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Kumar M, Teakel SL, Swarbrick C, Chowdhury IS, Thorn DC, Sunde M, Carver JA, Forwood JK. Amyloid fibril formation, structure and domain swapping of acyl-coenzyme A thioesterase-7. FEBS J 2023; 290:4057-4073. [PMID: 37042241 DOI: 10.1111/febs.16795] [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: 11/14/2022] [Revised: 02/23/2023] [Accepted: 04/11/2023] [Indexed: 04/13/2023]
Abstract
Acyl-coenzyme A thioesterase (Acot) enzymes are involved in a broad range of essential intracellular roles including cell signalling, lipid metabolism, inflammation and the opening of ion channels. Dysregulation in lipid metabolism has been linked to neuroinflammatory and neurological disorders such as Alzheimer's and Parkinson's diseases. Structurally, Acot enzymes adopt a circularised trimeric arrangement with each monomer containing an N- and a C-terminal hotdog domain. Acot7 spontaneously forms amyloid fibrils in vitro under physiological conditions. The resultant amyloid fibrillar structures were characterised by dye-binding fluorescence assays, far-UV circular dichroism spectroscopy, transmission electron microscopy and X-ray fibre diffraction. Acot7 has an unusual mechanism of aggregation with no lag phase. The initial phase (~ 18 h) of aggregation involves conformational rearrangement within the oligomers to form species of enhanced β-sheet character. The subsequent loss of α-helical structure is accompanied by large-scale amyloid fibril formation. The crystal structure of Acot7 revealed an unexpected arrangement of the two domains within the circularised trimeric structure, which is the basis for a proposed mechanism of amyloid fibril formation involving domain swapping during the initial phase of aggregation. Acot7 formed fibrils in the presence of its substrate arachidonoyl-CoA and its inhibitors and maintained its enzyme activity during fibril assembly. It is proposed that the Acot7 fibrillar form acts as functional amyloid.
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Affiliation(s)
- Manjeet Kumar
- Research School of Chemistry, The Australian National University, Acton, Australia
| | - Sarah L Teakel
- School of Dentistry and Medical Science, Charles Sturt University, Wagga Wagga, Australia
| | - Crystall Swarbrick
- School of Dentistry and Medical Science, Charles Sturt University, Wagga Wagga, Australia
| | - Intifar S Chowdhury
- Research School of Chemistry, The Australian National University, Acton, Australia
| | - David C Thorn
- Research School of Chemistry, The Australian National University, Acton, Australia
| | - Margaret Sunde
- School of Medical Sciences, The University of Sydney, Australia
| | - John A Carver
- Research School of Chemistry, The Australian National University, Acton, Australia
| | - Jade K Forwood
- School of Dentistry and Medical Science, Charles Sturt University, Wagga Wagga, Australia
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2
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Zheng C, Zhang G, Xie K, Diao Y, Luo C, Wang Y, Shen Y, Xue Q. Pan-Cancer Analysis and Experimental Validation Identify ACOT7 as a Novel Oncogene and Potential Therapeutic Target in Lung Adenocarcinoma. Cancers (Basel) 2022; 14:cancers14184522. [PMID: 36139682 PMCID: PMC9497106 DOI: 10.3390/cancers14184522] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 09/11/2022] [Accepted: 09/14/2022] [Indexed: 11/16/2022] Open
Abstract
Background: Acyl-CoA thioesterase 7 (ACOT7) is of great significance in regulating cell cycle, cell proliferation, and glucose metabolism. The function of ACOT7 in pan-cancer and its capacity as a prognostic indicator in lung adenocarcinoma (LUAD) remains unknown. We intended to perform a comprehensive pan-cancer analysis of ACOT7 and to validate its value in LUAD. Methods: The expression levels, prognostic significance, molecular function, signaling pathways, and immune infiltration pattern of ACOT7 in 33 cancers were explored via systematic bioinformatics analysis. Multivariate Cox regression was applied to construct nomograms to predict patients’ prognoses. Moreover, we conducted in vitro experiments including CCK8, scratch, Transwell, and Matrigel assays to further explore the function of ACOT7 in LUAD. Results: Patients with high ACOT7 expression have notably poorer long-term survival in many cancer types, including LUAD. Further enrichment analyses reveal that ACOT7 is involved in immune cells’ infiltration and is substantially related to the cancer−immune microenvironment. ACOT7 could influence drug sensitivities, including afatinib, gefitinib, ibrutinib, lapatinib, osimertinib, sapitinib, taselisib, and PLX-4720 (all p < 0.01). A nomogram demonstrated a fair predictive value of ACOT7 in LUAD (C-index: 0.613, 95% CI: 0.568−0.658). The proliferation and migration of PC9 cells were significantly repressed when ACOT7 expression was downregulated. Conclusion: As an oncogene, ACOT7 is critical in the tumor microenvironment of pan-cancer and might be a novel therapeutic target for LUAD.
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Affiliation(s)
- Chao Zheng
- Department of Thoracic Surgery, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China
- Department of Cardiothoracic Surgery, Jinling Hospital, Medical School of Southeast University, Nanjing 210009, China
| | - Guochao Zhang
- Department of Thoracic Surgery, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China
| | - Kai Xie
- Department of Cardiothoracic Surgery, Jinling Hospital, Nanjing Medical University, Nanjing 210009, China
| | - Yifei Diao
- Department of Cardiothoracic Surgery, Jinling Hospital, Medical School of Nanjing University, Nanjing 210009, China
| | - Chao Luo
- Department of Cardiothoracic Surgery, Jinling Hospital, Southern Medical University, Guangzhou 510515, China
| | - Yanqing Wang
- Department of Cardiology, Jinling Hospital, Nanjing University, Nanjing 210009, China
- Correspondence: (Y.W.); (Q.X.)
| | - Yi Shen
- Department of Cardiothoracic Surgery, Jinling Hospital, Medical School of Southeast University, Nanjing 210009, China
| | - Qi Xue
- Department of Thoracic Surgery, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China
- Correspondence: (Y.W.); (Q.X.)
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3
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Xie X, Chen C, Feng S, Zuo S, Zhao X, Li H. Acyl-CoA Thioesterase 7 is Transcriptionally Activated by Krüppel-Like Factor 13 and Promotes the Progression of Hepatocellular Carcinoma. J Hepatocell Carcinoma 2022; 8:1623-1641. [PMID: 34993160 PMCID: PMC8711737 DOI: 10.2147/jhc.s338353] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 12/01/2021] [Indexed: 12/14/2022] Open
Abstract
Purpose Acyl-CoA thioesterase 7(ACOT7) plays an important role in the metabolism of fatty acids. Hepatocellular carcinoma (HCC) has an abnormal lipid profile, and the role of ACOT7 in hepatocellular carcinoma has not been detailedly elucidated. Therefore, we conducted the study to explore the role of ACOT7 in HCC. Materials and Methods The ACOT7 and Krüppel-like factor 13 (KLF13) mRNA expression levels were obtained from The Cancer Genome Atlas (TCGA) database. Bioinformatics analysis identified the underlying upstream regulator of ACOT7. Quantitative real-time PCR was used to detect the expression of mRNA, and immunohistochemical staining and Western blotting were used to detect the expression of protein. Cell Counting Kit-8 and EdU assays were employed to assess the proliferation of HCC cells. Wound-healing and Transwell migration assays were utilized to test the migration ability of HCC cells. Dual-luciferase reporter assay and ChIP assay were used to explore the potential mechanism. Gas chromatography-mass spectrometer was used to analyze the content of free fatty acids. Xenograft tumour growth was used to evaluate the effect of ACOT7 in vivo. Results According to The Cancer Genome Atlas (TCGA) database, ACOT7 mRNA was found to be upregulated and predicted the poor prognosis. Overexpression of ACOT7 enhanced the proliferation, migration and invasion abilities of HCC cells in vitro, as well as the HCC cells proliferation in vivo. Moreover, ACOT7 overexpression increased the yield of the monounsaturated fatty acid Oleic acid (C18:1), which strengthened the proliferation and migration abilities of HCC cells. Mechanistically, KLF13 transcriptionally promoted ACOT7 expression. Further, KLF13 was also overexpressed in HCC tissues and facilitated HCC progression. Conclusion Acyl-CoA thioesterase 7 is transcriptionally activated by Krüppel-like factor 13 and promotes the progression of hepatocellular carcinoma.
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Affiliation(s)
- Xingming Xie
- School of Clinical Medicine, Guizhou Medical University, Guiyang, Guizhou, People's Republic of China.,Department of Hepatobiliary Surgery, The Affiliated Hospital of Guizhou Medical University, Guiyang, Guizhou, People's Republic of China
| | - Chaochun Chen
- School of Clinical Medicine, Guizhou Medical University, Guiyang, Guizhou, People's Republic of China.,Department of Hepatobiliary Surgery, The Affiliated Hospital of Guizhou Medical University, Guiyang, Guizhou, People's Republic of China
| | - Shu Feng
- School of Clinical Medicine, Guizhou Medical University, Guiyang, Guizhou, People's Republic of China.,Department of Infectious Diseases, The Affiliated Hospital of Guizhou Medical University, Guiyang, Guizhou, People's Republic of China
| | - Shi Zuo
- Department of Hepatobiliary Surgery, The Affiliated Hospital of Guizhou Medical University, Guiyang, Guizhou, People's Republic of China
| | - Xueke Zhao
- Department of Infectious Diseases, The Affiliated Hospital of Guizhou Medical University, Guiyang, Guizhou, People's Republic of China
| | - Haiyang Li
- School of Clinical Medicine, Guizhou Medical University, Guiyang, Guizhou, People's Republic of China.,Department of Hepatobiliary Surgery, The Affiliated Hospital of Guizhou Medical University, Guiyang, Guizhou, People's Republic of China
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4
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Feng H, Liu X. Interaction between ACOT7 and LncRNA NMRAL2P via Methylation Regulates Gastric Cancer Progression. Yonsei Med J 2020; 61:471-481. [PMID: 32469171 PMCID: PMC7256001 DOI: 10.3349/ymj.2020.61.6.471] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Revised: 03/13/2020] [Accepted: 04/01/2020] [Indexed: 12/16/2022] Open
Abstract
PURPOSE Gastric cancer (GC) has a very poor prognosis when diagnosed at a late stage. Acyl-CoA thioesterase 7 (ACOT7) is a major isoform of the acyl coenzyme family that catalyzes the hydrolysis of fatty acyl-CoAs into unesterified free fatty acid and coenzyme A. The purpose of this study was to investigate the expression levels of ACOT7 in GC and mechanisms related therewith. MATERIALS AND METHODS Screening of systematic biology studies revealed ACOT7 as a key gene in GC, as well as involvement of the long non-coding RNA NMRAL2P in ACOT7 expression. In this study, GC tissues and adjacent tissue samples were obtained from 10 GC patients at the Department of Gastrointestinal Surgery. GES1 and SGC-7901 cells were collected and treated to silence ACOT7 and overexpress NMRAL2P. The expressions of ACOT7 and NMRAL2P were detected by real-time quantitative PCR and Western blot. Additionally, cell proliferation, apoptosis, migration, and invasion were examined. RESULTS ACOT7 was upregulated in gastric tumor tissues and GC cell lines. ACOT7 gene silencing induced a less malignant phenotype and was closely correlated to reduced cell proliferation and migration, altered cell cycle, and increased apoptosis. Furthermore, NMRAL2P was downregulated in tumor tissues and GC cell lines. NMRAL2P overexpression induced a more malignant phenotype and significantly inhibited the expression of ACOT7. Importantly, NMRAL2P indirectly methylated ACOT7 by binding to DNMT3b, thereby suppressing ACOT7 expression. CONCLUSION NMRAL2P activation suppresses ACOT7 expression in GC. Thus, ACOT7 could be a promising target for the treatment of GC.
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Affiliation(s)
- Huiqin Feng
- Department of Internal Medicine, Tongxiang Chinese Medicine Hospital, Tongxiang, China
| | - Xiaojian Liu
- Department of Surgery, Tongxiang First People's Hospital, Tongxiang, China.
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5
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Bakshi I, Brown SHJ, Brandon AE, Suryana E, Mitchell TW, Turner N, Cooney GJ. Increasing Acyl CoA thioesterase activity alters phospholipid profile without effect on insulin action in skeletal muscle of rats. Sci Rep 2018; 8:13967. [PMID: 30228369 PMCID: PMC6143561 DOI: 10.1038/s41598-018-32354-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Accepted: 05/18/2018] [Indexed: 12/25/2022] Open
Abstract
Increased lipid metabolism in muscle is associated with insulin resistance and therefore, many strategies have been employed to alter fatty acid metabolism and study the impact on insulin action. Metabolism of fatty acid requires activation to fatty acyl CoA by Acyl CoA synthases (ACSL) and fatty acyl CoA can be hydrolysed by Acyl CoA thioesterases (Acot). Thioesterase activity is low in muscle, so we overexpressed Acot7 in muscle of chow and high-fat diet (HFD) rats and investigated effects on insulin action. Acot7 overexpression modified specific phosphatidylcholine and phosphatidylethanolamine species in tibialis muscle of chow rats to levels similar to those observed in control HFD muscle. The changes in phospholipid species did not alter glucose uptake in tibialis muscle under hyperinsulinaemic/euglycaemic clamped conditions. Acot7 overexpression in white extensor digitorum longus (EDL) muscle increased complete fatty acid oxidation ex-vivo but was not associated with any changes in glucose uptake in-vivo, however overexpression of Acot7 in red EDL reduced insulin-stimulated glucose uptake in-vivo which correlated with increased incomplete fatty acid oxidation ex-vivo. In summary, although overexpression of Acot7 in muscle altered some aspects of lipid profile and metabolism in muscle, this had no major effect on insulin-stimulated glucose uptake.
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Affiliation(s)
- Ishita Bakshi
- Diabetes and Metabolism Division, Garvan Institute, Sydney, Australia
| | - Simon H J Brown
- School of Biological Sciences, University of Wollongong, Wollongong, Australia
| | - Amanda E Brandon
- Diabetes and Metabolism Division, Garvan Institute, Sydney, Australia.,Sydney Medical School, Charles Perkins Centre, The University of Sydney, Sydney, Australia
| | - Eurwin Suryana
- Diabetes and Metabolism Division, Garvan Institute, Sydney, Australia
| | - Todd W Mitchell
- School of Biological Sciences, University of Wollongong, Wollongong, Australia
| | - Nigel Turner
- Department of Pharmacology, School of Medical Sciences, UNSW Sydney, Sydney, Australia
| | - Gregory J Cooney
- Diabetes and Metabolism Division, Garvan Institute, Sydney, Australia. .,Sydney Medical School, Charles Perkins Centre, The University of Sydney, Sydney, Australia.
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6
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Tillander V, Alexson SEH, Cohen DE. Deactivating Fatty Acids: Acyl-CoA Thioesterase-Mediated Control of Lipid Metabolism. Trends Endocrinol Metab 2017; 28:473-484. [PMID: 28385385 PMCID: PMC5474144 DOI: 10.1016/j.tem.2017.03.001] [Citation(s) in RCA: 93] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Accepted: 03/01/2017] [Indexed: 12/28/2022]
Abstract
The cellular uptake of free fatty acids (FFA) is followed by esterification to coenzyme A (CoA), generating fatty acyl-CoAs that are substrates for oxidation or incorporation into complex lipids. Acyl-CoA thioesterases (ACOTs) constitute a family of enzymes that hydrolyze fatty acyl-CoAs to form FFA and CoA. Although biochemically and biophysically well characterized, the metabolic functions of these enzymes remain incompletely understood. Existing evidence suggests regulatory roles in controlling rates of peroxisomal and mitochondrial fatty acyl-CoA oxidation, as well as in the subcellular trafficking of fatty acids. Emerging data implicate ACOTs in the pathogenesis of metabolic diseases, suggesting that better understanding their pathobiology could reveal unique targets in the management of obesity, diabetes, and nonalcoholic fatty liver disease.
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Affiliation(s)
- Veronika Tillander
- Division of Clinical Chemistry, Department of Laboratory Medicine, Karolinska Institutet, Karolinska University Hospital, Stockholm, 14186, Sweden
| | - Stefan E H Alexson
- Division of Clinical Chemistry, Department of Laboratory Medicine, Karolinska Institutet, Karolinska University Hospital, Stockholm, 14186, Sweden
| | - David E Cohen
- Division of Gastroenterology and Hepatology, Joan & Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, NY 10021, USA.
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7
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Acyl-CoA thioesterase 7 is involved in cell cycle progression via regulation of PKCζ-p53-p21 signaling pathway. Cell Death Dis 2017; 8:e2793. [PMID: 28518146 PMCID: PMC5584527 DOI: 10.1038/cddis.2017.202] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Revised: 03/14/2017] [Accepted: 04/06/2017] [Indexed: 11/08/2022]
Abstract
Acyl-CoA thioesterase 7 (ACOT7) is a major isoform of the ACOT family that catalyzes hydrolysis of fatty acyl-CoAs to free fatty acids and CoA-SH. However, canonical and non-canonical functions of ACOT7 remain to be discovered. In this study, for the first time, ACOT7 was shown to be responsive to genotoxic stresses such as ionizing radiation (IR) and the anti-cancer drug doxorubicin in time- and dose-dependent manners. ACOT7 knockdown induced cytostasis via activation of the p53-p21 signaling pathway without a DNA damage response. PKCζ was specifically involved in ACOT7 depletion-mediated cell cycle arrest as an upstream molecule of the p53-p21 signaling pathway in MCF7 human breast carcinoma and A549 human lung carcinoma cells. Of the other members of the ACOT family, including ACOT1, 4, 8, 9, 11, 12, and 13 that were expressed in human, ACOT4, 8, and 12 were responsive to genotoxic stresses. However, none of those had a role in cytostasis via activation of the PKCζ-p53-p21 signaling pathway. Analysis of the ACOT7 prognostic value revealed that low ACOT7 levels prolonged overall survival periods in breast and lung cancer patients. Furthermore, ACOT7 mRNA levels were higher in lung cancer patient tissues compared to normal tissues. We also observed a synergistic effect of ACOT7 depletion in combination with either IR or doxorubicin on cell proliferation in breast and lung cancer cells. Together, our data suggest that a low level of ACOT7 may be involved, at least in part, in the prevention of human breast and lung cancer development via regulation of cell cycle progression.
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8
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Wall VZ, Barnhart S, Kramer F, Kanter JE, Vivekanandan-Giri A, Pennathur S, Bolego C, Ellis JM, Gijón MA, Wolfgang MJ, Bornfeldt KE. Inflammatory stimuli induce acyl-CoA thioesterase 7 and remodeling of phospholipids containing unsaturated long (≥C20)-acyl chains in macrophages. J Lipid Res 2017; 58:1174-1185. [PMID: 28416579 DOI: 10.1194/jlr.m076489] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Indexed: 01/01/2023] Open
Abstract
Acyl-CoA thioesterase 7 (ACOT7) is an intracellular enzyme that converts acyl-CoAs to FFAs. ACOT7 is induced by lipopolysaccharide (LPS); thus, we investigated downstream effects of LPS-induced induction of ACOT7 and its role in inflammatory settings in myeloid cells. Enzymatic thioesterase activity assays in WT and ACOT7-deficient macrophage lysates indicated that endogenous ACOT7 contributes a significant fraction of total acyl-CoA thioesterase activity toward C20:4-, C20:5-, and C22:6-CoA, but contributes little activity toward shorter acyl-CoA species. Lipidomic analyses revealed that LPS causes a dramatic increase, primarily in bis(monoacylglycero)phosphate species containing long (≥C20) polyunsaturated acyl-chains in macrophages, and that the limited effect observed by ACOT7 deficiency is restricted to glycerophospholipids containing 20-carbon unsaturated acyl-chains. Furthermore, ACOT7 deficiency did not detectably alter the ability of LPS to induce cytokines or prostaglandin E2 production in macrophages. Consistently, although ACOT7 was induced in macrophages from diabetic mice, hematopoietic ACOT7 deficiency did not alter the stimulatory effect of diabetes on systemic inflammation or atherosclerosis in LDL receptor-deficient mice. Thus, inflammatory stimuli induce ACOT7 and remodeling of phospholipids containing unsaturated long (≥C20)-acyl chains in macrophages, and, although ACOT7 has preferential thioesterase activity toward these lipid species, loss of ACOT7 has no major detrimental effect on macrophage inflammatory phenotypes.≥.
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Affiliation(s)
- Valerie Z Wall
- Department of Medicine, UW Medicine Diabetes Institute, University of Washington, Seattle, WA.,Division of Metabolism, Endocrinology and Nutrition, and Department of Pathology, UW Medicine Diabetes Institute, University of Washington, Seattle, WA
| | - Shelley Barnhart
- Department of Medicine, UW Medicine Diabetes Institute, University of Washington, Seattle, WA
| | - Farah Kramer
- Department of Medicine, UW Medicine Diabetes Institute, University of Washington, Seattle, WA
| | - Jenny E Kanter
- Department of Medicine, UW Medicine Diabetes Institute, University of Washington, Seattle, WA
| | | | | | - Chiara Bolego
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Padova, Italy
| | - Jessica M Ellis
- Department of Nutrition Science, Purdue University, West Lafayette, IN.,Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Miguel A Gijón
- Department of Pharmacology, University of Colorado Denver, Aurora, CO
| | - Michael J Wolfgang
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Karin E Bornfeldt
- Department of Medicine, UW Medicine Diabetes Institute, University of Washington, Seattle, WA .,Division of Metabolism, Endocrinology and Nutrition, and Department of Pathology, UW Medicine Diabetes Institute, University of Washington, Seattle, WA
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9
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Martinez-Sanchez A, Pullen TJ, Chabosseau P, Zhang Q, Haythorne E, Cane MC, Nguyen-Tu MS, Sayers SR, Rutter GA. Disallowance of Acot7 in β-Cells Is Required for Normal Glucose Tolerance and Insulin Secretion. Diabetes 2016; 65:1268-82. [PMID: 26861785 PMCID: PMC6101210 DOI: 10.2337/db15-1240] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Accepted: 02/04/2016] [Indexed: 12/18/2022]
Abstract
Encoding acyl-CoA thioesterase-7 (Acot7) is one of ∼60 genes expressed ubiquitously across tissues but relatively silenced, or disallowed, in pancreatic β-cells. The capacity of ACOT7 to hydrolyze long-chain acyl-CoA esters suggests potential roles in β-oxidation, lipid biosynthesis, signal transduction, or insulin exocytosis. We explored the physiological relevance of β-cell-specific Acot7 silencing by re-expressing ACOT7 in these cells. ACOT7 overexpression in clonal MIN6 and INS1(832/13) β-cells impaired insulin secretion in response to glucose plus fatty acids. Furthermore, in a panel of transgenic mouse lines, we demonstrate that overexpression of mitochondrial ACOT7 selectively in the adult β-cell reduces glucose tolerance dose dependently and impairs glucose-stimulated insulin secretion. By contrast, depolarization-induced secretion was unaffected, arguing against a direct action on the exocytotic machinery. Acyl-CoA levels, ATP/ADP increases, membrane depolarization, and Ca(2+) fluxes were all markedly reduced in transgenic mouse islets, whereas glucose-induced oxygen consumption was unchanged. Although glucose-induced increases in ATP/ADP ratio were similarly lowered after ACOT7 overexpression in INS1(832/13) cells, changes in mitochondrial membrane potential were unaffected, consistent with an action of Acot7 to increase cellular ATP consumption. Because Acot7 mRNA levels are increased in human islets in type 2 diabetes, inhibition of the enzyme might provide a novel therapeutic strategy.
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Affiliation(s)
- Aida Martinez-Sanchez
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Imperial Centre for Translational and Experimental Medicine, Imperial College London, London, U.K
| | - Timothy J Pullen
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Imperial Centre for Translational and Experimental Medicine, Imperial College London, London, U.K
| | - Pauline Chabosseau
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Imperial Centre for Translational and Experimental Medicine, Imperial College London, London, U.K
| | | | - Elizabeth Haythorne
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Imperial Centre for Translational and Experimental Medicine, Imperial College London, London, U.K
| | - Matthew C Cane
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Imperial Centre for Translational and Experimental Medicine, Imperial College London, London, U.K
| | - Marie-Sophie Nguyen-Tu
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Imperial Centre for Translational and Experimental Medicine, Imperial College London, London, U.K
| | - Sophie R Sayers
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Imperial Centre for Translational and Experimental Medicine, Imperial College London, London, U.K
| | - Guy A Rutter
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Imperial Centre for Translational and Experimental Medicine, Imperial College London, London, U.K.
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10
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Ellis JM, Bowman CE, Wolfgang MJ. Metabolic and tissue-specific regulation of acyl-CoA metabolism. PLoS One 2015; 10:e0116587. [PMID: 25760036 PMCID: PMC4356623 DOI: 10.1371/journal.pone.0116587] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Accepted: 12/11/2014] [Indexed: 01/22/2023] Open
Abstract
Acyl-CoA formation initiates cellular fatty acid metabolism. Acyl-CoAs are generated by the ligation of a fatty acid to Coenzyme A mediated by a large family of acyl-CoA synthetases (ACS). Conversely, acyl-CoAs can be hydrolyzed by a family of acyl-CoA thioesterases (ACOT). Here, we have determined the transcriptional regulation of all ACS and ACOT enzymes across tissues and in response to metabolic perturbations. We find patterns of coordinated regulation within and between these gene families as well as distinct regulation occurring in a tissue- and physiologically-dependent manner. Due to observed changes in long-chain ACOT mRNA and protein abundance in liver and adipose tissue, we determined the consequence of increasing cytosolic long-chain thioesterase activity on fatty acid metabolism in these tissues by generating transgenic mice overexpressing a hyperactive mutant of Acot7 in the liver or adipose tissue. Doubling cytosolic acyl-CoA thioesterase activity failed to protect mice from diet-induced obesity, fatty liver or insulin resistance, however, overexpression of Acot7 in adipocytes rendered mice cold intolerant. Together, these data suggest distinct modes of regulation of the ACS and ACOT enzymes and that these enzymes act in a coordinated fashion to control fatty acid metabolism in a tissue-dependent manner.
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Affiliation(s)
- Jessica M. Ellis
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Center for Metabolism and Obesity Research, Baltimore, Maryland 21205 United States of America
| | - Caitlyn E. Bowman
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Center for Metabolism and Obesity Research, Baltimore, Maryland 21205 United States of America
| | - Michael J. Wolfgang
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Center for Metabolism and Obesity Research, Baltimore, Maryland 21205 United States of America
- * E-mail:
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11
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Asadollahi R, Oneda B, Joset P, Azzarello-Burri S, Bartholdi D, Steindl K, Vincent M, Cobilanschi J, Sticht H, Baldinger R, Reissmann R, Sudholt I, Thiel CT, Ekici AB, Reis A, Bijlsma EK, Andrieux J, Dieux A, FitzPatrick D, Ritter S, Baumer A, Latal B, Plecko B, Jenni OG, Rauch A. The clinical significance of small copy number variants in neurodevelopmental disorders. J Med Genet 2014; 51:677-88. [PMID: 25106414 PMCID: PMC4173859 DOI: 10.1136/jmedgenet-2014-102588] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
BACKGROUND Despite abundant evidence for pathogenicity of large copy number variants (CNVs) in neurodevelopmental disorders (NDDs), the individual significance of genome-wide rare CNVs <500 kb has not been well elucidated in a clinical context. METHODS By high-resolution chromosomal microarray analysis, we investigated the clinical significance of all rare non-polymorphic exonic CNVs sizing 1-500 kb in a cohort of 714 patients with undiagnosed NDDs. RESULTS We detected 96 rare CNVs <500 kb affecting coding regions, of which 58 (60.4%) were confirmed. 6 of 14 confirmed de novo, one of two homozygous and four heterozygous inherited CNVs affected the known microdeletion regions 17q21.31, 16p11.2 and 2p21 or OMIM morbid genes (CASK, CREBBP, PAFAH1B1, SATB2; AUTS2, NRXN3, GRM8). Two further de novo CNVs affecting single genes (MED13L, CTNND2) were instrumental in delineating novel recurrent conditions. For the first time, we here report exonic deletions of CTNND2 causing low normal IQ with learning difficulties with or without autism spectrum disorder. Additionally, we discovered a homozygous out-of-frame deletion of ACOT7 associated with features comparable to the published mouse model. In total, 24.1% of the confirmed small CNVs were categorised as pathogenic or likely pathogenic (median size 130 kb), 17.2% as likely benign, 3.4% represented incidental findings and 55.2% remained unclear. CONCLUSIONS These results verify the diagnostic relevance of genome-wide rare CNVs <500 kb, which were found pathogenic in ∼2% (14/714) of cases (1.1% de novo, 0.3% homozygous, 0.6% inherited) and highlight their inherent potential for discovery of new conditions.
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Affiliation(s)
- Reza Asadollahi
- Institute of Medical Genetics, University of Zurich, Schlieren-Zurich, Switzerland
| | - Beatrice Oneda
- Institute of Medical Genetics, University of Zurich, Schlieren-Zurich, Switzerland
| | - Pascal Joset
- Institute of Medical Genetics, University of Zurich, Schlieren-Zurich, Switzerland
| | | | - Deborah Bartholdi
- Institute of Medical Genetics, University of Zurich, Schlieren-Zurich, Switzerland
| | - Katharina Steindl
- Institute of Medical Genetics, University of Zurich, Schlieren-Zurich, Switzerland
| | - Marie Vincent
- Institute of Medical Genetics, University of Zurich, Schlieren-Zurich, Switzerland
| | - Joana Cobilanschi
- Institute of Medical Genetics, University of Zurich, Schlieren-Zurich, Switzerland
| | - Heinrich Sticht
- Institute of Biochemistry, University of Erlangen-Nuremberg, Erlangen, Germany
| | - Rosa Baldinger
- Institute of Medical Genetics, University of Zurich, Schlieren-Zurich, Switzerland
| | - Regina Reissmann
- Institute of Medical Genetics, University of Zurich, Schlieren-Zurich, Switzerland
| | - Irene Sudholt
- Institute of Medical Genetics, University of Zurich, Schlieren-Zurich, Switzerland
| | - Christian T Thiel
- Institute of Human Genetics, University of Erlangen-Nuremberg, Erlangen, Germany
| | - Arif B Ekici
- Institute of Human Genetics, University of Erlangen-Nuremberg, Erlangen, Germany
| | - André Reis
- Institute of Human Genetics, University of Erlangen-Nuremberg, Erlangen, Germany
| | - Emilia K Bijlsma
- Department of Clinical Genetics, Leiden University Medical Center (LUMC), Leiden, The Netherlands
| | - Joris Andrieux
- Institut de Génétique Médicale, Hôpital Jeanne de Flandre, CHRU de Lille, Lille, France
| | - Anne Dieux
- Clinique de Génétique Guy Fontaine, Hôpital Jeanne de Flandre, CHRU de Lille, Lille, France
| | - David FitzPatrick
- MRC Human Genetics Unit, MRC Institute for Genetic and Molecular Medicine, University of Edinburgh, Edinburgh, UK
| | - Susanne Ritter
- Child Development Center, University Children's Hospital Zurich, Zurich, Switzerland
| | - Alessandra Baumer
- Institute of Medical Genetics, University of Zurich, Schlieren-Zurich, Switzerland
| | - Beatrice Latal
- Child Development Center, University Children's Hospital Zurich, Zurich, Switzerland
| | - Barbara Plecko
- Division of Child Neurology, University Children's Hospital Zurich, Zurich, Switzerland
| | - Oskar G Jenni
- Child Development Center, University Children's Hospital Zurich, Zurich, Switzerland
| | - Anita Rauch
- Institute of Medical Genetics, University of Zurich, Schlieren-Zurich, Switzerland
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Tillander V, Arvidsson Nordström E, Reilly J, Strozyk M, Van Veldhoven PP, Hunt MC, Alexson SEH. Acyl-CoA thioesterase 9 (ACOT9) in mouse may provide a novel link between fatty acid and amino acid metabolism in mitochondria. Cell Mol Life Sci 2014; 71:933-48. [PMID: 23864032 PMCID: PMC11114068 DOI: 10.1007/s00018-013-1422-1] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2013] [Revised: 06/13/2013] [Accepted: 07/04/2013] [Indexed: 02/03/2023]
Abstract
Acyl-CoA thioesterase (ACOT) activities are found in prokaryotes and in several compartments of eukaryotes where they hydrolyze a wide range of acyl-CoA substrates and thereby regulate intracellular acyl-CoA/CoA/fatty acid levels. ACOT9 is a mitochondrial ACOT with homologous genes found from bacteria to humans and in this study we have carried out an in-depth kinetic characterization of ACOT9 to determine its possible physiological function. ACOT9 showed unusual kinetic properties with activity peaks for short-, medium-, and saturated long-chain acyl-CoAs with highest V max with propionyl-CoA and (iso) butyryl-CoA while K cat/K m was highest with saturated long-chain acyl-CoAs. Further characterization of the short-chain acyl-CoA activity revealed that ACOT9 also hydrolyzes a number of short-chain acyl-CoAs and short-chain methyl-branched CoA esters that suggest a role for ACOT9 in regulation also of amino acid metabolism. In spite of markedly different K ms, ACOT9 can hydrolyze both short- and long-chain acyl-CoAs simultaneously, indicating that ACOT9 may provide a novel regulatory link between fatty acid and amino acid metabolism in mitochondria. Based on similar acyl-CoA chain-length specificities of recombinant ACOT9 and ACOT activity in mouse brown adipose tissue and kidney mitochondria, we conclude that ACOT9 is the major mitochondrial ACOT hydrolyzing saturated C2-C20-CoA in these tissues. Finally, ACOT9 activity is strongly regulated by NADH and CoA, suggesting that mitochondrial metabolic state regulates the function of ACOT9.
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Affiliation(s)
- Veronika Tillander
- Department of Laboratory Medicine, Division of Clinical Chemistry, Karolinska Institutet, C1-74, Karolinska University Hospital, SE-141 86 Stockholm, Sweden
| | - Elisabet Arvidsson Nordström
- Department of Laboratory Medicine, Division of Clinical Chemistry, Karolinska Institutet, C1-74, Karolinska University Hospital, SE-141 86 Stockholm, Sweden
| | - Jenny Reilly
- Department of Laboratory Medicine, Division of Clinical Chemistry, Karolinska Institutet, C1-74, Karolinska University Hospital, SE-141 86 Stockholm, Sweden
| | - Malgorzata Strozyk
- Department of Laboratory Medicine, Division of Clinical Chemistry, Karolinska Institutet, C1-74, Karolinska University Hospital, SE-141 86 Stockholm, Sweden
| | - Paul P. Van Veldhoven
- Department of Cellular and Molecular Medicine, LIPIT, Campus Gasthuisberg, Katholieke Universiteit Leuven, Herestraat, Leuven, Belgium
| | - Mary C. Hunt
- Dublin Institute of Technology, School of Biological Sciences, Kevin Street, Dublin 8, Ireland
| | - Stefan E. H. Alexson
- Department of Laboratory Medicine, Division of Clinical Chemistry, Karolinska Institutet, C1-74, Karolinska University Hospital, SE-141 86 Stockholm, Sweden
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13
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Acyl coenzyme A thioesterase 7 regulates neuronal fatty acid metabolism to prevent neurotoxicity. Mol Cell Biol 2013; 33:1869-82. [PMID: 23459938 DOI: 10.1128/mcb.01548-12] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Numerous neurological diseases are associated with dysregulated lipid metabolism; however, the basic metabolic control of fatty acid metabolism in neurons remains enigmatic. Here we have shown that neurons have abundant expression and activity of the long-chain cytoplasmic acyl coenzyme A (acyl-CoA) thioesterase 7 (ACOT7) to regulate lipid retention and metabolism. Unbiased and targeted metabolomic analysis of fasted mice with a conditional knockout of ACOT7 in the nervous system, Acot7(N-/-), revealed increased fatty acid flux into multiple long-chain acyl-CoA-dependent pathways. The alterations in brain fatty acid metabolism were concomitant with a loss of lean mass, hypermetabolism, hepatic steatosis, dyslipidemia, and behavioral hyperexcitability in Acot7(N-/-) mice. These failures in adaptive energy metabolism are common in neurodegenerative diseases. In agreement, Acot7(N-/-) mice exhibit neurological dysfunction and neurodegeneration. These data show that ACOT7 counterregulates fatty acid metabolism in neurons and protects against neurotoxicity.
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14
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Fujita M, Momose A, Ohtomo T, Nishinosono A, Tanonaka K, Toyoda H, Morikawa M, Yamada J. Upregulation of fatty acyl-CoA thioesterases in the heart and skeletal muscle of rats fed a high-fat diet. Biol Pharm Bull 2011; 34:87-91. [PMID: 21212523 DOI: 10.1248/bpb.34.87] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In rodent models of diet-induced obesity, prolonged high-fat feeding increases the cellular uptake of fatty acids and causes lipotoxicity in the heart and skeletal muscle, where substrate overload to beta-oxidation generates mitochondrial stress. We examined the hypothesis that, because of its catalytic properties, acyl-CoA thioesterase (ACOT) would counteract these detrimental situations by modulating intracellular acyl-CoA levels. Rats were fed a low- or high-fat diet for up to 20 weeks, and the expressions of ACOT isoforms and fatty acid beta-oxidation enzymes were analyzed by western blotting. The expressions of ACOT1, ACOT2 and ACOT7 proteins in the heart and soleus muscle were significantly increased, by 2.0-7.6-fold, in rats fed the high-fat diet as compared with the low-fat diet group. These effects were accompanied by increases in carnitine palmitoyltransferase and acyl-CoA oxidase expression. However, ACOT was not induced in the extensor digitorum longus muscle or the liver. Subcellular fractionation of heart and soleus muscle homogenates confirmed expression of both the cytosolic and mitochondrial ACOT isoforms. These results underscore the functional relationship between ACOT and fatty acid oxidation, and suggest adaptive upregulation of ACOT to protect against fatty acid oversupply in the heart and skeletal muscle.
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Affiliation(s)
- Mariko Fujita
- Department of Clinical Biochemistry, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, Hachioji, Tokyo 192–0392, Japan
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15
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Hermo L, Pelletier RM, Cyr DG, Smith CE. Surfing the wave, cycle, life history, and genes/proteins expressed by testicular germ cells. Part 4: intercellular bridges, mitochondria, nuclear envelope, apoptosis, ubiquitination, membrane/voltage-gated channels, methylation/acetylation, and transcription factors. Microsc Res Tech 2010; 73:364-408. [PMID: 19941288 DOI: 10.1002/jemt.20785] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
As germ cells divide and differentiate from spermatogonia to spermatozoa, they share a number of structural and functional features that are common to all generations of germ cells and these features are discussed herein. Germ cells are linked to one another by large intercellular bridges which serve to move molecules and even large organelles from the cytoplasm of one cell to another. Mitochondria take on different shapes and features and topographical arrangements to accommodate their specific needs during spermatogenesis. The nuclear envelope and pore complex also undergo extensive modifications concomitant with the development of germ cell generations. Apoptosis is an event that is normally triggered by germ cells and involves many proteins. It occurs to limit the germ cell pool and acts as a quality control mechanism. The ubiquitin pathway comprises enzymes that ubiquitinate as well as deubiquitinate target proteins and this pathway is present and functional in germ cells. Germ cells express many proteins involved in water balance and pH control as well as voltage-gated ion channel movement. In the nucleus, proteins undergo epigenetic modifications which include methylation, acetylation, and phosphorylation, with each of these modifications signaling changes in chromatin structure. Germ cells contain specialized transcription complexes that coordinate the differentiation program of spermatogenesis, and there are many male germ cell-specific differences in the components of this machinery. All of the above features of germ cells will be discussed along with the specific proteins/genes and abnormalities to fertility related to each topic.
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Affiliation(s)
- Louis Hermo
- Department of Anatomy and Cell Biology, Faculty of Medicine, McGill University, 3640 University Street, Montreal, QC Canada H3A 2B2.
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16
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Kirkby B, Roman N, Kobe B, Kellie S, Forwood JK. Functional and structural properties of mammalian acyl-coenzyme A thioesterases. Prog Lipid Res 2010; 49:366-77. [PMID: 20470824 DOI: 10.1016/j.plipres.2010.04.001] [Citation(s) in RCA: 109] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2010] [Revised: 04/23/2010] [Accepted: 04/26/2010] [Indexed: 10/19/2022]
Abstract
Acyl-coenzyme A thioesterases (Acots) play important cellular roles in mammalian fatty acid metabolism through modulation of cellular concentrations of activated fatty acyl-CoAs. Acots catalyse the hydrolysis of the thioester bond present within acyl-CoA ester molecules to yield coenzyme A (CoASH) and the corresponding non-esterified fatty acid. Acyl-CoA thioesterases are expressed ubiquitously in both prokaryotes and eukaryotes and, in higher order organisms, the enzymes are expressed and localised in a tissue-dependent manner within the cytosol, mitochondria, peroxisomes and endoplasmic reticulum. Recent studies have led to advances in the functional and structural characterization of many mammalian Acot family members. These include the structure determination of both type-I and type-II Acot family members, structural elucidation of the START domain of ACOT11, identification of roles in arachidonic acid and inflammatory prostaglandin production by Acot7, and inclusion of a 13th Acot family member. Here, we review and analyse the current literature on mammalian Acots with respect to their characterization and summarize the current knowledge on the structure, function and regulation of this enzyme family.
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Affiliation(s)
- Brenda Kirkby
- School of Biomedical Sciences, Charles Sturt University, Wagga Wagga, NSW 2650, Australia
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17
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Shubina DM, Suchkova IO, Slominskaya NA, Alenina N, Bader M, Patkin EL. CENTB5 gene expression in humans and mice. Mol Biol 2009. [DOI: 10.1134/s0026893309030042] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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18
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Abstract
In this review we will evaluate evidence that altered gene dosage and structure impacts neurodevelopment and neural connectivity through deleterious effects on synaptic structure and function, and evidence that the latter are key contributors to the risk for autism. We will review information on alterations of structure of mitochondrial DNA and abnormal mitochondrial function in autism and indications that interactions of the nuclear and mitochondrial genomes may play a role in autism pathogenesis. In a final section we will present data derived using Affymetrix SNP 6.0 microarray analysis of DNA of a number of subjects and parents recruited to our autism spectrum disorders project. We include data on two sets of monozygotic twins. Collectively these data provide additional evidence of nuclear and mitochondrial genome imbalance in autism and evidence of specific candidate genes in autism. We present data on dosage changes in genes that map on the X chromosomes and the Y chromosome. Precise analyses of Y located genes are often difficult because of the high degree of homology of X- and Y-related genes. However, continued efforts to analyze the latter are important, given the consistent evidence for a 4:1 ratio of males to females affected by autism. It is also important to consider whether environmental factors play a role in generating the nuclear and mitochondrial genomic instability we have observed. The study of autism will benefit from a move to analysis of pathways and multigene clusters for identification of subtypes that share a specific genetic etiology.
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Affiliation(s)
- Moyra Smith
- Department of Pediatrics, University of California-Irvine, Irvine, CA 92697, USA.
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