101
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Xu C, Bai B, Fan P, Cai Y, Huang B, Law IKM, Liu L, Xu A, Tung C, Li X, Siu FM, Che CM, Vanhoutte PM, Wang Y. Selective overexpression of human SIRT1 in adipose tissue enhances energy homeostasis and prevents the deterioration of insulin sensitivity with ageing in mice. Am J Transl Res 2013; 5:412-426. [PMID: 23724165 PMCID: PMC3665915] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2013] [Accepted: 05/21/2013] [Indexed: 06/02/2023]
Abstract
SIRT1, a longevity regulator and NAD(+)-dependent deacetylase, plays a critical role in promoting metabolic fitness associated with calorie restriction and healthy ageing. Using a tissue-specific transgenic approach, the present study demonstrates that over-expression of human SIRT1 selectively in adipose tissue of mice prevents ageing-induced deterioration of insulin sensitivity and ectopic lipid distribution, reduces whole body fat mass and enhances locomotor activity. During ageing, the water-soluble vitamin biotin is progressively accumulated in adipose tissue. Over-expression of SIRT1 alleviates ageing-associated biotin accumulation and reduces the amount of biotinylated proteins, including acetyl CoA carboxylase, a major reservoir of biotin in adipose tissues. Chronic biotin supplementation increases adipose biotin contents and abolishes adipose SIRT1-mediated beneficial effects on insulin sensitivity, lipid metabolism and locomotor activity. Biochemical, spectrometric and chromatographic analysis revealed that biotin and its metabolites act as competitive inhibitors of SIRT1-mediated deacetylation. In summary, these results demonstrate that adipose SIRT1 is a key player in maintaining systemic energy homeostasis and insulin sensitivity; enhancing its activity solely in adipose tissue can prevent ageing-associated metabolic disorders.
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Affiliation(s)
- Cheng Xu
- Department of Pharmacology and Pharmacy, The University of Hong KongHong Kong, China
| | - Bo Bai
- Department of Pharmacology and Pharmacy, The University of Hong KongHong Kong, China
| | - Pengcheng Fan
- Department of Pharmacology and Pharmacy, The University of Hong KongHong Kong, China
| | - Yu Cai
- Department of Pharmacology and Pharmacy, The University of Hong KongHong Kong, China
| | - Bosheng Huang
- Department of Pharmacology and Pharmacy, The University of Hong KongHong Kong, China
| | - Ivy KM Law
- Department of Pharmacology and Pharmacy, The University of Hong KongHong Kong, China
| | - Ling Liu
- Department of Pharmacology and Pharmacy, The University of Hong KongHong Kong, China
| | - Aimin Xu
- Department of Pharmacology and Pharmacy, The University of Hong KongHong Kong, China
| | - Chunling Tung
- Department of Chemistry and Open Laboratory of Chemical Biology of the Institute of Molecular Technology for Drug Discovery and Synthesis, The University of Hong KongHong Kong, China
| | - Xuechen Li
- Department of Chemistry and Open Laboratory of Chemical Biology of the Institute of Molecular Technology for Drug Discovery and Synthesis, The University of Hong KongHong Kong, China
| | - Fung-Ming Siu
- Department of Chemistry and Open Laboratory of Chemical Biology of the Institute of Molecular Technology for Drug Discovery and Synthesis, The University of Hong KongHong Kong, China
| | - Chi-Ming Che
- Department of Chemistry and Open Laboratory of Chemical Biology of the Institute of Molecular Technology for Drug Discovery and Synthesis, The University of Hong KongHong Kong, China
| | - Paul M Vanhoutte
- Department of Pharmacology and Pharmacy, The University of Hong KongHong Kong, China
| | - Yu Wang
- Department of Pharmacology and Pharmacy, The University of Hong KongHong Kong, China
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102
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Zu X, Zhong J, Luo D, Tan J, Zhang Q, Wu Y, Liu J, Cao R, Wen G, Cao D. Chemical genetics of acetyl-CoA carboxylases. Molecules 2013; 18:1704-19. [PMID: 23358327 PMCID: PMC6269866 DOI: 10.3390/molecules18021704] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2012] [Revised: 01/03/2013] [Accepted: 01/11/2013] [Indexed: 12/16/2022] Open
Abstract
Chemical genetic studies on acetyl-CoA carboxylases (ACCs), rate-limiting enzymes in long chain fatty acid biosynthesis, have greatly advanced the understanding of their biochemistry and molecular biology and promoted the use of ACCs as targets for herbicides in agriculture and for development of drugs for diabetes, obesity and cancers. In mammals, ACCs have both biotin carboxylase (BC) and carboxyltransferase (CT) activity, catalyzing carboxylation of acetyl-CoA to malonyl-CoA. Several classes of small chemicals modulate ACC activity, including cellular metabolites, natural compounds, and chemically synthesized products. This article reviews chemical genetic studies of ACCs and the use of ACCs for targeted therapy of cancers.
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Affiliation(s)
- Xuyu Zu
- Institute of Clinical Medicine, the First Affiliated Hospital, University of South China, Hengyang 421001, Hunan, China
| | - Jing Zhong
- Institute of Clinical Medicine, the First Affiliated Hospital, University of South China, Hengyang 421001, Hunan, China
| | - Dixian Luo
- Institute of Translational Medicine & Department of Laboratory Medicine, the First People’s Hospital of Chenzhou, 102 Luojiajing Road, Chenzhou 423000, Hunan, China
| | - Jingjing Tan
- Institute of Clinical Medicine, the First Affiliated Hospital, University of South China, Hengyang 421001, Hunan, China
| | - Qinghai Zhang
- Institute of Clinical Medicine, the First Affiliated Hospital, University of South China, Hengyang 421001, Hunan, China
| | - Ying Wu
- Institute of Clinical Medicine, the First Affiliated Hospital, University of South China, Hengyang 421001, Hunan, China
| | - Jianghua Liu
- Institute of Clinical Medicine, the First Affiliated Hospital, University of South China, Hengyang 421001, Hunan, China
| | - Renxian Cao
- Institute of Clinical Medicine, the First Affiliated Hospital, University of South China, Hengyang 421001, Hunan, China
- Authors to whom correspondence should be addressed; E-Mails: (R.C.); (D.C.); Tel.: +86-217-545-9703 (D.C.); Fax: +86-217-545-9718 (D.C.)
| | - Gebo Wen
- Institute of Clinical Medicine, the First Affiliated Hospital, University of South China, Hengyang 421001, Hunan, China
| | - Deliang Cao
- Department of Microbiology, Immunology and Cell Biology, Simmons Cancer Institute, Southern Illinois University School of Medicine, 913 N. Rutledge Street, Springfield, IL 62794, USA
- Authors to whom correspondence should be addressed; E-Mails: (R.C.); (D.C.); Tel.: +86-217-545-9703 (D.C.); Fax: +86-217-545-9718 (D.C.)
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103
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Mislocalization and inhibition of acetyl-CoA carboxylase 1 by a synthetic small molecule. Biochem J 2013; 448:409-16. [PMID: 23067267 DOI: 10.1042/bj20121158] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Chromeceptin is a synthetic small molecule that inhibits insulin-induced adipogenesis of 3T3-L1 cells and impairs the function of IGF2 (insulin-like growth factor 2). The molecular target of this benzochromene derivative is MFP-2 (multifunctional protein 2). The interaction between chromeceptin and MFP-2 activates STAT6 (signal transducer and activator of transcription 6), which subsequently induces IGF inhibitory genes. It was not previously known how the binding of chromeceptin with MFP-2 blocks adipogenesis and activates STAT6. The results of the present study show that the chromeceptin-MFP-2 complex binds to and inhibits ACC1 (acetyl-CoA carboxylase 1), an enzyme important for the de novo synthesis of malonyl-CoA and fatty acids. The formation of this ternary complex removes ACC1 from the cytosol and sequesters it in peroxisomes under the guidance of Pex5p (peroxisomal-targeting signal type 1 receptor). As a result, chromeceptin impairs fatty acid synthesis from acetate where ACC1 is a rate-limiting enzyme. Overexpression of malonyl-CoA decarboxylase or siRNA (small interfering RNA) knockdown of ACC1 results in STAT6 activation, suggesting a role for malonyl-CoA in STAT6 signalling. The molecular mechanism of chromeceptin may provide a new pharmacological approach to selective inhibition of ACC1 for biological studies and pharmaceutical development.
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104
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1 0 6. Cancer Biomark 2012. [DOI: 10.1201/b14318-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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105
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Huard K, Bagley SW, Menhaji-Klotz E, Préville C, Southers JA, Smith AC, Edmonds DJ, Lucas JC, Dunn MF, Allanson NM, Blaney EL, Garcia-Irizarry CN, Kohrt JT, Griffith DA, Dow RL. Synthesis of Spiropiperidine Lactam Acetyl-CoA Carboxylase Inhibitors. J Org Chem 2012; 77:10050-7. [DOI: 10.1021/jo3014808] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Kim Huard
- Pfizer Worldwide Research & Development, Eastern Point Road, Groton, Connecticut 06340, United States
| | - Scott W. Bagley
- Pfizer Worldwide Research & Development, Eastern Point Road, Groton, Connecticut 06340, United States
| | - Elnaz Menhaji-Klotz
- Pfizer Worldwide Research & Development, Eastern Point Road, Groton, Connecticut 06340, United States
| | - Cathy Préville
- Pfizer Worldwide Research & Development, Eastern Point Road, Groton, Connecticut 06340, United States
| | - James A. Southers
- Pfizer Worldwide Research & Development, Eastern Point Road, Groton, Connecticut 06340, United States
| | - Aaron C. Smith
- Pfizer Worldwide Research & Development, Eastern Point Road, Groton, Connecticut 06340, United States
| | - David J. Edmonds
- Pfizer Worldwide Research & Development, Eastern Point Road, Groton, Connecticut 06340, United States
| | - John C. Lucas
- Pfizer Worldwide Research & Development, Eastern Point Road, Groton, Connecticut 06340, United States
| | - Matthew F. Dunn
- Pfizer Worldwide Research & Development, Eastern Point Road, Groton, Connecticut 06340, United States
| | - Nigel M. Allanson
- Peakdale Molecular Ltd, Peakdale Science Park, Sheffield Road, Chapel-en-le-Frith,
High Peak, SK23 0PG, United Kingdom
| | - Emma L. Blaney
- Peakdale Molecular Ltd, Peakdale Science Park, Sheffield Road, Chapel-en-le-Frith,
High Peak, SK23 0PG, United Kingdom
| | - Carmen N. Garcia-Irizarry
- Pfizer Worldwide Research & Development, Eastern Point Road, Groton, Connecticut 06340, United States
| | - Jeffrey T. Kohrt
- Pfizer Worldwide Research & Development, Eastern Point Road, Groton, Connecticut 06340, United States
| | - David A. Griffith
- Pfizer Worldwide Research & Development, Eastern Point Road, Groton, Connecticut 06340, United States
| | - Robert L. Dow
- Pfizer Worldwide Research & Development, Eastern Point Road, Groton, Connecticut 06340, United States
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106
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Park JA, Tirupathi Pichiah P, Yu JJ, Oh SH, Daily J, Cha YS. Anti-obesity effect of kimchi fermented with Weissella koreensis
OK1-6 as starter in high-fat diet-induced obese C57BL/6J mice. J Appl Microbiol 2012; 113:1507-16. [DOI: 10.1111/jam.12017] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2012] [Revised: 09/08/2012] [Accepted: 09/09/2012] [Indexed: 12/01/2022]
Affiliation(s)
- J.-A. Park
- Department of Food Science and Human Nutrition; Chonbuk National University; Jeonju Korea
| | - P.B. Tirupathi Pichiah
- Department of Food Science and Human Nutrition; Chonbuk National University; Jeonju Korea
| | - J.-J. Yu
- Department of Food Science and Biotechnology; Woosuk University; Jeonju Korea
| | - S.-H. Oh
- Department of Food Science and Biotechnology; Woosuk University; Jeonju Korea
| | - J.W. Daily
- Department of Research and Development; Daily Manufacturing, Inc.; Rockwell NC, USA
| | - Y.-S. Cha
- Department of Food Science and Human Nutrition; Chonbuk National University; Jeonju Korea
- Jeonju Makgeolli Research Center; Chonbuk National University; Jeonju Korea
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107
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Kuo DH, Hung MC, Hung CM, Liu LM, Chen FA, Shieh PC, Ho CT, Way TD. Body weight management effect of burdock (Arctium lappa L.) root is associated with the activation of AMP-activated protein kinase in human HepG2 cells. Food Chem 2012; 134:1320-6. [DOI: 10.1016/j.foodchem.2012.03.023] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2011] [Revised: 02/29/2012] [Accepted: 03/06/2012] [Indexed: 11/16/2022]
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108
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Vigueira PA, Ray SS, Martin BA, Ligon MM, Paul KS. Effects of the green tea catechin (-)-epigallocatechin gallate on Trypanosoma brucei. INTERNATIONAL JOURNAL FOR PARASITOLOGY-DRUGS AND DRUG RESISTANCE 2012; 2:225-9. [PMID: 24533284 DOI: 10.1016/j.ijpddr.2012.09.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2012] [Revised: 09/11/2012] [Accepted: 09/13/2012] [Indexed: 12/11/2022]
Abstract
The current pharmacopeia to treat the lethal human and animal diseases caused by the protozoan parasite Trypanosoma brucei remains limited. The parasite's ability to undergo antigenic variation represents a considerable barrier to vaccine development, making the identification of new drug targets extremely important. Recent studies have demonstrated that fatty acid synthesis is important for growth and virulence of Trypanosoma brucei brucei, suggesting this pathway may have therapeutic potential. The first committed step of fatty acid synthesis is catalyzed by acetyl-CoA carboxylase (ACC), which is a known target of (-)-epigallocatechin-3-gallate (EGCG), an active polyphenol compound found in green tea. EGCG exerts its effects on ACC through activation of AMP-dependent protein kinase, which phosphorylates and inhibits ACC. We found that EGCG inhibited TbACC activity with an EC50 of 37 μM and 55 μM for bloodstream form and procyclic form lysates, respectively. Treatment with 100 μM EGCG induced a 4.7- and 1.7- fold increase in TbACC phosphorylation in bloodstream form and procyclic lysates. EGCG also inhibited the growth of bloodstream and procyclic parasites in culture, with a 48 h EC50 of 33 μM and 27 μM, respectively, which is greater than the EGCG plasma levels typically achievable in humans through oral dosing. Daily intraperitoneal administration of EGCG did not reduce the virulence of an acute mouse model of T. b. brucei infection. These data suggest a reduced potential for EGCG to treat T. brucei infections, but suggest that EGCG may prove to be useful as a tool to probe ACC regulation.
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Affiliation(s)
- Patrick A Vigueira
- Department of Biological Sciences, Clemson University, Clemson, SC 29634, USA
| | - Sunayan S Ray
- Department of Genetics & Biochemistry, Clemson University, Clemson, SC 29634, USA
| | - Ben A Martin
- Department of Biological Sciences, Clemson University, Clemson, SC 29634, USA
| | - Marianne M Ligon
- Department of Genetics & Biochemistry, Clemson University, Clemson, SC 29634, USA
| | - Kimberly S Paul
- Department of Genetics & Biochemistry, Clemson University, Clemson, SC 29634, USA
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109
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Structure and function of biotin-dependent carboxylases. Cell Mol Life Sci 2012; 70:863-91. [PMID: 22869039 DOI: 10.1007/s00018-012-1096-0] [Citation(s) in RCA: 258] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2012] [Revised: 07/07/2012] [Accepted: 07/09/2012] [Indexed: 12/14/2022]
Abstract
Biotin-dependent carboxylases include acetyl-CoA carboxylase (ACC), propionyl-CoA carboxylase (PCC), 3-methylcrotonyl-CoA carboxylase (MCC), geranyl-CoA carboxylase, pyruvate carboxylase (PC), and urea carboxylase (UC). They contain biotin carboxylase (BC), carboxyltransferase (CT), and biotin-carboxyl carrier protein components. These enzymes are widely distributed in nature and have important functions in fatty acid metabolism, amino acid metabolism, carbohydrate metabolism, polyketide biosynthesis, urea utilization, and other cellular processes. ACCs are also attractive targets for drug discovery against type 2 diabetes, obesity, cancer, microbial infections, and other diseases, and the plastid ACC of grasses is the target of action of three classes of commercial herbicides. Deficiencies in the activities of PCC, MCC, or PC are linked to serious diseases in humans. Our understanding of these enzymes has been greatly enhanced over the past few years by the crystal structures of the holoenzymes of PCC, MCC, PC, and UC. The structures reveal unanticipated features in the architectures of the holoenzymes, including the presence of previously unrecognized domains, and provide a molecular basis for understanding their catalytic mechanism as well as the large collection of disease-causing mutations in PCC, MCC, and PC. This review will summarize the recent advances in our knowledge on the structure and function of these important metabolic enzymes.
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110
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Galdieri L, Vancura A. Acetyl-CoA carboxylase regulates global histone acetylation. J Biol Chem 2012; 287:23865-76. [PMID: 22580297 PMCID: PMC3390662 DOI: 10.1074/jbc.m112.380519] [Citation(s) in RCA: 148] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2012] [Indexed: 12/15/2022] Open
Abstract
Histone acetylation depends on intermediary metabolism for supplying acetyl-CoA in the nucleocytosolic compartment. However, because nucleocytosolic acetyl-CoA is also used for de novo synthesis of fatty acids, histone acetylation and synthesis of fatty acids compete for the same acetyl-CoA pool. The first and rate-limiting reaction in de novo synthesis of fatty acids is carboxylation of acetyl-CoA to form malonyl-CoA, catalyzed by acetyl-CoA carboxylase. In yeast Saccharomyces cerevisiae, acetyl-CoA carboxylase is encoded by the ACC1 gene. In this study, we show that attenuated expression of ACC1 results in increased acetylation of bulk histones, globally increased acetylation of chromatin histones, and altered transcriptional regulation. Together, our data indicate that Acc1p activity regulates the availability of acetyl-CoA for histone acetyltransferases, thus representing a link between intermediary metabolism and epigenetic mechanisms of transcriptional regulation.
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Affiliation(s)
- Luciano Galdieri
- From the Department of Biological Sciences, St. John's University, Queens, New York 11439
| | - Ales Vancura
- From the Department of Biological Sciences, St. John's University, Queens, New York 11439
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111
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Li W, Tai Y, Zhou J, Gu W, Bai Z, Zhou T, Zhong Z, McCue PA, Sang N, Ji JY, Kong B, Jiang J, Wang C. Repression of endometrial tumor growth by targeting SREBP1 and lipogenesis. Cell Cycle 2012; 11:2348-58. [PMID: 22672904 DOI: 10.4161/cc.20811] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The aberrantly increased lipogenesis is a universal metabolic feature of proliferating tumor cells. Although most normal cells acquire the bulk of their fatty acids from circulation, tumor cells synthesize more than 90% of required lipids de novo. The sterol regulatory element-binding protein 1 (SREBP1), encoded by SREBF1 gene, is a master regulator of lipogenic gene expression. SREBP1 and its target genes are overexpressed in a variety of cancers; however, the role of SREBP1 in endometrial cancer is largely unknown. We have screened a cohort of endometrial cancer (EC) specimen for their lipogenic gene expression and observed a significant increase of SREBP1 target gene expression in cancer cells compared with normal endometrium. By using immunohistochemical staining, we confirmed SREBP1 protein overexpression and demonstrated increased nuclear distribution of SREBP1 in EC. In addition, we found that knockdown of SREBP1 expression in EC cells suppressed cell growth, reduced colonigenic capacity and slowed tumor growth in vivo. Furthermore, we observed that knockdown of SREBP1 induced significant cell death in cultured EC cells. Taken together, our results show that SREBP1 is essential for EC cell growth both in vitro and in vivo, suggesting that SREBP1 activity may be a novel therapeutic target for endometrial cancers.
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Affiliation(s)
- Weihua Li
- Department of Obstetrics and Gynecology, Qilu Hospital, Shandong University, Jinan, Shandong, China
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112
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Barbosa-Cabrera E, Salas-Casas A, Rojas-Hernández S, Jarillo-Luna A, Abarca-Rojano E, Rodríguez MA, Campos-Rodríguez R. Purification and cellular localization of the Entamoeba histolytica transcarboxylase. Parasitol Res 2012; 111:1401-5. [PMID: 22453500 DOI: 10.1007/s00436-012-2898-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2011] [Accepted: 03/14/2012] [Indexed: 11/26/2022]
Abstract
Genome analysis of Entamoeba histolytica predicts the presence of acetyl-CoA carboxylase. Using Western blot, histochemistry, and confocal microscopy, we demonstrated the presence of a biotin-containing protein in the cytoplasm of E. histolytica, with a molecular weight of 136 kDa and biotin-carboxylase activity. This protein probably corresponds to a transcarboxylase that catalyzes the rate-limiting reaction leading to fatty acid elongation.
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Affiliation(s)
- E Barbosa-Cabrera
- Sección de Estudios de Posgrado e Investigación, Escuela Superior de Medicina, Instituto Politécnico Nacional, Plan de San Luís y Díaz Mirón, CP 11340, Mexico, D.F., Mexico
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113
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Vigueira PA, Paul KS. Trypanosoma brucei: inhibition of acetyl-CoA carboxylase by haloxyfop. Exp Parasitol 2011; 130:159-65. [PMID: 22119241 DOI: 10.1016/j.exppara.2011.10.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2011] [Revised: 10/08/2011] [Accepted: 10/31/2011] [Indexed: 10/15/2022]
Abstract
Trypanosoma brucei, a eukaryotic pathogen that causes African sleeping sickness in humans and nagana in cattle, depends on the enzyme acetyl-CoA carboxylase (ACC) for full virulence in mice. ACC produces malonyl-CoA, the two carbon donor for fatty acid synthesis. We assessed the effect of haloxyfop, an aryloxyphenoxypropionate herbicide inhibitor of plastid ACCs in many plants as well as Toxoplasma gondii, on T. brucei ACC activity and growth in culture. Haloxyfop inhibited TbACC in cell lysate (EC(50) 67 μM), despite the presence of an amino acid motif typically associated with resistance. Haloxyfop also reduced growth of bloodstream and procyclic form parasites (EC(50) of 0.8 and 1.2 mM). However, the effect on growth was likely due to off-target effects because haloxyfop treatment had no effect on fatty acid elongation or incorporation into complex lipids in vivo.
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Affiliation(s)
- Patrick A Vigueira
- Department of Biological Sciences, Clemson University, Clemson, SC 29634, USA.
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114
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Uncovering genomic causes of co-morbidity in epilepsy: gene-driven phenotypic characterization of rare microdeletions. PLoS One 2011; 6:e23182. [PMID: 21858020 PMCID: PMC3157359 DOI: 10.1371/journal.pone.0023182] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2011] [Accepted: 07/07/2011] [Indexed: 12/13/2022] Open
Abstract
Background Patients with epilepsy often suffer from other important conditions. The existence of such co-morbidities is frequently not recognized and their relationship with epilepsy usually remains unexplained. Methodology/Principal Findings We describe three patients with common, sporadic, non-syndromic epilepsies in whom large genomic microdeletions were found during a study of genetic susceptibility to epilepsy. We performed detailed gene-driven clinical investigations in each patient. Disruption of the function of genes in the deleted regions can explain co-morbidities in these patients. Conclusions/Significance Co-morbidities in patients with epilepsy can be part of a genomic abnormality even in the absence of (known) congenital malformations or intellectual disabilities. Gene-driven phenotype examination can also reveal clinically significant unsuspected condition.
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115
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Affiliation(s)
- Hanley N Abramson
- Department of Pharmaceutical Sciences, Eugene Applebaum College of Pharmacy and Health Sciences, Wayne State University, 259 Mack Avenue, Detroit, Michigan 48201, USA.
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116
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Wu J, Ji F, DI W, Chen H, Wan Y. Activation of acetyl-coenzyme A carboxylase is involved in Taxol-induced ovarian cancer cell death. Oncol Lett 2011; 2:543-547. [PMID: 22866118 DOI: 10.3892/ol.2011.286] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2010] [Accepted: 03/09/2011] [Indexed: 11/05/2022] Open
Abstract
Acetyl-coenzyme A carboxylase (ACC) is an attractive target for research into the treatment of a variety of human diseases, including diabetes, obesity and cancer. Mounting evidence suggests that the inhibition of ACC induced of cancer cell apoptosis. However, whether the inhibition of ACC regulates apoptosis in CaOV3 cancer cells has yet to be addressed. This study investigated the cytotoxic mechanism of action of ACC inhibition. Results showed that 5-(tetradecyloxy)-2-furoic acid (TOFA), an ACC inhibitor, enhanced Taxol-induced CaOV3 human ovarian cancer cell apoptosis. Notably, when TOFA was administered as a monotherapy, it induced CaOV3 cell apoptosis. Pre-treatment with the EGFR inhibitor PD153035 was found to markedly enhance ACC phosphorylation, whereas AMP-activated protein kinase (AMPK) activator AICAR was found to marginally enhance ACC phosphorylation. Taken together, the data showed ACC is a potential novel molecular target of Taxol. Additionally, ACC inhibition partially contributed to the cytotoxic effect of Taxol in ovarian cancer cells.
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Affiliation(s)
- Jiang Wu
- Department of Dermatology, China Medical University, Shenyang, Liaoning 110001
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117
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Targeting thermogenesis and related pathways in anti-obesity drug discovery. Pharmacol Ther 2011; 131:295-308. [PMID: 21514319 DOI: 10.1016/j.pharmthera.2011.04.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2011] [Accepted: 03/29/2011] [Indexed: 01/12/2023]
Abstract
The health consequences of the obesity epidemic are a huge burden on patients and society. Yet it remains an unmet therapeutic need. Lifestyle or behaviour modification, although desirable, seems to benefit only a few and bariatric surgery is not an option for all and not without risks. Nevertheless, bariatric surgery is currently the gold standard in terms of weight loss therapy and any weight loss agent will be in combination with management of lifestyle modification. Sadly, there is a poor history for the pharmacological treatment of obesity and repeated safety concerns have attracted intense regulatory scrutiny. Indeed, recent market withdrawals leave us with just one agent approved for the long term treatment of obesity and that is only mildly efficacious in terms of weight loss, although it is beneficial in terms of metabolic health. There are two broad pharmacological approaches that can be applied in obesity drug discovery: reduce intake (or absorption) or increase expenditure (thermogenesis) of calories. In this review we will look at the latter approach. We will cover regulatory requirements and the rationale for this approach. We believe that post-obese subjects display abnormal metabolic responses to weight loss that almost inevitably leads to weight regain. We will then explore a number of approaches that potentially increase thermogenesis in humans. The challenge we have is in accumulating enough human data to validate this approach using drugs.
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Bengtsson C, Blaho S, Saitton DB, Brickmann K, Broddefalk J, Davidsson O, Drmota T, Folmer R, Hallberg K, Hallén S, Hovland R, Isin E, Johannesson P, Kull B, Larsson LO, Löfgren L, Nilsson KE, Noeske T, Oakes N, Plowright AT, Schnecke V, Ståhlberg P, Sörme P, Wan H, Wellner E, Oster L. Design of small molecule inhibitors of acetyl-CoA carboxylase 1 and 2 showing reduction of hepatic malonyl-CoA levels in vivo in obese Zucker rats. Bioorg Med Chem 2011; 19:3039-53. [PMID: 21515056 DOI: 10.1016/j.bmc.2011.04.014] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2011] [Revised: 04/06/2011] [Accepted: 04/09/2011] [Indexed: 01/09/2023]
Abstract
Inhibition of acetyl-CoA carboxylases has the potential for modulating long chain fatty acid biosynthesis and mitochondrial fatty acid oxidation. Hybridization of weak inhibitors of ACC2 provided a novel, moderately potent but lipophilic series. Optimization led to compounds 33 and 37, which exhibit potent inhibition of human ACC2, 10-fold selectivity over inhibition of human ACC1, good physical and in vitro ADME properties and good bioavailability. X-ray crystallography has shown this series binding in the CT-domain of ACC2 and revealed two key hydrogen bonding interactions. Both 33 and 37 lower levels of hepatic malonyl-CoA in vivo in obese Zucker rats.
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119
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A spectrophotometric assay for measuring acetyl–coenzyme A carboxylase. Anal Biochem 2011; 411:100-5. [DOI: 10.1016/j.ab.2010.11.046] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2010] [Revised: 11/24/2010] [Accepted: 11/30/2010] [Indexed: 01/11/2023]
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120
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Gago G, Diacovich L, Arabolaza A, Tsai SC, Gramajo H. Fatty acid biosynthesis in actinomycetes. FEMS Microbiol Rev 2011; 35:475-97. [PMID: 21204864 DOI: 10.1111/j.1574-6976.2010.00259.x] [Citation(s) in RCA: 116] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
All organisms that produce fatty acids do so via a repeated cycle of reactions. In mammals and other animals, these reactions are catalyzed by a type I fatty acid synthase (FAS), a large multifunctional protein to which the growing chain is covalently attached. In contrast, most bacteria (and plants) contain a type II system in which each reaction is catalyzed by a discrete protein. The pathway of fatty acid biosynthesis in Escherichia coli is well established and has provided a foundation for elucidating the type II FAS pathways in other bacteria (White et al., 2005). However, fatty acid biosynthesis is more diverse in the phylum Actinobacteria: Mycobacterium, possess both FAS systems while Streptomyces species have only the multienzyme FAS II system and Corynebacterium species exclusively FAS I. In this review, we present an overview of the genome organization, biochemical properties and physiological relevance of the two FAS systems in the three genera of actinomycetes mentioned above. We also address in detail the biochemical and structural properties of the acyl-CoA carboxylases (ACCases) that catalyzes the first committed step of fatty acid synthesis in actinomycetes, and discuss the molecular bases of their substrate specificity and the structure-based identification of new ACCase inhibitors with antimycobacterial properties.
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Affiliation(s)
- Gabriela Gago
- Microbiology Division, IBR (Instituto de Biología Molecular y Celular de Rosario), Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina
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121
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Jump DB, Torres-Gonzalez M, Olson LK. Soraphen A, an inhibitor of acetyl CoA carboxylase activity, interferes with fatty acid elongation. Biochem Pharmacol 2010; 81:649-60. [PMID: 21184748 DOI: 10.1016/j.bcp.2010.12.014] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2010] [Revised: 12/08/2010] [Accepted: 12/10/2010] [Indexed: 02/06/2023]
Abstract
Acetyl CoA carboxylase (ACC1 and ACC2) generates malonyl CoA, a substrate for de novo lipogenesis (DNL) and an inhibitor of mitochondrial fatty acid β-oxidation (FAO). Malonyl CoA is also a substrate for microsomal fatty acid elongation, an important pathway for saturated (SFA), mono- (MUFA) and polyunsaturated fatty acid (PUFA) synthesis. Despite the interest in ACC as a target for obesity and cancer therapy, little attention has been given to the role ACC plays in long chain fatty acid synthesis. This report examines the effect of pharmacological inhibition of ACC on DNL and palmitate (16:0) and linoleate (18:2, n-6) metabolism in HepG2 and LnCap cells. The ACC inhibitor, soraphen A, lowers cellular malonyl CoA, attenuates DNL and the formation of fatty acid elongation products derived from exogenous fatty acids, i.e., 16:0 and 18:2, n-6; IC(50)∼5nM. Elevated expression of fatty acid elongases (Elovl5, Elovl6) or desaturases (FADS1, FADS2) failed to override the soraphen A effect on SFA, MUFA or PUFA synthesis. Inhibition of fatty acid elongation leads to the accumulation of 16- and 18-carbon unsaturated fatty acids derived from 16:0 and 18:2, n-6, respectively. Pharmacological inhibition of ACC activity will not only attenuate DNL and induce FAO, but will also attenuate the synthesis of very long chain saturated, mono- and polyunsaturated fatty acids.
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Affiliation(s)
- Donald B Jump
- Department of Nutrition and Exercise Sciences, The Linus Pauling Institute, Oregon State University, Corvallis, OR 97331, United States.
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122
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Mechanism for the inhibition of the carboxyltransferase domain of acetyl-coenzyme A carboxylase by pinoxaden. Proc Natl Acad Sci U S A 2010; 107:22072-7. [PMID: 21135213 DOI: 10.1073/pnas.1012039107] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Acetyl-CoA carboxylases (ACCs) are crucial metabolic enzymes and have been targeted for drug development against obesity, diabetes, and other diseases. The carboxyltransferase (CT) domain of this enzyme is the site of action for three different classes of herbicides, as represented by haloxyfop, tepraloxydim, and pinoxaden. Our earlier studies have demonstrated that haloxyfop and tepraloxydim bind in the CT active site at the interface of its dimer. However, the two compounds probe distinct regions of the dimer interface, sharing primarily only two common anchoring points of interaction with the enzyme. We report here the crystal structure of the CT domain of yeast ACC in complex with pinoxaden at 2.8-Å resolution. Despite their chemical diversity, pinoxaden has a similar binding mode as tepraloxydim and requires a small conformational change in the dimer interface for binding. Crystal structures of the CT domain in complex with all three classes of herbicides confirm the importance of the two anchoring points for herbicide binding. The structures also provide a foundation for understanding the molecular basis of the herbicide resistance mutations and cross resistance among the herbicides, as well as for the design and development of new inhibitors against plant and human ACCs.
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123
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Lee AK, Kyriakou T, Weston AJ, O'Dell SD. Functional Single-Nucleotide Polymorphism in Acetyl-CoA Carboxylase ACACB Gene Promoter. DNA Cell Biol 2010; 29:703-12. [DOI: 10.1089/dna.2010.1078] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Alex K. Lee
- Nutritional Sciences Division, King's College London, London, United Kingdom
| | - Theodosios Kyriakou
- Nutritional Sciences Division, King's College London, London, United Kingdom
| | - Andrew J. Weston
- NIHR Biomedical Research Centre for Mental Health, King's College London Proteomics Facility, Institute of Psychiatry, London, United Kingdom
| | - Sandra D. O'Dell
- Nutritional Sciences Division, King's College London, London, United Kingdom
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124
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Keil S, Müller M, Zoller G, Haschke G, Schroeter K, Glien M, Ruf S, Focken I, Herling AW, Schmoll D. Identification and synthesis of novel inhibitors of acetyl-CoA carboxylase with in vitro and in vivo efficacy on fat oxidation. J Med Chem 2010; 53:8679-87. [PMID: 21082864 DOI: 10.1021/jm101179e] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Acetyl CoA carboxylase isoforms 1 and 2 (ACC1/2) are key enzymes of fat utilization and their inhibition is considered to improve aspects of the metabolic syndrome. To identify pharmacological inhibitors of ACC1/2, a high throughput screen was performed which resulted in the identification of the lead compound 3 ( Gargazanli , G. ; Lardenois , P. ; Frost , J. ; George , P. Patent WO9855474 A1, 1998 ) as a moderate selective ACC2 inhibitor. Optimization of 3 led to 4m ( Zoller , G. ; Schmoll , D. ; Mueller , M. ; Haschke , G. ; Focken , I. Patent WO2010003624 A2, 2010 ) as a submicromolar dual ACC1/2 inhibitor of the rat and human isoforms. 4m possessed favorable pharmacokinetic parameters. This compound stimulated fat oxidation in vivo and reduced plasma triglyceride levels in a rodent model after subchronic administration. 4m is a suitable tool compound for the elucidation of the pharmacological potential of ACC1/2 inhibition.
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Affiliation(s)
- Stefanie Keil
- Sanofi-Aventis Deutschland GmbH, R&D, Diabetes Division, Industriepark Hoechst, Building G 878, D-65926 Frankfurt am Main, Germany.
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125
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Arabolaza A, Shillito ME, Lin TW, Diacovich L, Melgar M, Pham H, Amick D, Gramajo H, Tsai SC. Crystal structures and mutational analyses of acyl-CoA carboxylase beta subunit of Streptomyces coelicolor. Biochemistry 2010; 49:7367-76. [PMID: 20690600 DOI: 10.1021/bi1005305] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The first committed step of fatty acid and polyketides biosynthesis, the biotin-dependent carboxylation of an acyl-CoA, is catalyzed by acyl-CoA carboxylases (ACCases) such as acetyl-CoA carboxylase (ACC) and propionyl-CoA carboxylase (PCC). ACC and PCC in Streptomyces coelicolor are homologue multisubunit complexes that can carboxylate different short chain acyl-CoAs. While ACC is able to carboxylate acetyl-, propionyl-, or butyryl-CoA with approximately the same specificity, PCC only recognizes propionyl- and butyryl-CoA as substrates. How ACC and PCC have such different specificities toward these substrates is only partially understood. To further understand the molecular basis of how the active site residues can modulate the substrate recognition, we mutated D422, N80, R456, and R457 of PccB, the catalytic beta subunit of PCC. The crystal structures of six PccB mutants and the wild type crystal structure were compared systematically to establish the sequence-structure-function relationship that correlates the observed substrate specificity toward acetyl-, propionyl-, and butyryl-CoA with active site geometry. The experimental data confirmed that D422 is a key determinant of substrate specificity, influencing not only the active site properties but further altering protein stability and causing long-range conformational changes. Mutations of N80, R456, and R457 lead to variations in the quaternary structure of the beta subunit and to a concomitant loss of enzyme activity, indicating the importance of these residues in maintaining the active protein conformation as well as a critical role in substrate binding.
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Affiliation(s)
- Ana Arabolaza
- Instituto de Biología Molecular y Celular de Rosario (IBR-Consejo Nacional de Investigaciones Científicas y Técnicas) and Departamento de Microbiología, Facultad de Ciencias Bioquímicasy Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, 2000 Rosario, Argentina
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126
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Recombinant yeast screen for new inhibitors of human acetyl-CoA carboxylase 2 identifies potential drugs to treat obesity. Proc Natl Acad Sci U S A 2010; 107:9093-8. [PMID: 20439761 DOI: 10.1073/pnas.1003721107] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Acetyl-CoA carboxylase (ACC) is a key enzyme of fatty acid metabolism with multiple isozymes often expressed in different eukaryotic cellular compartments. ACC-made malonyl-CoA serves as a precursor for fatty acids; it also regulates fatty acid oxidation and feeding behavior in animals. ACC provides an important target for new drugs to treat human diseases. We have developed an inexpensive nonradioactive high-throughput screening system to identify new ACC inhibitors. The screen uses yeast gene-replacement strains depending for growth on cloned human ACC1 and ACC2. In "proof of concept" experiments, growth of such strains was inhibited by compounds known to target human ACCs. The screen is sensitive and robust. Medium-size chemical libraries yielded new specific inhibitors of human ACC2. The target of the best of these inhibitors was confirmed with in vitro enzymatic assays. This compound is a new drug chemotype inhibiting human ACC2 with 2.8 muM IC(50) and having no effect on human ACC1 at 100 muM.
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127
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Plaimas K, Eils R, König R. Identifying essential genes in bacterial metabolic networks with machine learning methods. BMC SYSTEMS BIOLOGY 2010; 4:56. [PMID: 20438628 PMCID: PMC2874528 DOI: 10.1186/1752-0509-4-56] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/17/2009] [Accepted: 05/03/2010] [Indexed: 01/05/2023]
Abstract
Background Identifying essential genes in bacteria supports to identify potential drug targets and an understanding of minimal requirements for a synthetic cell. However, experimentally assaying the essentiality of their coding genes is resource intensive and not feasible for all bacterial organisms, in particular if they are infective. Results We developed a machine learning technique to identify essential genes using the experimental data of genome-wide knock-out screens from one bacterial organism to infer essential genes of another related bacterial organism. We used a broad variety of topological features, sequence characteristics and co-expression properties potentially associated with essentiality, such as flux deviations, centrality, codon frequencies of the sequences, co-regulation and phyletic retention. An organism-wise cross-validation on bacterial species yielded reliable results with good accuracies (area under the receiver-operator-curve of 75% - 81%). Finally, it was applied to drug target predictions for Salmonella typhimurium. We compared our predictions to the viability of experimental knock-outs of S. typhimurium and identified 35 enzymes, which are highly relevant to be considered as potential drug targets. Specifically, we detected promising drug targets in the non-mevalonate pathway. Conclusions Using elaborated features characterizing network topology, sequence information and microarray data enables to predict essential genes from a bacterial reference organism to a related query organism without any knowledge about the essentiality of genes of the query organism. In general, such a method is beneficial for inferring drug targets when experimental data about genome-wide knockout screens is not available for the investigated organism.
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Affiliation(s)
- Kitiporn Plaimas
- Department of Bioinformatics and Functional Genomics, Institute of Pharmacy and Molecular Biotechnology, Bioquant, University of Heidelberg, Im Neuenheimer Feld 267, 69120 Heidelberg, Germany
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128
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Gene knockout of Acc2 has little effect on body weight, fat mass, or food intake. Proc Natl Acad Sci U S A 2010; 107:7598-603. [PMID: 20368432 DOI: 10.1073/pnas.0913492107] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Deletion of acetyl CoA carboxylase-2 (Acc2) reportedly causes leanness in the setting of hyperphagia. To determine the cellular basis for these effects, we generated a mouse model in which Acc2 can be selectively deleted by the action of Cre recombinase. Deletion of Acc2 from skeletal muscle, the predominant site of Acc2 expression, had no effect on body weight, food intake, or body composition. When Acc2 was inactivated in the germline, Acc2 knockout (Acc2KO) mice displayed no differences in body weight, food intake, body composition, or glucose homeostasis as compared to controls on chow or high fat diet. Total malonyl CoA content and fatty acid oxidation rates in skeletal muscle of Acc2KO mice were unchanged, suggesting metabolic compensation in response to the loss of Acc2. The limited impact of Acc2 deletion on energy balance raises the possibility that selective pharmacological inhibition of Acc2 for the treatment of obesity may be ineffective.
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129
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A different mechanism for the inhibition of the carboxyltransferase domain of acetyl-coenzyme A carboxylase by tepraloxydim. Proc Natl Acad Sci U S A 2009; 106:20723-7. [PMID: 19926852 DOI: 10.1073/pnas.0908431106] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Acetyl-CoA carboxylases (ACCs) are crucial metabolic enzymes and are attractive targets for drug discovery. Haloxyfop and tepraloxydim belong to two distinct classes of commercial herbicides and kill sensitive plants by inhibiting the carboxyltransferase (CT) activity of ACC. Our earlier structural studies showed that haloxyfop is bound near the active site of the CT domain, at the interface of its dimer, and a large conformational change in the dimer interface is required for haloxyfop binding. We report here the crystal structure at 2.3 A resolution of the CT domain of yeast ACC in complex with tepraloxydim. The compound has a different mechanism of inhibiting the CT activity compared to haloxyfop, as well as the mammalian ACC inhibitor CP-640186. Tepraloxydim probes a different region of the dimer interface and requires only small but important conformational changes in the enzyme, in contrast to haloxyfop. The binding mode of tepraloxydim explains the structure-activity relationship of these inhibitors, and provides a molecular basis for their distinct sensitivity to some of the resistance mutations, as compared to haloxyfop. Despite the chemical diversity between haloxyfop and tepraloxydim, the compounds do share two binding interactions to the enzyme, which may be important anchoring points for the development of ACC inhibitors.
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130
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Li DQ, Ohshiro K, Reddy SDN, Pakala SB, Lee MH, Zhang Y, Rayala SK, Kumar R. E3 ubiquitin ligase COP1 regulates the stability and functions of MTA1. Proc Natl Acad Sci U S A 2009; 106:17493-8. [PMID: 19805145 PMCID: PMC2762678 DOI: 10.1073/pnas.0908027106] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2009] [Indexed: 11/18/2022] Open
Abstract
Metastasis-associated protein 1 (MTA1), a component of the nucleosome remodeling and histone deacetylation (NuRD) complex, is widely upregulated in human cancers. However, the mechanism for regulating its protein stability remains unknown. Here we report that MTA1 is an ubiquitinated protein and targeted by the RING-finger E3 ubiquitin-protein ligase constitutive photomorphogenesis protein 1 (COP1) for degradation via the ubiquitin-proteasome pathway. Induced expression of wild-type COP1 but not its RING motif mutants promotes the ubiquitination and degradation of MTA1, indicating that the ligase activity is required for the COP1-mediated proteolysis of MTA1. Conversely, depletion of endogenous COP1 resulted in a marked decrease in MTA1 ubiquitination, accompanied by a pronounced accumulation of MTA1 protein. MTA1, in turn, destabilizes COP1 by promoting its autoubiquitination, thus creating a tight feedback loop that regulates both MTA1 and COP1 protein stability. Accordingly, disruption of the COP1-mediated proteolysis by ionizing radiation leads to MTA1 stabilization, accompanied by an increased coregulatory function of MTA1 on its target. Furthermore, we discovered that MTA1 is required for optimum DNA double-strand break repair after ionizing radiation. These findings provide novel insights into the regulation of MTA1 protein and reveal a novel function of MTA1 in DNA damage response.
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Affiliation(s)
- Da-Qiang Li
- Department of Biochemistry and Molecular Biology and Institute of Coregulator Biology, The George Washington University Medical Center, Washington, DC 20037
| | - Kazufumi Ohshiro
- Department of Biochemistry and Molecular Biology and Institute of Coregulator Biology, The George Washington University Medical Center, Washington, DC 20037
| | - Sirigiri Divijendra Natha Reddy
- Department of Biochemistry and Molecular Biology and Institute of Coregulator Biology, The George Washington University Medical Center, Washington, DC 20037
| | - Suresh B. Pakala
- Department of Biochemistry and Molecular Biology and Institute of Coregulator Biology, The George Washington University Medical Center, Washington, DC 20037
| | - Mong-Hong Lee
- Department of Molecular & Cellular Oncology, The University of Texas M. D. Anderson Cancer Center, Houston, TX 77030; and
| | - Yanping Zhang
- Radiation Oncology and Lineberger Comprehensive Cancer Center, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
| | - Suresh K. Rayala
- Department of Biochemistry and Molecular Biology and Institute of Coregulator Biology, The George Washington University Medical Center, Washington, DC 20037
| | - Rakesh Kumar
- Department of Biochemistry and Molecular Biology and Institute of Coregulator Biology, The George Washington University Medical Center, Washington, DC 20037
- Department of Molecular & Cellular Oncology, The University of Texas M. D. Anderson Cancer Center, Houston, TX 77030; and
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131
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Haque TS, Liang N, Golla R, Seethala R, Ma Z, Ewing WR, Cooper CB, Pelleymounter MA, Poss MA, Cheng D. Potent biphenyl- and 3-phenyl pyridine-based inhibitors of acetyl-CoA carboxylase. Bioorg Med Chem Lett 2009; 19:5872-6. [DOI: 10.1016/j.bmcl.2009.08.077] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2009] [Revised: 08/20/2009] [Accepted: 08/21/2009] [Indexed: 10/20/2022]
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132
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Law IKM, Liu L, Xu A, Lam KSL, Vanhoutte PM, Che CM, Leung PTY, Wang Y. Identification and characterization of proteins interacting with SIRT1 and SIRT3: implications in the anti-aging and metabolic effects of sirtuins. Proteomics 2009; 9:2444-56. [PMID: 19343720 DOI: 10.1002/pmic.200800738] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Sirtuins are a family of NAD(+)-dependent protein deacetylases that regulate cellular functions through deacetylation of a wide range of protein targets. Overexpression of Sir2, the first gene discovered in this family, is able to extend the life span in various organisms. The anti-aging effects of human homologues of sirtuins, SIRT1-7, have also been suggested by animal and human association studies. However, the precise mechanisms whereby sirtuins exert their anti-aging effects remain elusive. In this study, we aim to identify novel interacting partners of SIRT1 and SIRT3, two human sirtuins ubiquitously expressed in many tissue types. Our results demonstrate that SIRT1 and SIRT3 are localized within different intracellular compartments, mainly nuclei and mitochondria, respectively. Using affinity purification and MALDI-TOF/TOF-MS/MS analysis, their potential interacting partners have been identified from the enriched subcellular fractions and specific interactions confirmed by co-immunoprecipitation and Western blotting experiment. Further analyses suggest that overexpression of SIRT1 or SIRT3 in HEK293 cells could induce hypoacetylation and affect the intracellular localizations and protein stabilities of their interacting partners. Taken together, the present study has identified a number of novel SIRT protein interacting partners, which might be critically involved in the anti-aging and metabolic regulatory activities of sirtuins.
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Affiliation(s)
- Ivy K M Law
- Department of Pharmacology and Pharmacy, University of Hong Kong, Hong Kong, China
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133
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Way TD, Lin HY, Kuo DH, Tsai SJ, Shieh JC, Wu JC, Lee MR, Lin JK. Pu-erh tea attenuates hyperlipogenesis and induces hepatoma cells growth arrest through activating AMP-activated protein kinase (AMPK) in human HepG2 cells. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2009; 57:5257-5264. [PMID: 19459711 DOI: 10.1021/jf900730e] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
In the present study, we successively extracted the pu-erh raw tea with methanol (PR-1), chloroform (PR-2), ethyl acetate (PR-3), n-butanol (PR-4), and water (PR-5). Among these extracts, PR-3 extract contained ingredients with the most effective hypolipidemic potential and was further purified by column chromatography. Moreover, chronic administration of PR-3 provoked a significant reduction in levels of serum triglyceride and low-density lipoprotein (LDL) in rats. Our study demonstrated that fraction 5 from the PR-3 extract (PR-3-5s) showed a hypolipidemic effect in human hepatoma HepG2 cells. PR-3-5s decreased the expression of fatty acid synthase (FASN) and inhibited the activity of acetyl-coenzyme A carboxylase (ACC) by stimulating AMP-activated protein kinase (AMPK) through the LKB1 pathway. Moreover, PR-3-5s blocked the progression of the cell cycle at the G1 phase by inducing p53 expression and in turn upregulating p21 expression.
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Affiliation(s)
- Tzong-Der Way
- Department of Biological Science and Technology, College of Life Sciences, China Medical University, Taichung, Taiwan
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134
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Corbett JW. Review of recent acetyl-CoA carboxylase inhibitor patents: mid-2007 – 2008. Expert Opin Ther Pat 2009; 19:943-56. [DOI: 10.1517/13543770902862180] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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135
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Discovery of small molecule isozyme non-specific inhibitors of mammalian acetyl-CoA carboxylase 1 and 2. Bioorg Med Chem Lett 2009; 20:2383-8. [PMID: 20219367 DOI: 10.1016/j.bmcl.2009.04.091] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2009] [Revised: 04/19/2009] [Accepted: 04/21/2009] [Indexed: 11/24/2022]
Abstract
Screening Pfizer's compound library resulted in the identification of weak acetyl-CoA carboxylase inhibitors, from which were obtained rACC1 CT-domain co-crystal structures. Utilizing HTS hits and structure-based drug discovery, a more rigid inhibitor was designed and led to the discovery of sub-micromolar, spirochromanone non-specific ACC inhibitors. Low nanomolar, non-specific ACC-isozyme inhibitors that exhibited good rat pharmacokinetics were obtained from this chemotype.
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136
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Blomme EA, Yang Y, Waring JF. Use of toxicogenomics to understand mechanisms of drug-induced hepatotoxicity during drug discovery and development. Toxicol Lett 2009; 186:22-31. [DOI: 10.1016/j.toxlet.2008.09.017] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2008] [Revised: 09/10/2008] [Accepted: 09/22/2008] [Indexed: 12/26/2022]
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137
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Hallén S, Clapham JC. Cell based in vitro and ex vivo models in metabolic disease drug discovery: nice to have or critical path? Expert Opin Drug Discov 2009; 4:417-28. [PMID: 23485042 DOI: 10.1517/17460440902821640] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
BACKGROUND The use of cellular models as tools in drug discovery is almost universal. However, in disease areas such as metabolic diseases, are they relevant to the process and do they add value? OBJECTIVE In this article, we explore the variety of cellular models now used in drug discovery in metabolic diseases as revealed by publication. We have tried to make some connections between drug phenotypes in these models with clinical parallels. We also ask the question as to whether such models add value in the drug discovery process. This overview is not about recombinant cell systems used in target-based screening; rather, we focus on in vitro, including ex vivo, models as physiological systems in drug discovery in obesity and diabetes. CONCLUSION In terms of building target confidence, in vitro models are often the only mechanistic link to human systems early in a projects life. Many of the current targets in metabolic diseases in the early discovery phase are not yet clinically supported, let alone validated. In this respect, therefore, in vitro models warrant a place in the critical path in early discovery. In terms of any predictive role for decision-making today, this is much more difficult and is more likely pushed to a supporting role as part of a wider package. However, there is a rapid rate of advancement in this field and future developments hold much promise.
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Affiliation(s)
- Stefan Hallén
- Departments of Bioscience, AstraZeneca R&D Mölndal, Sweden +46 31 7064339 ; +46 31 7763700 ;
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138
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Synthesis and characterization of a BODIPY-labeled derivative of Soraphen A that binds to acetyl-CoA carboxylase. Bioorg Med Chem Lett 2009; 19:2804-7. [PMID: 19359168 DOI: 10.1016/j.bmcl.2009.03.107] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2009] [Revised: 03/20/2009] [Accepted: 03/23/2009] [Indexed: 11/22/2022]
Abstract
BODIPY-labeled Soraphen A derivative 4 was synthesized and characterized as an acetyl-CoA carboxylase (ACC) binder. Biophysical measurements indicate that the molecule binds in the biotin carboxylase domain where Soraphen A has been shown to bind. The fluorescent label of the BODIPY can be used to biophysically identify a compound that binds to the Soraphen A site of the biotin carboxylase domain versus the carboxytransferase domain of ACC.
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139
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Chou CY, Yu LPC, Tong L. Crystal structure of biotin carboxylase in complex with substrates and implications for its catalytic mechanism. J Biol Chem 2009; 284:11690-7. [PMID: 19213731 DOI: 10.1074/jbc.m805783200] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Biotin-dependent carboxylases are widely distributed in nature and have important functions in many cellular processes. These enzymes share a conserved biotin carboxylase (BC) component, which catalyzes the ATP-dependent carboxylation of biotin using bicarbonate as the donor. Despite the availability of a large amount of biochemical and structural information on BC, the molecular basis for its catalysis is currently still poorly understood. We report here the crystal structure at 2.0 A resolution of wild-type Escherichia coli BC in complex with its substrates biotin, bicarbonate, and Mg-ADP. The structure suggests that Glu(296) is the general base that extracts the proton from bicarbonate, and Arg(338) is the residue that stabilizes the enolate biotin intermediate in the carboxylation reaction. The B domain of BC is positioned closer to the active site, leading to a 2-A shift in the bound position of the adenine nucleotide and bringing it near the bicarbonate for catalysis. One of the oxygen atoms of bicarbonate is located in the correct position to initiate the nucleophilic attack on ATP to form the carboxyphosphate intermediate. This oxygen is also located close to the N1' atom of biotin, providing strong evidence that the phosphate group, derived from decomposition of carboxyphosphate, is the general base that extracts the proton on this N1' atom. The structural observations are supported by mutagenesis and kinetic studies. Overall, this first structure of BC in complex with substrates offers unprecedented insights into the molecular mechanism for the catalysis by this family of enzymes.
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Affiliation(s)
- Chi-Yuan Chou
- Department of Biological Sciences, Columbia University, New York, New York 10027, USA
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140
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Guillou H, Martin PGP, Pineau T. Transcriptional regulation of hepatic fatty acid metabolism. Subcell Biochem 2008; 49:3-47. [PMID: 18751906 DOI: 10.1007/978-1-4020-8831-5_1] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The liver is a major site of fatty acid synthesis and degradation. Transcriptional regulation is one of several mechanisms controlling hepatic metabolism of fatty acids. Two transcription factors, namely SREBP1-c and PPARalpha, appear to be the main players controlling synthesis and degradation of fatty acids respectively. This chapter briefly presents fatty acid metabolism. The first part focuses on SREBP1-c contribution to the control of gene expression relevant to fatty acid synthesis and the main mechanisms of activation for this transcriptional program. The second part reviews the evidence for the involvement of PPARalpha in the control of fatty acid degradation and the key features of this nuclear receptor. Finally, the third part aims at summarizing recent advances in our current understanding of how these two transcription factors fit in the regulatory networks that sense hormones or nutrients, including cellular fatty acids, and govern the transcription of genes implicated in hepatic fatty acid metabolism.
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Affiliation(s)
- Hervé Guillou
- Laboratoire de Pharmacologie et Toxicologie UR66, INRA, F-3100 Toulouse, France
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141
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Kato S, Ding J, Pisck E, Jhala US, Du K. COP1 functions as a FoxO1 ubiquitin E3 ligase to regulate FoxO1-mediated gene expression. J Biol Chem 2008; 283:35464-73. [PMID: 18815134 PMCID: PMC2602905 DOI: 10.1074/jbc.m801011200] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2008] [Revised: 09/22/2008] [Indexed: 02/06/2023] Open
Abstract
COP1 is a Ring-Finger E3 ubiquitin ligase that is involved in plant development, mammalian cell survival, growth, and metabolism. Here we report that COP1, whose expression is enhanced by insulin, regulates FoxO1 protein stability. We found that in Fao hepatoma cells, ectopic expression of COP1 decreased, whereas knockdown of COP1 expression increased the level of endogenous FoxO1 protein without impacting other factors such as C/EBPalpha and CREB (cAMP-response element-binding protein). We further showed that COP1 binds FoxO1, enhances its ubiquitination, and promotes its degradation via the ubiquitin-proteasome pathway. To determine the biological significance of COP1-mediated FoxO1 protein degradation, we have examined the impact of COP1 on FoxO1-mediated gene expression and found that COP1 suppressed FoxO1 reporter gene as well as FoxO1 target genes such as glucose-6-phosphatase and phosphoenolpyruvate carboxykinase, two key targets for FoxO1 in the regulation of gluconeogenesis, with corresponding changes of hepatic glucose production in Fao cells. We suggest that by functioning as a FoxO1 E3 ligase, COP1 may play a role in the regulation of hepatic glucose metabolism.
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Affiliation(s)
- Satomi Kato
- Molecular Oncology Research Institute, Tufts-New England Medical Center, Boston, Massachusetts 02111, USA
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142
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Abstract
Fatty acids are a major energy source and important constituents of membrane lipids, and they serve as cellular signaling molecules that play an important role in the etiology of the metabolic syndrome. Acetyl-CoA carboxylases 1 and 2 (ACC1 and ACC2) catalyze the synthesis of malonyl-CoA, the substrate for fatty acid synthesis and the regulator of fatty acid oxidation. They are highly regulated and play important roles in the energy metabolism of fatty acids in animals, including humans. They are presently considered as an attractive target to regulate the human diseases of obesity, diabetes, cancer, and cardiovascular complications. In this review we discuss the role of fatty acid metabolism and its key players, ACC1 and ACC2, in animal evolution and physiology, as related to health and disease.
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Affiliation(s)
- Salih J Wakil
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, TX 77030, USA.
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143
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Systems-level metabolic flux profiling identifies fatty acid synthesis as a target for antiviral therapy. Nat Biotechnol 2008; 26:1179-86. [PMID: 18820684 DOI: 10.1038/nbt.1500] [Citation(s) in RCA: 493] [Impact Index Per Article: 30.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2008] [Accepted: 09/08/2008] [Indexed: 12/12/2022]
Abstract
Viruses rely on the metabolic network of their cellular hosts to provide energy and building blocks for viral replication. We developed a flux measurement approach based on liquid chromatography-tandem mass spectrometry to quantify changes in metabolic activity induced by human cytomegalovirus (HCMV). This approach reliably elucidated fluxes in cultured mammalian cells by monitoring metabolome labeling kinetics after feeding cells (13)C-labeled forms of glucose and glutamine. Infection with HCMV markedly upregulated flux through much of the central carbon metabolism, including glycolysis. Particularly notable increases occurred in flux through the tricarboxylic acid cycle and its efflux to the fatty acid biosynthesis pathway. Pharmacological inhibition of fatty acid biosynthesis suppressed the replication of both HCMV and influenza A, another enveloped virus. These results show that fatty acid synthesis is essential for the replication of two divergent enveloped viruses and that systems-level metabolic flux profiling can identify metabolic targets for antiviral therapy.
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144
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Differential activation of recombinant human acetyl-CoA carboxylases 1 and 2 by citrate. Arch Biochem Biophys 2008; 475:72-9. [DOI: 10.1016/j.abb.2008.04.011] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2008] [Revised: 04/11/2008] [Accepted: 04/13/2008] [Indexed: 11/22/2022]
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145
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Mosca R, Schneider TR. RAPIDO: a web server for the alignment of protein structures in the presence of conformational changes. Nucleic Acids Res 2008; 36:W42-6. [PMID: 18460546 PMCID: PMC2447786 DOI: 10.1093/nar/gkn197] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Rapid alignment of proteins in terms of domains (RAPIDO) is a web server for the 3D alignment of crystal structures of different protein molecules in the presence of conformational change. The structural alignment algorithm identifies groups of equivalent atoms whose interatomic distances are constant (within a defined tolerance) in the two structures being compared and considers these groups of atoms as rigid bodies. In addition to the functionalities provided by existing tools, RAPIDO can identify structurally equivalent regions also when these consist of fragments that are distant in terms of sequence and separated by other movable domains. Furthermore, RAPIDO takes the variation in the reliability of atomic coordinates into account in the comparison of distances between equivalent atoms by employing weighting-functions based on the refined B-values. The regions identified as equivalent by RAPIDO furnish reliable sets of residues for the superposition of the two structures for subsequent detailed analysis. The RAPIDO server, with related documentation, is available at http://webapps.embl-hamburg.de/rapido.
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Affiliation(s)
- Roberto Mosca
- IFOM, the FIRC Institute for Molecular Oncology Foundation, Via Adamello 16, 20139, European Institute of Oncology, Via Ripamonti 435, 20141 Milan, Italy
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146
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Ronnebaum SM, Joseph JW, Ilkayeva O, Burgess SC, Lu D, Becker TC, Sherry AD, Newgard CB. Chronic suppression of acetyl-CoA carboxylase 1 in beta-cells impairs insulin secretion via inhibition of glucose rather than lipid metabolism. J Biol Chem 2008; 283:14248-56. [PMID: 18381287 DOI: 10.1074/jbc.m800119200] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Acetyl-CoA carboxylase 1 (ACC1) currently is being investigated as a target for treatment of obesity-associated dyslipidemia and insulin resistance. To investigate the effects of ACC1 inhibition on insulin secretion, three small interfering RNA (siRNA) duplexes targeting ACC1 (siACC1) were transfected into the INS-1-derived cell line, 832/13; the most efficacious duplex was also cloned into an adenovirus and used to transduce isolated rat islets. Delivery of the siACC1 duplexes decreased ACC1 mRNA by 60-80% in 832/13 cells and islets and enzyme activity by 46% compared with cells treated with a non-targeted siRNA. Delivery of siACC1 decreased glucose-stimulated insulin secretion (GSIS) by 70% in 832/13 cells and by 33% in islets. Surprisingly, siACC1 treatment decreased glucose oxidation by 49%, and the ATP:ADP ratio by 52%, accompanied by clear decreases in pyruvate cycling activity and tricarboxylic acid cycle intermediates. Exposure of siACC1-treated cells to the pyruvate cycling substrate dimethylmalate restored GSIS to normal without recovery of the depressed ATP:ADP ratio. In siACC1-treated cells, glucokinase protein levels were decreased by 25%, which correlated with a 36% decrease in glycogen synthesis and a 33% decrease in glycolytic flux. Furthermore, acute addition of the ACC1 inhibitor 5-(tetradecyloxy)-2-furoic acid (TOFA) to beta-cells suppressed [(14)C]glucose incorporation into lipids but had no effect on GSIS, whereas chronic TOFA administration suppressed GSIS and glucose metabolism. In sum, chronic, but not acute, suppression of ACC1 activity impairs GSIS via inhibition of glucose rather than lipid metabolism. These findings raise concerns about the use of ACC inhibitors for diabetes therapy.
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Affiliation(s)
- Sarah M Ronnebaum
- Sarah W Stedman Nutrition and Metabolism Center and Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC 27704, USA
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147
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Bagautdinov B, Matsuura Y, Bagautdinova S, Kunishima N. Protein biotinylation visualized by a complex structure of biotin protein ligase with a substrate. J Biol Chem 2008; 283:14739-50. [PMID: 18372281 DOI: 10.1074/jbc.m709116200] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Biotin protein ligase (BPL) catalyzes the biotinylation of the biotin carboxyl carrier protein (BCCP) only at a special lysine residue. Here we report the first structure of BPL.BCCP complex crystals, which are prepared using two BPL mutants: R48A and R48A/K111A. From a detailed structural characterization, it is likely that the mutants retain functionality as enzymes but have a reduced activity to produce the reaction intermediate biotinyl-5'-AMP. The observed biotin and partly disordered ATP in the mutant structures may act as a non-reactive analog of the substrates or biotinyl-5'-AMP, thereby providing the complex crystals. The four crystallographically independent BPL.BCCP complexes obtained can be classified structurally into three groups: the formation stages 1 and 2 with apo-BCCP and the product stage with biotinylated holo-BCCP. Residues responsible for the complex formation as well as for the biotinylation reaction have been identified. The C-terminal domain of BPL shows especially large conformational changes to accommodate BCCP, suggesting its functional importance. The formation stage 1 complex shows the closest distance between the carboxyl carbon of biotin and the special lysine of BCCP, suggesting its relevance to the unobserved reaction stage. Interestingly, bound ATP and biotin are also seen in the product stage, indicating that the substrates may be recruited into the product stage complex before the release of holo-BCCP, probably for the next reaction cycle. The existence of formation and product stages before and after the reaction stage would be favorable to ensure both the reaction efficiency and the extreme substrate specificity of the biotinylation reaction.
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148
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Keijer J, van Schothorst EM. Adipose tissue failure and mitochondria as a possible target for improvement by bioactive food components. Curr Opin Lipidol 2008; 19:4-10. [PMID: 18196980 DOI: 10.1097/mol.0b013e3282f39f95] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
PURPOSE OF REVIEW Adipose tissue is an essential, highly dynamic and metabolically active tissue that vigorously communicates to support its primary function: the storage of lipids. It performs this function to secure energy supply and prevent lipotoxicity. Adipose tissue is essential for maintaining a healthy glucose and lipid homeostasis and failure results in disease. This review discusses causes of adipose tissue failure and four categories of bioactive food components that may help to prevent this. RECENT FINDINGS Based on recent findings, it is argued that initial adipose failure following long-term excess energy intake may be the result of reduced mitochondrial capacity associated with altered mitochondrial reactive oxygen species signaling and adipose tissue hypoxia. Current data suggest that different classes of bioactive food components, including vitamin B3, retinoids, fatty acids and polyphenols, may have the potential to modulate mitochondrial function and consequently prevent adipose dysfunction in obesity. SUMMARY It seems most attractive to aim nutritional intervention at the prevention of initial adipose dysfunction and hence to target dietary intervention at improvement of mitochondrial function.
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Affiliation(s)
- Jaap Keijer
- RIKILT-Institute of Food Safety, Wageningen, The Netherlands.
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149
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Ma J, Yan R, Zu X, Cheng JM, Rao K, Liao DF, Cao D. Aldo-keto reductase family 1 B10 affects fatty acid synthesis by regulating the stability of acetyl-CoA carboxylase-alpha in breast cancer cells. J Biol Chem 2007; 283:3418-3423. [PMID: 18056116 DOI: 10.1074/jbc.m707650200] [Citation(s) in RCA: 123] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Recent studies have demonstrated that aldo-keto reductase family 1 B10 (AKR1B10), a novel protein overexpressed in human hepatocellular carcinoma and non-small cell lung carcinoma, may facilitate cancer cell growth by detoxifying intracellular reactive carbonyls. This study presents a novel function of AKR1B10 in tumorigenic mammary epithelial cells (RAO-3), regulating fatty acid synthesis. In RAO-3 cells, Sephacryl-S 300 gel filtration and DEAE-Sepharose ion exchange chromatography demonstrated that AKR1B10 exists in two distinct forms, monomers (approximately 40 kDa) bound to DEAE-Sepharose column and protein complexes (approximately 300 kDa) remaining in flow-through. Co-immunoprecipitation with AKR1B10 antibody and protein mass spectrometry analysis identified that AKR1B10 associates with acetyl-CoA carboxylase-alpha (ACCA), a rate-limiting enzyme of de novo fatty acid synthesis. This association between AKR1B10 and ACCA proteins was further confirmed by co-immunoprecipitation with ACCA antibody and pulldown assays with recombinant AKR1B10 protein. Intracellular fluorescent studies showed that AKR1B10 and ACCA proteins co-localize in the cytoplasm of RAO-3 cells. More interestingly, small interfering RNA-mediated AKR1B10 knock down increased ACCA degradation through ubiquitination-proteasome pathway and resulted in >50% decrease of fatty acid synthesis in RAO-3 cells. These data suggest that AKR1B10 is a novel regulator of the biosynthesis of fatty acid, an essential component of the cell membrane, in breast cancer cells.
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Affiliation(s)
- Jun Ma
- Department of Medical Microbiology, Immunology, and Cell Biology, SimmonsCooper Cancer InstituteSouthern Illinois University School of Medicine, Springfield, Illinois 62702
| | - Ruilan Yan
- Department of Medical Microbiology, Immunology, and Cell Biology, SimmonsCooper Cancer InstituteSouthern Illinois University School of Medicine, Springfield, Illinois 62702
| | - Xuyu Zu
- Department of Medical Microbiology, Immunology, and Cell Biology, SimmonsCooper Cancer InstituteSouthern Illinois University School of Medicine, Springfield, Illinois 62702; Division of Pharmacoproteomics, Institute of Pharmacy and Pharmacology, Nanhua University School of Life Science and Technology, 28 Changshengxi Road, Hengyang, Hunan 421001, China
| | - Ji-Ming Cheng
- Division of Hematology/Oncology, Internal Medicine, Southern Illinois University School of Medicine, Springfield, Illinois 62702
| | - Krishna Rao
- Department of Medical Microbiology, Immunology, and Cell Biology, SimmonsCooper Cancer InstituteSouthern Illinois University School of Medicine, Springfield, Illinois 62702; Division of Hematology/Oncology, Internal Medicine, Southern Illinois University School of Medicine, Springfield, Illinois 62702
| | - Duan-Fang Liao
- Division of Pharmacoproteomics, Institute of Pharmacy and Pharmacology, Nanhua University School of Life Science and Technology, 28 Changshengxi Road, Hengyang, Hunan 421001, China
| | - Deliang Cao
- Department of Medical Microbiology, Immunology, and Cell Biology, SimmonsCooper Cancer InstituteSouthern Illinois University School of Medicine, Springfield, Illinois 62702.
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150
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Liu W, Harrison DK, Chalupska D, Gornicki P, O'Donnell CC, Adkins SW, Haselkorn R, Williams RR. Single-site mutations in the carboxyltransferase domain of plastid acetyl-CoA carboxylase confer resistance to grass-specific herbicides. Proc Natl Acad Sci U S A 2007; 104:3627-32. [PMID: 17360693 PMCID: PMC1802000 DOI: 10.1073/pnas.0611572104] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Grass weed populations resistant to aryloxyphenoxypropionate (APP) and cyclohexanedione herbicides that inhibit acetyl-CoA carboxylase (ACCase; EC 6.4.1.2) represent a major problem for sustainable agriculture. We investigated the molecular basis of resistance to ACCase-inhibiting herbicides for nine wild oat (Avena sterilis ssp. ludoviciana Durieu) populations from the northern grain-growing region of Australia. Five amino acid substitutions in plastid ACCase were correlated with herbicide resistance: Ile-1,781-Leu, Trp-1,999-Cys, Trp-2,027-Cys, Ile-2,041-Asn, and Asp-2,078-Gly (numbered according to the Alopecurus myosuroides plastid ACCase). An allele-specific PCR test was designed to determine the prevalence of these five mutations in wild oat populations suspected of harboring ACCase-related resistance with the result that, in most but not all cases, plant resistance was correlated with one (and only one) of the five mutations. We then showed, using a yeast gene-replacement system, that these single-site mutations also confer herbicide resistance to wheat plastid ACCase: Ile-1,781-Leu and Asp-2,078-Gly confer resistance to APPs and cyclohexanediones, Trp-2,027-Cys and Ile-2,041-Asn confer resistance to APPs, and Trp-1,999-Cys confers resistance only to fenoxaprop. These mutations are very likely to confer resistance to any grass weed species under selection imposed by the extensive agricultural use of the herbicides.
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Affiliation(s)
- Wenjie Liu
- *Agricultural Molecular Biotechnology Laboratory, School of Agronomy and Horticulture, University of Queensland, Gatton 4343, Queensland, Australia
| | - Dion K. Harrison
- *Agricultural Molecular Biotechnology Laboratory, School of Agronomy and Horticulture, University of Queensland, Gatton 4343, Queensland, Australia
- To whom correspondence may be addressed. E-mail: or
| | - Dominika Chalupska
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL 60637
| | - Piotr Gornicki
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL 60637
| | - Chris C. O'Donnell
- Tropical and Subtropical Weeds Research Unit, School of Land and Food Sciences, University of Queensland, Brisbane 4072, Queensland, Australia; and
| | - Steve W. Adkins
- Tropical and Subtropical Weeds Research Unit, School of Land and Food Sciences, University of Queensland, Brisbane 4072, Queensland, Australia; and
| | - Robert Haselkorn
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL 60637
- To whom correspondence may be addressed. E-mail: or
| | - Richard R. Williams
- *Agricultural Molecular Biotechnology Laboratory, School of Agronomy and Horticulture, University of Queensland, Gatton 4343, Queensland, Australia
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