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Choi M, Jeong K, Pak Y. Caveolin-2 controls preadipocyte survival in the mitotic clonal expansion for adipogenesis. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2024; 1871:119793. [PMID: 39038612 DOI: 10.1016/j.bbamcr.2024.119793] [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: 03/21/2024] [Revised: 06/11/2024] [Accepted: 06/27/2024] [Indexed: 07/24/2024]
Abstract
Here, we report that Caveolin-2 (Cav-2) is a cell cycle regulator in the mitotic clonal expansion (MCE) for adipogenesis. For the G2/M phase transition and re-entry into the G1 phase, dephosphorylated Cav-2 by protein tyrosine phosphatase 1B (PTP1B) controlled epigenetic activation of Ccnb1, Cdk1, and p21 in a lamin A/C-dependent manner, thereby ensuring the survival of preadipocytes. Cav-2, associated with lamin A/C, recruited the repressed promoters of Ccnb1 and Cdk1 for activation, and disengaged the active promoter of p21 from lamin A/C for inactivation through histone H3 modifications at the nuclear periphery. Cav-2 deficiency abrogated the histone H3 modifications and impeded the transactivation of Ccnb1, Cdk1, and p21, leading to a delay in mitotic entry, retardation of re-entry into G1 phase, and the apoptotic cell death of preadipocytes. Re-expression of Cav-2 restored the G2/M phase transition and G1 phase re-entry, preadipocyte survival, and adipogenesis in Cav-2-deficient preadipocytes. Our study uncovers a novel mechanism by which cell cycle transition and apoptotic cell death are controlled for adipocyte hyperplasia.
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Affiliation(s)
- Moonjeong Choi
- Division of Life Science, Graduate School of Applied Life Science, PMBBRC, Gyeongsang National University, Jinju 52828, Republic of Korea
| | - Kyuho Jeong
- Department of Biochemistry, College of Medicine, Dongguk University, Gyeongju 38066, Republic of Korea
| | - Yunbae Pak
- Division of Life Science, Graduate School of Applied Life Science, PMBBRC, Gyeongsang National University, Jinju 52828, Republic of Korea.
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2
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Choi M, Lee J, Jeong K, Pak Y. Caveolin-2 palmitoylation turnover facilitates insulin receptor substrate-1-directed lipid metabolism by insulin receptor tyrosine kinase. Biochim Biophys Acta Mol Basis Dis 2024; 1870:167173. [PMID: 38631410 DOI: 10.1016/j.bbadis.2024.167173] [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: 10/19/2023] [Revised: 03/13/2024] [Accepted: 04/08/2024] [Indexed: 04/19/2024]
Abstract
Here, we show that insulin induces palmitoylation turnover of Caveolin-2 (Cav-2) in adipocytes. Acyl protein thioesterases-1 (APT1) catalyzes Cav-2 depalmitoylation, and zinc finger DHHC domain-containing protein palmitoyltransferase 21 (ZDHHC21) repalmitoylation of the depalmitoylated Cav-2 for the turnover, thereby controlling insulin receptor (IR)-Cav-2-insulin receptor substrate-1 (IRS-1)-Akt-driven signaling. Insulin-induced palmitoylation turnover of Cav-2 facilitated glucose uptake and fat storage through induction of lipogenic genes. Cav-2-, APT1-, and ZDHHC21-deficient adipocytes, however, showed increased induction of lipolytic genes and glycerol release. In addition, white adipose tissues from insulin sensitive and resistant obese patients exhibited augmented expression of LYPLA1 (APT1) and ZDHHC20 (ZDHHC20). Our study identifies the specific enzymes regulating Cav-2 palmitoylation turnover, and reveals a new mechanism by which insulin-mediated lipid metabolism is controlled in adipocytes.
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Affiliation(s)
- Moonjeong Choi
- Division of Life Science, Graduate School of Applied Life Science (BK21 Plus Program), PMBBRC, Gyeongsang National University, Jinju 52828, Republic of Korea
| | - Jaewoong Lee
- Department of Anatomy and Convergence Medical Science, College of Medicine, Institute of Medical Sciences, Gyeongsang National University, Jinju 52727, Republic of Korea
| | - Kyuho Jeong
- Department of Biochemistry, College of Medicine, Dongguk University, 123 Dongdae-ro, Gyeongju 38066, Republic of Korea
| | - Yunbae Pak
- Division of Life Science, Graduate School of Applied Life Science (BK21 Plus Program), PMBBRC, Gyeongsang National University, Jinju 52828, Republic of Korea.
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3
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Bogaert A, Fijalkowska D, Staes A, Van de Steene T, Vuylsteke M, Stadler C, Eyckerman S, Spirohn K, Hao T, Calderwood MA, Gevaert K. N-terminal proteoforms may engage in different protein complexes. Life Sci Alliance 2023; 6:e202301972. [PMID: 37316325 PMCID: PMC10267514 DOI: 10.26508/lsa.202301972] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Revised: 05/26/2023] [Accepted: 05/30/2023] [Indexed: 06/16/2023] Open
Abstract
Alternative translation initiation and alternative splicing may give rise to N-terminal proteoforms, proteins that differ at their N-terminus compared with their canonical counterparts. Such proteoforms can have altered localizations, stabilities, and functions. Although proteoforms generated from splice variants can be engaged in different protein complexes, it remained to be studied to what extent this applies to N-terminal proteoforms. To address this, we mapped the interactomes of several pairs of N-terminal proteoforms and their canonical counterparts. First, we generated a catalogue of N-terminal proteoforms found in the HEK293T cellular cytosol from which 22 pairs were selected for interactome profiling. In addition, we provide evidence for the expression of several N-terminal proteoforms, identified in our catalogue, across different human tissues, as well as tissue-specific expression, highlighting their biological relevance. Protein-protein interaction profiling revealed that the overlap of the interactomes for both proteoforms is generally high, showing their functional relation. We also showed that N-terminal proteoforms can be engaged in new interactions and/or lose several interactions compared with their canonical counterparts, thus further expanding the functional diversity of proteomes.
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Affiliation(s)
- Annelies Bogaert
- VIB Center for Medical Biotechnology, VIB, Ghent, Belgium
- Department of Biomolecular Medicine, Ghent University, Ghent, Belgium
| | - Daria Fijalkowska
- VIB Center for Medical Biotechnology, VIB, Ghent, Belgium
- Department of Biomolecular Medicine, Ghent University, Ghent, Belgium
| | - An Staes
- VIB Center for Medical Biotechnology, VIB, Ghent, Belgium
- Department of Biomolecular Medicine, Ghent University, Ghent, Belgium
| | - Tessa Van de Steene
- VIB Center for Medical Biotechnology, VIB, Ghent, Belgium
- Department of Biomolecular Medicine, Ghent University, Ghent, Belgium
| | | | - Charlotte Stadler
- Department of Protein Science, KTH Royal Institute of Technology and Science for Life Laboratories, Stockholm, Sweden
| | - Sven Eyckerman
- VIB Center for Medical Biotechnology, VIB, Ghent, Belgium
- Department of Biomolecular Medicine, Ghent University, Ghent, Belgium
| | - Kerstin Spirohn
- Center for Cancer Systems Biology (CCSB), Dana-Farber Cancer Institute, Boston, MA, USA
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA, USA
| | - Tong Hao
- Center for Cancer Systems Biology (CCSB), Dana-Farber Cancer Institute, Boston, MA, USA
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA, USA
| | - Michael A Calderwood
- Center for Cancer Systems Biology (CCSB), Dana-Farber Cancer Institute, Boston, MA, USA
- Department of Genetics, Blavatnik Institute, Harvard Medical School, Boston, MA, USA
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA, USA
| | - Kris Gevaert
- VIB Center for Medical Biotechnology, VIB, Ghent, Belgium
- Department of Biomolecular Medicine, Ghent University, Ghent, Belgium
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4
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Choi M, Kwon H, Pak Y. Caveolin-2 in association with nuclear lamina controls adipocyte hypertrophy. FASEB J 2023; 37:e22745. [PMID: 36637913 DOI: 10.1096/fj.202201028rr] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 12/13/2022] [Accepted: 12/19/2022] [Indexed: 01/14/2023]
Abstract
Here, we identify that Caveolin-2 (Cav-2), an integral membrane protein, controls adipocyte hypertrophy in association with nuclear lamina. In the hypertrophy stage of adipogenesis, pY19-Cav-2 association with lamin A/C facilitated the disengagement of CCAAT/enhancer-binding protein α (C/EBPα) and peroxisome proliferator-activated receptor γ (PPARγ) from lamin A/C and repressed Cav-2 promoter at the nuclear periphery for epigenetic activation of Cav-2, and thereby promoted C/EBPα and PPARγ-induced adipocyte hypertrophy. Stable expression of Cav-2 was required and retained by phosphorylation, deubiquitination, and association with lamin A/C for the adipocyte hypertrophy. However, obese adipocytes exhibited augmented Cav-2 stability resulting from the up-regulation of lamin A/C over lamin B1, protein tyrosine phosphatase 1B (PTP1B), and nuclear deubiquitinating enzyme (DUB), Uchl5. Our findings show a novel epigenetic regulatory mechanism of adipocyte hypertrophy by Cav-2 at the nuclear periphery.
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Affiliation(s)
- Moonjeong Choi
- Division of Life Science, Graduate School of Applied Life Science (BK21 Plus Program), PMBBRC, Gyeongsang National University, Jinju, South Korea
| | - Hayeong Kwon
- Division of Life Science, Graduate School of Applied Life Science (BK21 Plus Program), PMBBRC, Gyeongsang National University, Jinju, South Korea
| | - Yunbae Pak
- Division of Life Science, Graduate School of Applied Life Science (BK21 Plus Program), PMBBRC, Gyeongsang National University, Jinju, South Korea
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5
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Choi M, Kwon H, Jeong K, Pak Y. Epigenetic regulation of Cebpb activation by pY19-Caveolin-2 at the nuclear periphery in association with the nuclear lamina. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2022; 1869:119363. [PMID: 36165916 DOI: 10.1016/j.bbamcr.2022.119363] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Revised: 08/22/2022] [Accepted: 09/11/2022] [Indexed: 06/16/2023]
Abstract
Here, we show that Caveolin-2 (Cav-2) is an epigenetic regulator for adipogenesis. Upon adipogenic stimulation, inner nuclear membrane (INM)-targeted pY19-Cav-2 interacted with lamin A/C to disengage the repressed Cebpb promoter from lamin A/C, which facilitated the Cebpb promoter association with lamin B1. Consequently, pY19-Cav-2 recruited lysine demethylase 4b (KDM4b) for demethylation of histone H3 lysine 9 trimethylation (H3K9me3) and histone acetyltransferase GCN5 for acetylation of H3K27, and subsequently RNA polymerase II (Pol II) on Cebpb promoter for epigenetic activation of Cebpb, to initiate adipogenesis. Cav-2 knock-down abrogated the Cebpb activation and blocked the Pparg2 and Cebpa activation. Re-expression of Cav-2 restored Cebpb activation and adipogenesis in Cav-2-deficient preadipocytes. Our data identify a new mechanism by which the epigenetic activation of Cebpb is controlled at the nuclear periphery to promote adipogenesis.
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Affiliation(s)
- Moonjeong Choi
- Division of Life Science, Graduate School of Applied Life Science (BK21 Plus Program), PMBBRC, Gyeongsang National University, Jinju 52828, Republic of Korea
| | - Hayeong Kwon
- Division of Life Science, Graduate School of Applied Life Science (BK21 Plus Program), PMBBRC, Gyeongsang National University, Jinju 52828, Republic of Korea
| | - Kyuho Jeong
- Department of Biochemistry, College of Medicine, Dongguk University, Gyeongju 38066, Republic of Korea
| | - Yunbae Pak
- Division of Life Science, Graduate School of Applied Life Science (BK21 Plus Program), PMBBRC, Gyeongsang National University, Jinju 52828, Republic of Korea.
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6
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Zhang X, Zhu X, Bi X, Huang J, Zhou L. The Insulin Receptor: An Important Target for the Development of Novel Medicines and Pesticides. Int J Mol Sci 2022; 23:7793. [PMID: 35887136 PMCID: PMC9325136 DOI: 10.3390/ijms23147793] [Citation(s) in RCA: 12] [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: 06/06/2022] [Revised: 07/10/2022] [Accepted: 07/12/2022] [Indexed: 02/04/2023] Open
Abstract
The insulin receptor (IR) is a transmembrane protein that is activated by ligands in insulin signaling pathways. The IR has been considered as a novel therapeutic target for clinical intervention, considering the overexpression of its protein and A-isoform in multiple cancers, Alzheimer's disease, and Type 2 diabetes mellitus in humans. Meanwhile, it may also serve as a potential target in pest management due to its multiple physiological influences in insects. In this review, we provide an overview of the structural and molecular biology of the IR, functions of IRs in humans and insects, physiological and nonpeptide small molecule modulators of the IR, and the regulating mechanisms of the IR. Xenobiotic compounds and the corresponding insecticidal chemicals functioning on the IR are also discussed. This review is expected to provide useful information for a better understanding of human IR-related diseases, as well as to facilitate the development of novel small-molecule activators and inhibitors of the IR for use as medicines or pesticides.
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Affiliation(s)
| | | | | | - Jiguang Huang
- Key Laboratory of Natural Pesticides & Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou 510642, China; (X.Z.); (X.Z.); (X.B.)
| | - Lijuan Zhou
- Key Laboratory of Natural Pesticides & Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou 510642, China; (X.Z.); (X.Z.); (X.B.)
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Cruz SA, Qin Z, Ricke KM, Stewart AFR, Chen HH. Neuronal protein-tyrosine phosphatase 1B hinders sensory-motor functional recovery and causes affective disorders in two different focal ischemic stroke models. Neural Regen Res 2021; 16:129-136. [PMID: 32788467 PMCID: PMC7818877 DOI: 10.4103/1673-5374.286970] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Ischemic brain injury causes neuronal death and inflammation. Inflammation activates protein-tyrosine phosphatase 1B (PTP1B). Here, we tested the significance of PTP1B activation in glutamatergic projection neurons on functional recovery in two models of stroke: by photothrombosis, focal ischemic lesions were induced in the sensorimotor cortex (SM stroke) or in the peri-prefrontal cortex (peri-PFC stroke). Elevated PTP1B expression was detected at 4 days and up to 6 weeks after stroke. While ablation of PTP1B in neurons of neuronal knockout (NKO) mice had no effect on the volume or resorption of ischemic lesions, markedly different effects on functional recovery were observed. SM stroke caused severe sensory and motor deficits (adhesive removal test) in wild type and NKO mice at 4 days, but NKO mice showed drastically improved sensory and motor functional recovery at 8 days. In addition, peri-PFC stroke caused anxiety-like behaviors (elevated plus maze and open field tests), and depression-like behaviors (forced swimming and tail suspension tests) in wild type mice 9 and 28 days after stroke, respectively, with minimal effect on sensory and motor function. Peri-PFC stroke-induced affective disorders were associated with fewer active (FosB+) neurons in the PFC and nucleus accumbens but more FosB+ neurons in the basolateral amygdala, compared to sham-operated mice. In contrast, mice with neuronal ablation of PTP1B were protected from anxiety-like and depression-like behaviors and showed no change in FosB+ neurons after peri-PFC stroke. Taken together, our study identifies neuronal PTP1B as a key component that hinders sensory and motor functional recovery and also contributes to the development of anxiety-like and depression-like behaviors after stroke. Thus, PTP1B may represent a novel therapeutic target to improve stroke recovery. All procedures for animal use were approved by the Animal Care and Use Committee of the University of Ottawa Animal Care and Veterinary Service (protocol 1806) on July 27, 2018.
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Affiliation(s)
- Shelly A Cruz
- Ottawa Hospital Research Institute, Neuroscience Program; Brain and Mind Institute, University of Ottawa, Ottawa, ON, Canada
| | - Zhaohong Qin
- Ottawa Hospital Research Institute, Neuroscience Program; Brain and Mind Institute, University of Ottawa, Ottawa, ON, Canada
| | - Konrad M Ricke
- Brain and Mind Institute; Department of Biochemistry, Microbiology and Immunology, University of Ottawa; University of Ottawa Heart Institute, Ottawa, ON, Canada
| | - Alexandre F R Stewart
- Department of Biochemistry, Microbiology and Immunology; Centre for Infection, Immunity and Inflammation, University of Ottawa; University of Ottawa Heart Institute, Ottawa, ON, Canada
| | - Hsiao-Huei Chen
- Ottawa Hospital Research Institute, Neuroscience Program; Brain and Mind Institute; Cellular and Molecular Medicine; Department of Medicine; Centre for Infection, Immunity and Inflammation, University of Ottawa, Ottawa, ON, Canada
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8
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van Gastel J, Leysen H, Boddaert J, Vangenechten L, Luttrell LM, Martin B, Maudsley S. Aging-related modifications to G protein-coupled receptor signaling diversity. Pharmacol Ther 2020; 223:107793. [PMID: 33316288 DOI: 10.1016/j.pharmthera.2020.107793] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Accepted: 11/26/2020] [Indexed: 02/06/2023]
Abstract
Aging is a highly complex molecular process, affecting nearly all tissue systems in humans and is the highest risk factor in developing neurodegenerative disorders such as Alzheimer's and Parkinson's disease, cardiovascular disease and Type 2 diabetes mellitus. The intense complexity of the aging process creates an incentive to develop more specific drugs that attenuate or even reverse some of the features of premature aging. As our current pharmacopeia is dominated by therapeutics that target members of the G protein-coupled receptor (GPCR) superfamily it may be prudent to search for effective anti-aging therapeutics in this fertile domain. Since the first demonstration of GPCR-based β-arrestin signaling, it has become clear that an enhanced appreciation of GPCR signaling diversity may facilitate the creation of therapeutics with selective signaling activities. Such 'biased' ligand signaling profiles can be effectively investigated using both standard molecular biological techniques as well as high-dimensionality data analyses. Through a more nuanced appreciation of the quantitative nature across the multiple dimensions of signaling bias that drugs possess, researchers may be able to further refine the efficacy of GPCR modulators to impact the complex aberrations that constitute the aging process. Identifying novel effector profiles could expand the effective pharmacopeia and assist in the design of precision medicines. This review discusses potential non-G protein effectors, and specifically their potential therapeutic suitability in aging and age-related disorders.
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Affiliation(s)
- Jaana van Gastel
- Receptor Biology Lab, Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium; Faculty of Pharmacy, Biomedical and Veterinary Science, University of Antwerp, Antwerp, Belgium
| | - Hanne Leysen
- Receptor Biology Lab, Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium; Faculty of Pharmacy, Biomedical and Veterinary Science, University of Antwerp, Antwerp, Belgium
| | - Jan Boddaert
- Molecular Pathology Group, Faculty of Medicine and Health Sciences, Laboratory of Cell Biology and Histology, Antwerp, Belgium
| | - Laura Vangenechten
- Receptor Biology Lab, Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Louis M Luttrell
- Division of Endocrinology, Diabetes & Medical Genetics, Medical University of South Carolina, USA
| | - Bronwen Martin
- Faculty of Pharmacy, Biomedical and Veterinary Science, University of Antwerp, Antwerp, Belgium
| | - Stuart Maudsley
- Receptor Biology Lab, Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium; Faculty of Pharmacy, Biomedical and Veterinary Science, University of Antwerp, Antwerp, Belgium.
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9
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N-myristoylation regulates insulin-induced phosphorylation and ubiquitination of Caveolin-2 for insulin signaling. Biochem Biophys Res Commun 2020; 532:535-540. [PMID: 32896381 DOI: 10.1016/j.bbrc.2020.08.072] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 08/21/2020] [Indexed: 11/22/2022]
Abstract
N-myristoylation is a ubiquitous protein lipidation in eukaryotes, but regulatory roles for myristoylation on proteins still remain to be explored. Here, we show that N-myristoylation of Caveolin-2 (Cav-2) controls insulin signaling. Alternative translation initiation (ATI)-yielded truncated form of non-N-myristoylable Cav-2β and various conditional Cav-2 mutants were compared to full-length form of N-myristoylable Cav-2α. Insulin induced insulin receptor (IR) tyrosine kinase-catalyzed Tyr-19 phosphorylation of N-myristoylable M14A Cav-2 and triggered activation of IR signaling cascade. In contrast, insulin induced ubiquitination of non-N-myristoylable M1A and G2A Cav-2 to facilitate protein-tyrosine phosphatase 1B interaction with IR which desensitized IR signaling through internalization. Metabolic labeling and click chemistry showed palmitoylation of M14A but not M1A and G2A Cav-2. Insulin did not induce phosphorylation of M1A and G2A Cav-2 and Cav-2β. Like Cav-2α, G2A Cav-2 and Cav-2β formed large homo-oligomers localized in lipid rafts. These findings show Cav-2 N-myristoylation plays a crucial role to coordinate its phosphorylation, palmitoylation, and ubiquitination to control insulin signaling.
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Abstract
PURPOSE OF REVIEW Obesity and diabetes have already become the second largest risk factor for cardiovascular disease. During the last decade, remarkable advances have been made in understanding the human genome's contribution to glucose homeostasis disorders and obesity. A few studies on rare mutations of candidate genes provide potential genetic targets for the treatment of diabetes and obesity. In this review, we discussed the detailed findings of these studies and the possible causalities between specific genetic variations and dysfunctions in energy or glucose homeostasis. We are optimistic that novel therapeutic strategies targeting these specific mutants for treating and preventing diabetes and obesity will be developed in the near future. RECENT FINDINGS Studies on rare genetic mutation-caused obesity or diabetes have identified potential genetic targets to decrease body weight or reduce the risk of diabetes. Rare mutations observed in lipodystrophy, obese, or diabetic human patients are promising targets in the treatment of diabetes and obesity.
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Affiliation(s)
- Bing Feng
- Pennington Biomedical Research Center, Brain Glycemic And Metabolism Control Department, Louisiana State University, 6400 Perkins Rd, Basic Science Building L2024, Baton Rouge, LA, 70808, USA
| | - Pingwen Xu
- The Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, The University of Illinois at Chicago, Chicago, IL, 60612, USA
| | - Yanlin He
- Pennington Biomedical Research Center, Brain Glycemic And Metabolism Control Department, Louisiana State University, 6400 Perkins Rd, Basic Science Building L2024, Baton Rouge, LA, 70808, USA.
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11
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The caveolar-mitochondrial interface: regulation of cellular metabolism in physiology and pathophysiology. Biochem Soc Trans 2020; 48:165-177. [PMID: 32010944 DOI: 10.1042/bst20190388] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Revised: 01/09/2020] [Accepted: 01/10/2020] [Indexed: 12/15/2022]
Abstract
The plasma membrane is an important cellular organelle that is often overlooked in terms of a primary factor in regulating physiology and pathophysiology. There is emerging evidence to suggest that the plasma membrane serves a greater purpose than a simple barrier or transporter of ions. New paradigms suggest that the membrane serves as a critical bridge to connect extracellular to intracellular communication particularly to regulate energy and metabolism by forming physical and biochemical associations with intracellular organelles. This review will focus on the relationship of a particular membrane microdomain - caveolae - with mitochondria and the particular implication of this to physiology and pathophysiology.
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12
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Bogaert A, Fernandez E, Gevaert K. N-Terminal Proteoforms in Human Disease. Trends Biochem Sci 2020; 45:308-320. [PMID: 32001092 DOI: 10.1016/j.tibs.2019.12.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 12/06/2019] [Accepted: 12/31/2019] [Indexed: 12/20/2022]
Abstract
The collection of chemically different protein variants, or proteoforms, by far exceeds the number of protein-coding genes in the human genome. Major contributors are alternative splicing and protein modifications. In this review, we focus on those proteoforms that differ at their N termini with a molecular link to disease. We describe the main underlying mechanisms that give rise to such N-terminal proteoforms, these being splicing, initiation of protein translation, and protein modifications. Given their role in several human diseases, it is becoming increasingly clear that several of these N-terminal proteoforms may have potential as therapeutic interventions and/or for diagnosing and prognosing their associated disease.
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Affiliation(s)
- Annelies Bogaert
- VIB Center for Medical Biotechnology, VIB, B-9000 Ghent, Belgium; Department of Biomolecular Medicine, Ghent University, B-9000 Ghent, Belgium
| | - Esperanza Fernandez
- VIB Center for Medical Biotechnology, VIB, B-9000 Ghent, Belgium; Department of Biomolecular Medicine, Ghent University, B-9000 Ghent, Belgium
| | - Kris Gevaert
- VIB Center for Medical Biotechnology, VIB, B-9000 Ghent, Belgium; Department of Biomolecular Medicine, Ghent University, B-9000 Ghent, Belgium.
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13
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Chen Y, Huang L, Qi X, Chen C. Insulin Receptor Trafficking: Consequences for Insulin Sensitivity and Diabetes. Int J Mol Sci 2019; 20:ijms20205007. [PMID: 31658625 PMCID: PMC6834171 DOI: 10.3390/ijms20205007] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Revised: 10/04/2019] [Accepted: 10/08/2019] [Indexed: 12/12/2022] Open
Abstract
Insulin receptor (INSR) has been extensively studied in the area of cell proliferation and energy metabolism. Impaired INSR activities lead to insulin resistance, the key factor in the pathology of metabolic disorders including type 2 diabetes mellitus (T2DM). The mainstream opinion is that insulin resistance begins at a post-receptor level. The role of INSR activities and trafficking in insulin resistance pathogenesis has been largely ignored. Ligand-activated INSR is internalized and trafficked to early endosome (EE), where INSR is dephosphorylated and sorted. INSR can be subsequently conducted to lysosome for degradation or recycled back to the plasma membrane. The metabolic fate of INSR in cellular events implies the profound influence of INSR on insulin signaling pathways. Disruption of INSR-coupled activities has been identified in a wide range of insulin resistance-related diseases such as T2DM. Accumulating evidence suggests that alterations in INSR trafficking may lead to severe insulin resistance. However, there is very little understanding of how altered INSR activities undermine complex signaling pathways to the development of insulin resistance and T2DM. Here, we focus this review on summarizing previous findings on the molecular pathways of INSR trafficking in normal and diseased states. Through this review, we provide insights into the mechanistic role of INSR intracellular processes and activities in the development of insulin resistance and diabetes.
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Affiliation(s)
- Yang Chen
- School of Biomedical Sciences, The University of Queensland, Brisbane 4072, Australia.
| | - Lili Huang
- School of Biomedical Sciences, The University of Queensland, Brisbane 4072, Australia.
| | - Xinzhou Qi
- School of Biomedical Sciences, The University of Queensland, Brisbane 4072, Australia.
| | - Chen Chen
- School of Biomedical Sciences, The University of Queensland, Brisbane 4072, Australia.
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