of their structure, synthesis, and regulation, the chapter continues to describe the primary functions and signaling processes in which PI(4,5)P2 and cholesterol are involved. While PI(4,5)P2 and cholesterol can act independently, they often act in concert or affect each other's impact. The chapters in this volume on "Cholesterol and PI(4,5)P2 in Vital Biological Functions: From Coexistence to Crosstalk" focus on the emerging relationship between cholesterol and PI(4,5)P2 in a variety of biological systems and processes. In this chapter, the next section provides examples from the ion channel field demonstrating that PI(4,5)P2 and cholesterol can act via common mechanisms. The chapter ends with a discussion of future directions.
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Affiliation(s)
| | - Dimitris Gazgalis
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, Bouvé College of Health Sciences, Northeastern University, Boston, MA, USA
| | - Diomedes E Logothetis
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, Bouvé College of Health Sciences, Northeastern University, Boston, MA, USA
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7
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Duan Y, Gong K, Xu S, Zhang F, Meng X, Han J. Regulation of cholesterol homeostasis in health and diseases: from mechanisms to targeted therapeutics. Signal Transduct Target Ther 2022; 7:265. [PMID: 35918332 PMCID: PMC9344793 DOI: 10.1038/s41392-022-01125-5] [Citation(s) in RCA: 79] [Impact Index Per Article: 39.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Revised: 07/04/2022] [Accepted: 07/12/2022] [Indexed: 12/13/2022] Open
Abstract
Disturbed cholesterol homeostasis plays critical roles in the development of multiple diseases, such as cardiovascular diseases (CVD), neurodegenerative diseases and cancers, particularly the CVD in which the accumulation of lipids (mainly the cholesteryl esters) within macrophage/foam cells underneath the endothelial layer drives the formation of atherosclerotic lesions eventually. More and more studies have shown that lowering cholesterol level, especially low-density lipoprotein cholesterol level, protects cardiovascular system and prevents cardiovascular events effectively. Maintaining cholesterol homeostasis is determined by cholesterol biosynthesis, uptake, efflux, transport, storage, utilization, and/or excretion. All the processes should be precisely controlled by the multiple regulatory pathways. Based on the regulation of cholesterol homeostasis, many interventions have been developed to lower cholesterol by inhibiting cholesterol biosynthesis and uptake or enhancing cholesterol utilization and excretion. Herein, we summarize the historical review and research events, the current understandings of the molecular pathways playing key roles in regulating cholesterol homeostasis, and the cholesterol-lowering interventions in clinics or in preclinical studies as well as new cholesterol-lowering targets and their clinical advances. More importantly, we review and discuss the benefits of those interventions for the treatment of multiple diseases including atherosclerotic cardiovascular diseases, obesity, diabetes, nonalcoholic fatty liver disease, cancer, neurodegenerative diseases, osteoporosis and virus infection.
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Affiliation(s)
- Yajun Duan
- Department of Cardiology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China.,Key Laboratory of Metabolism and Regulation for Major Diseases of Anhui Higher Education Institutes, College of Food and Biological Engineering, Hefei University of Technology, Hefei, China
| | - Ke Gong
- Key Laboratory of Metabolism and Regulation for Major Diseases of Anhui Higher Education Institutes, College of Food and Biological Engineering, Hefei University of Technology, Hefei, China
| | - Suowen Xu
- Department of Cardiology, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China
| | - Feng Zhang
- Key Laboratory of Metabolism and Regulation for Major Diseases of Anhui Higher Education Institutes, College of Food and Biological Engineering, Hefei University of Technology, Hefei, China
| | - Xianshe Meng
- Key Laboratory of Metabolism and Regulation for Major Diseases of Anhui Higher Education Institutes, College of Food and Biological Engineering, Hefei University of Technology, Hefei, China
| | - Jihong Han
- Key Laboratory of Metabolism and Regulation for Major Diseases of Anhui Higher Education Institutes, College of Food and Biological Engineering, Hefei University of Technology, Hefei, China. .,College of Life Sciences, Key Laboratory of Bioactive Materials of Ministry of Education, State Key Laboratory of Medicinal Chemical Biology, Nankai University, Tianjin, China.
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8
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罗 娜, 时 荣, 代 荣, 缪 洪. [Cholesterol Metabolism and Tumor Immunity]. SICHUAN DA XUE XUE BAO. YI XUE BAN = JOURNAL OF SICHUAN UNIVERSITY. MEDICAL SCIENCE EDITION 2022; 53:335-341. [PMID: 35332739 PMCID: PMC10409372 DOI: 10.12182/20220360202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Indexed: 06/14/2023]
Abstract
Cholesterol, an important lipid molecule of organisms, is involved in the formation of cell membrane structure, bile acid metabolism and steroid hormone synthesis, playing an important role in the regulation of cell structure and functions. In recent years, a large number of studies have shown that cholesterol metabolism is reprogrammed during tumor formation and development. In addition to directly affecting the biological behavior of tumor cells, cholesterol metabolic reprogramming also regulates the antitumor activity of immune cells in the tumor microenvironment. We reviewed herein the cholesterol metabolism reprogramming of and interactions among immune cells including myeloid-derived suppressor cells (MDSCs), tumor-associated macrophages (TAMs), dendritic cells (DCs), and T cells in the tumor microenvironment. However, the relationship between cholesterol metabolism and tumor immunity in tumor microenvironment is complex and diversified. The differences and similarities of cholesterol metabolism reprogramming in tumor microenvironment in regulating immune cell activity and the specific regulatory mechanism are still unresolved issues. Targeted intervention of the cholesterol metabolism pathway of immune cells is expected to become a new strategy of cholesterol metabolism in tumor immunotherapy.
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Affiliation(s)
- 娜 罗
- 西南医科大学基础医学院 (泸州 646000)College of Basic Medical Sciences, Southwest Medical University, Luzhou 646000, China
- 陆军军医大学(第三军医大学)基础医学院 生物化学与分子生物学教研室 (重庆 400038)Department of Biochemistry and Molecular Biology, College of Basic Medical Sciences, Army Medical University (Third Military Medical University), Chongqing 400038, China
| | - 荣臣 时
- 西南医科大学基础医学院 (泸州 646000)College of Basic Medical Sciences, Southwest Medical University, Luzhou 646000, China
| | - 荣阳 代
- 西南医科大学基础医学院 (泸州 646000)College of Basic Medical Sciences, Southwest Medical University, Luzhou 646000, China
| | - 洪明 缪
- 西南医科大学基础医学院 (泸州 646000)College of Basic Medical Sciences, Southwest Medical University, Luzhou 646000, China
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9
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Neijenhuis T, van Keulen SC, Bonvin AMJJ. Interface refinement of low- to medium-resolution Cryo-EM complexes using HADDOCK2.4. Structure 2022; 30:476-484.e3. [PMID: 35216656 DOI: 10.1016/j.str.2022.02.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 11/25/2021] [Accepted: 01/28/2022] [Indexed: 10/19/2022]
Abstract
A wide range of cellular processes requires the formation of multimeric protein complexes. The rise of cryo-electron microscopy (cryo-EM) has enabled the structural characterization of these protein assemblies. The density maps produced can, however, still suffer from limited resolution, impeding the process of resolving structures at atomic resolution. In order to solve this issue, monomers can be fitted into low- to medium-resolution maps. Unfortunately, the models produced frequently contain atomic clashes at the protein-protein interfaces (PPIs), as intermolecular interactions are typically not considered during monomer fitting. Here, we present a refinement approach based on HADDOCK2.4 to remove intermolecular clashes and optimize PPIs. A dataset of 14 cryo-EM complexes was used to test eight protocols. The best-performing protocol, consisting of a semi-flexible simulated annealing refinement with centroid restraints on the monomers, was able to decrease intermolecular atomic clashes by 98% without significantly deteriorating the quality of the cryo-EM density fit.
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Affiliation(s)
- Tim Neijenhuis
- Computational Structural Biology Group, Bijvoet Center for Biomolecular Research, Science for Life, Faculty of Science - Chemistry, Utrecht University, Padualaan 8, 3584 CH, Utrecht, the Netherlands
| | - Siri C van Keulen
- Computational Structural Biology Group, Bijvoet Center for Biomolecular Research, Science for Life, Faculty of Science - Chemistry, Utrecht University, Padualaan 8, 3584 CH, Utrecht, the Netherlands
| | - Alexandre M J J Bonvin
- Computational Structural Biology Group, Bijvoet Center for Biomolecular Research, Science for Life, Faculty of Science - Chemistry, Utrecht University, Padualaan 8, 3584 CH, Utrecht, the Netherlands.
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10
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Zou H, Yang N, Zhang X, Chen HW. RORγ is a context-specific master regulator of cholesterol biosynthesis and an emerging therapeutic target in cancer and autoimmune diseases. Biochem Pharmacol 2021; 196:114725. [PMID: 34384758 DOI: 10.1016/j.bcp.2021.114725] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 08/04/2021] [Accepted: 08/05/2021] [Indexed: 01/04/2023]
Abstract
Aberrant cholesterol metabolism and homeostasis in the form of elevated cholesterol biosynthesis and dysregulated efflux and metabolism is well recognized as a major feature of metabolic reprogramming in solid tumors. Recent studies have emphasized on major drivers and regulators such as Myc, mutant p53, SREBP2, LXRs and oncogenic signaling pathways that play crucial roles in tumor cholesterol metabolic reprogramming. Therapeutics such as statins targeting the mevalonate pathway were tried at the clinic without showing consistent benefits to cancer patients. Nuclear receptors are prominent regulators of mammalian metabolism. Their de-regulation often drives tumorigenesis. RORγ and its immune cell-specific isoform RORγt play important functions in control of mammalian metabolism, circadian rhythm and immune responses. Although RORγ, together with its closely related members RORα and RORβ were identified initially as orphan receptors, recent studies strongly support the conclusion that specific intermediates and metabolites of cholesterol pathways serve as endogenous ligands of RORγ. More recent studies also reveal a critical role of RORγ in tumorigenesis through major oncogenic pathways including acting a new master-like regulator of tumor cholesterol biosynthesis program. Importantly, an increasing number of RORγ orthosteric and allosteric ligands are being identified that display potent activities in blocking tumor growth and autoimmune disorders in preclinical models. This review summarizes the recent preclinical and clinical progress on RORγ with emphasis on its role in reprogramming tumor cholesterol metabolism and its regulation. It will also discuss RORγ functional mechanisms, context-specificity and its value as a therapeutic target for effective cancer treatment.
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Affiliation(s)
- Hongye Zou
- Department of Biochemistry and Molecular Medicine, University of California, Davis, School of Medicine, Sacramento, California, USA
| | - Nianxin Yang
- Department of Biochemistry and Molecular Medicine, University of California, Davis, School of Medicine, Sacramento, California, USA
| | - Xiong Zhang
- Department of Biochemistry and Molecular Medicine, University of California, Davis, School of Medicine, Sacramento, California, USA
| | - Hong-Wu Chen
- Department of Biochemistry and Molecular Medicine, University of California, Davis, School of Medicine, Sacramento, California, USA; UC Davis Comprehensive Cancer Center, University of California, Davis, Sacramento, California, USA; VA Northern California Health Care System, Mather, California, USA.
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11
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Yan R, Cao P, Song W, Qian H, Du X, Coates HW, Zhao X, Li Y, Gao S, Gong X, Liu X, Sui J, Lei J, Yang H, Brown AJ, Zhou Q, Yan C, Yan N. A structure of human Scap bound to Insig-2 suggests how their interaction is regulated by sterols. Science 2021; 371:science.abb2224. [PMID: 33446483 DOI: 10.1126/science.abb2224] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2020] [Revised: 07/31/2020] [Accepted: 01/06/2021] [Indexed: 12/22/2022]
Abstract
The sterol regulatory element-binding protein (SREBP) pathway controls cellular homeostasis of sterols. The key players in this pathway, Scap and Insig-1 and -2, are membrane-embedded sterol sensors. The 25-hydroxycholesterol (25HC)-dependent association of Scap and Insig acts as the master switch for the SREBP pathway. Here, we present cryo-electron microscopy analysis of the human Scap and Insig-2 complex in the presence of 25HC, with the transmembrane (TM) domains determined at an average resolution of 3.7 angstrom. The sterol-sensing domain in Scap and all six TMs in Insig-2 were resolved. A 25HC molecule is sandwiched between the S4 to S6 segments in Scap and TMs 3 and 4 in Insig-2 in the luminal leaflet of the membrane. Unwinding of the middle of the Scap-S4 segment is crucial for 25HC binding and Insig association.
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Affiliation(s)
- Renhong Yan
- Westlake Laboratory of Life Sciences and Biomedicine, Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou 310024, Zhejiang Province, China.,Institute of Biology, Westlake Institute for Advanced Study, Hangzhou 310024, Zhejiang Province, China
| | - Pingping Cao
- State Key Laboratory of Membrane Biology, Beijing Advanced Innovation Center for Structural Biology, Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Wenqi Song
- State Key Laboratory of Membrane Biology, Beijing Advanced Innovation Center for Structural Biology, Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Hongwu Qian
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA
| | - Ximing Du
- School of Biotechnology and Biomolecular Science, University of New South Wales, Sydney, NSW 2052, Australia
| | - Hudson W Coates
- School of Biotechnology and Biomolecular Science, University of New South Wales, Sydney, NSW 2052, Australia
| | - Xin Zhao
- State Key Laboratory of Membrane Biology, Beijing Advanced Innovation Center for Structural Biology, Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Yaning Li
- State Key Laboratory of Membrane Biology, Beijing Advanced Innovation Center for Structural Biology, Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Shuai Gao
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA
| | - Xin Gong
- Department of Biology, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China
| | - Ximing Liu
- National Institute of Biological Sciences (NIBS), Beijing 102206, China
| | - Jianhua Sui
- National Institute of Biological Sciences (NIBS), Beijing 102206, China.,Tsinghua Institute of Multidisciplinary Biomedical Research, Tsinghua University, Beijing 102206, China
| | - Jianlin Lei
- Technology Center for Protein Sciences, Ministry of Education Key Laboratory of Protein Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Hongyuan Yang
- School of Biotechnology and Biomolecular Science, University of New South Wales, Sydney, NSW 2052, Australia
| | - Andrew J Brown
- School of Biotechnology and Biomolecular Science, University of New South Wales, Sydney, NSW 2052, Australia
| | - Qiang Zhou
- Westlake Laboratory of Life Sciences and Biomedicine, Key Laboratory of Structural Biology of Zhejiang Province, School of Life Sciences, Westlake University, Hangzhou 310024, Zhejiang Province, China.,Institute of Biology, Westlake Institute for Advanced Study, Hangzhou 310024, Zhejiang Province, China
| | - Chuangye Yan
- State Key Laboratory of Membrane Biology, Beijing Advanced Innovation Center for Structural Biology, Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China.
| | - Nieng Yan
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA.
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12
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Juarez D, Fruman DA. Targeting the Mevalonate Pathway in Cancer. Trends Cancer 2021; 7:525-540. [PMID: 33358111 DOI: 10.1016/j.trecan.2020.11.008] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 11/21/2020] [Accepted: 11/23/2020] [Indexed: 02/06/2023]
Abstract
The mevalonate synthesis inhibitors, statins, are mainstay therapeutics for cholesterol management and cardiovascular health. Thirty years of research have uncovered supportive roles for the mevalonate pathway in numerous cellular processes that support oncogenesis, most recently macropinocytosis. Central to the diverse mechanisms of statin sensitivity is an acquired dependence on one mevalonate pathway output, protein geranylgeranylation. New chemical prenylation probes and the discovery of a novel geranylgeranyl transferase hold promise to deepen our understanding of statin mechanisms of action. Further, insights into statin selection and the counterproductive role of dietary geranylgeraniol highlight how we should assess statins in the clinic. Lastly, rational combination strategies preview how statins will enter the oncology toolbox.
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Affiliation(s)
- Dennis Juarez
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA 92697, USA
| | - David A Fruman
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA 92697, USA.
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13
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Identification of a degradation signal at the carboxy terminus of SREBP2: A new role for this domain in cholesterol homeostasis. Proc Natl Acad Sci U S A 2020; 117:28080-28091. [PMID: 33106423 DOI: 10.1073/pnas.2018578117] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Lipid homeostasis in animal cells is maintained by sterol regulatory element-binding proteins (SREBPs), membrane-bound transcription factors whose proteolytic activation requires the cholesterol-sensing membrane protein Scap. In endoplasmic reticulum (ER) membranes, the carboxyl-terminal domain (CTD) of SREBPs binds to the CTD of Scap. When cholesterol levels are low, Scap escorts SREBPs from the ER to the Golgi, where the actions of two proteases release the amino-terminal domains of SREBPs that travel to the nucleus to up-regulate expression of lipogenic genes. The CTD of SREBP remains bound to Scap but must be eliminated so that Scap can be recycled to bind and transport additional SREBPs. Here, we provide insights into how this occurs by performing a detailed molecular dissection of the CTD of SREBP2, one of three SREBP isoforms expressed in mammals. We identify a degradation signal comprised of seven noncontiguous amino acids encoded in exon 19 that mediates SREBP2's proteasomal degradation in the absence of Scap. When bound to the CTD of Scap, this signal is masked and SREBP2 is stabilized. Binding to Scap requires an arginine residue in exon 18 of SREBP2. After SREBP2 is cleaved in Golgi, its CTD remains bound to Scap and returns to the ER with Scap where it is eliminated by proteasomal degradation. The Scap-binding motif, but not the degradation signal, is conserved in SREBP1. SREBP1's stability is determined by a degradation signal in a different region of its CTD. These findings highlight a previously unknown role for the CTD of SREBPs in regulating SREBP activity.
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14
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Cai W, Zhou W, Han Z, Lei J, Zhuang J, Zhu P, Wu X, Yuan W. Master regulator genes and their impact on major diseases. PeerJ 2020; 8:e9952. [PMID: 33083114 PMCID: PMC7546222 DOI: 10.7717/peerj.9952] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Accepted: 08/25/2020] [Indexed: 01/10/2023] Open
Abstract
Master regulator genes (MRGs) have become a hot topic in recent decades. They not only affect the development of tissue and organ systems but also play a role in other signal pathways by regulating additional MRGs. Because a MRG can regulate the concurrent expression of several genes, its mutation often leads to major diseases. Moreover, the occurrence of many tumors and cardiovascular and nervous system diseases are closely related to MRG changes. With the development in omics technology, an increasing amount of investigations will be directed toward MRGs because their regulation involves all aspects of an organism’s development. This review focuses on the definition and classification of MRGs as well as their influence on disease regulation.
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Affiliation(s)
- Wanwan Cai
- The Center for Heart Development, State Key Laboratory of Development Biology of Freshwater Fish, Key Laboratory of MOE for Development Biology and Protein Chemistry, College of Life Sciences, Hunan Normal University, Changsha, Hunan, China
| | - Wanbang Zhou
- College of Physical Education, Hunan Normal University, Changsha, Hunan, China
| | - Zhe Han
- University of Maryland School of Medicine, Center for Precision Disease Modeling, Baltimore, MD, USA
| | - Junrong Lei
- College of Physical Education, Hunan Normal University, Changsha, Hunan, China
| | - Jian Zhuang
- Guangdong Cardiovascular Institute, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Department of Cardiac Surgery, Guangzhou, Guangdong, China
| | - Ping Zhu
- Guangdong Cardiovascular Institute, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Department of Cardiac Surgery, Guangzhou, Guangdong, China
| | - Xiushan Wu
- The Center for Heart Development, State Key Laboratory of Development Biology of Freshwater Fish, Key Laboratory of MOE for Development Biology and Protein Chemistry, College of Life Sciences, Hunan Normal University, Changsha, Hunan, China
| | - Wuzhou Yuan
- The Center for Heart Development, State Key Laboratory of Development Biology of Freshwater Fish, Key Laboratory of MOE for Development Biology and Protein Chemistry, College of Life Sciences, Hunan Normal University, Changsha, Hunan, China
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15
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Mechanisms and regulation of cholesterol homeostasis. Nat Rev Mol Cell Biol 2019; 21:225-245. [DOI: 10.1038/s41580-019-0190-7] [Citation(s) in RCA: 450] [Impact Index Per Article: 90.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/24/2019] [Indexed: 12/14/2022]
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16
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Xiang R, Fan LL, Huang H, Chen YQ, He W, Guo S, Li JJ, Jin JY, Du R, Yan R, Xia K. Increased Reticulon 3 (RTN3) Leads to Obesity and Hypertriglyceridemia by Interacting With Heat Shock Protein Family A (Hsp70) Member 5 (HSPA5). Circulation 2019; 138:1828-1838. [PMID: 29716941 DOI: 10.1161/circulationaha.117.030718] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND Reticulon 3 (RTN3) is an endoplasmic reticulum protein that has previously been shown to play a role in neurodegenerative diseases, but little is known about its role in lipid metabolism. METHODS Obese patients (n=149), hypertriglyceridemic patients (n=343), and healthy control subjects (n=84) were enrolled to assess their levels of RTN3. To explore the pathophysiological roles of RTN3 in the control of lipid metabolism, we used transgenic mice overexpressing the wild-type human RTN3 gene, the RTN3-null transgenic mouse model, and multiple Caenorhabditis legans strains for molecular characterization. The underlying mechanisms were studied with 3T3L1 cell cultures in vitro. RESULTS We report that overexpressed RTN3 in mice induces obesity and higher accumulation of triglycerides. Increased RTN3 expression is also found in patients with obesity and hypertriglyceridemia. We reveal that RTN3 plays critical roles in regulating the biosynthesis and storage of triglycerides and in controlling lipid droplet expansion. Mechanistically, RTN3 regulates these events through its interactions with heat shock protein family A (Hsp70) member 5, and this enhanced interaction increases sterol regulatory element-binding protein 1c and AMP-activated kinase activity. CONCLUSIONS This study provides evidence for a role of RTN3 in inducing obesity and triglyceride accumulation and suggests that inhibiting the expression of RTN3 in fat tissue may be a novel therapeutic approach to treat obesity and hypertriglyceridemia.
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Affiliation(s)
- Rong Xiang
- Department of Cell Biology, School of Life Sciences, Central South University, Changsha, China (R.X., L.-l.F., H.H., S.G., J.-J.L., J.-y.J., R.D., K.X.)
| | - Liang-Liang Fan
- Department of Cell Biology, School of Life Sciences, Central South University, Changsha, China (R.X., L.-l.F., H.H., S.G., J.-J.L., J.-y.J., R.D., K.X.)
| | - Hao Huang
- Department of Cell Biology, School of Life Sciences, Central South University, Changsha, China (R.X., L.-l.F., H.H., S.G., J.-J.L., J.-y.J., R.D., K.X.)
| | - Ya-Qin Chen
- Department of Cardiology, Second Xiangya Hospital of Central South University, Changsha, China (Y.-q.C.)
| | - Wanxia He
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic Foundation, OH (W.H., R.Y.)
| | - Shuai Guo
- Department of Cell Biology, School of Life Sciences, Central South University, Changsha, China (R.X., L.-l.F., H.H., S.G., J.-J.L., J.-y.J., R.D., K.X.)
| | - Jing-Jing Li
- Department of Cell Biology, School of Life Sciences, Central South University, Changsha, China (R.X., L.-l.F., H.H., S.G., J.-J.L., J.-y.J., R.D., K.X.)
| | - Jie-Yuan Jin
- Department of Cell Biology, School of Life Sciences, Central South University, Changsha, China (R.X., L.-l.F., H.H., S.G., J.-J.L., J.-y.J., R.D., K.X.)
| | - Ran Du
- Department of Cell Biology, School of Life Sciences, Central South University, Changsha, China (R.X., L.-l.F., H.H., S.G., J.-J.L., J.-y.J., R.D., K.X.)
| | - Riqiang Yan
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic Foundation, OH (W.H., R.Y.)
| | - Kun Xia
- Department of Cell Biology, School of Life Sciences, Central South University, Changsha, China (R.X., L.-l.F., H.H., S.G., J.-J.L., J.-y.J., R.D., K.X.)
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17
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Burr R, Espenshade PJ. Oxygen-responsive transcriptional regulation of lipid homeostasis in fungi: Implications for anti-fungal drug development. Semin Cell Dev Biol 2017; 81:110-120. [PMID: 28851600 DOI: 10.1016/j.semcdb.2017.08.043] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Revised: 08/08/2017] [Accepted: 08/22/2017] [Indexed: 01/01/2023]
Abstract
Low oxygen adaptation is essential for aerobic fungi that must survive in varied oxygen environments. Pathogenic fungi in particular must adapt to the low oxygen host tissue environment in order to cause infection. Maintenance of lipid homeostasis is especially important for cell growth and proliferation, and is a highly oxygen-dependent process. In this review, we focus on recent advances in our understanding of the transcriptional regulation and coordination of the low oxygen response across fungal species, paying particular attention to pathogenic fungi. Comparison of lipid homeostasis pathways in these organisms suggests common mechanisms of transcriptional regulation and points toward untapped potential to target low oxygen adaptation in antifungal development.
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Affiliation(s)
- Risa Burr
- Department of Cell Biology, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Peter J Espenshade
- Department of Cell Biology, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
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18
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Brown MS, Radhakrishnan A, Goldstein JL. Retrospective on Cholesterol Homeostasis: The Central Role of Scap. Annu Rev Biochem 2017; 87:783-807. [PMID: 28841344 DOI: 10.1146/annurev-biochem-062917-011852] [Citation(s) in RCA: 298] [Impact Index Per Article: 42.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Scap is a polytopic membrane protein that functions as a molecular machine to control the cholesterol content of membranes in mammalian cells. In the 21 years since our laboratory discovered Scap, we have learned how it binds sterol regulatory element-binding proteins (SREBPs) and transports them from the endoplasmic reticulum (ER) to the Golgi for proteolytic processing. Proteolysis releases the SREBP transcription factor domains, which enter the nucleus to promote cholesterol synthesis and uptake. When cholesterol in ER membranes exceeds a threshold, the sterol binds to Scap, triggering several conformational changes that prevent the Scap-SREBP complex from leaving the ER. As a result, SREBPs are no longer processed, cholesterol synthesis and uptake are repressed, and cholesterol homeostasis is restored. This review focuses on the four domains of Scap that undergo concerted conformational changes in response to cholesterol binding. The data provide a molecular mechanism for the control of lipids in cell membranes.
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Affiliation(s)
- Michael S Brown
- Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA; ;
| | - Arun Radhakrishnan
- Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA; ;
| | - Joseph L Goldstein
- Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA; ;
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19
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Kuan YC, Hashidume T, Shibata T, Uchida K, Shimizu M, Inoue J, Sato R. Heat Shock Protein 90 Modulates Lipid Homeostasis by Regulating the Stability and Function of Sterol Regulatory Element-binding Protein (SREBP) and SREBP Cleavage-activating Protein. J Biol Chem 2016; 292:3016-3028. [PMID: 28003358 DOI: 10.1074/jbc.m116.767277] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Revised: 12/14/2016] [Indexed: 12/18/2022] Open
Abstract
Sterol regulatory element-binding proteins (SREBPs) are the key transcription factors that modulate lipid biosynthesis. SREBPs are synthesized as endoplasmic reticulum-bound precursors that require proteolytic activation in the Golgi apparatus. The stability and maturation of precursor SREBPs depend on their binding to SREBP cleavage-activating protein (SCAP), which escorts the SCAP-SREBP complex to the Golgi apparatus. In this study, we identified heat shock protein (HSP) 90 as a novel SREBP regulator that binds to and stabilizes SCAP-SREBP. In HepG2 cells, HSP90 inhibition led to proteasome-dependent degradation of SCAP-SREBP, which resulted in the down-regulation of SREBP target genes and the reduction in intracellular triglyceride and cholesterol levels. We also demonstrated in vivo that HSP90 inhibition decreased SCAP-SREBP protein, down-regulated SREBP target genes, and reduced lipids levels in mouse livers. We propose that HSP90 plays an indispensable role in SREBP regulation by stabilizing the SCAP-SREBP complex, facilitating the activation of SREBP to maintain lipids homeostasis.
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Affiliation(s)
| | | | - Takahiro Shibata
- the Department of Applied Molecular Biosciences, Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan, and
| | - Koji Uchida
- the Department of Applied Molecular Biosciences, Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan, and
| | | | - Jun Inoue
- From the Food Biochemistry Laboratory and
| | - Ryuichiro Sato
- From the Food Biochemistry Laboratory and .,the Nutri-Life Science Laboratory, Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, University of Tokyo, Tokyo 113-8657, Japan.,AMED-CREST, Japan Agency for Medical Research and Development, Chiyoda-ku, Tokyo 100-0004, Japan
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