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Sekiya M, Kainoh K, Saito K, Yamazaki D, Tsuyuzaki T, Chen W, Kobari Y, Nakata A, Babe H, Shimano H. C-Terminal Binding Protein 2 Emerges as a Critical Player Linking Metabolic Imbalance to the Pathogenesis of Obesity. J Atheroscler Thromb 2024; 31:109-116. [PMID: 37793810 PMCID: PMC10857841 DOI: 10.5551/jat.rv22014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Accepted: 08/21/2023] [Indexed: 10/06/2023] Open
Abstract
Metabolism is one of the vital functions of cells and living organisms, and the systems to sense and respond to the metabolic alterations play pivotal roles in a plethora of biological processes, including cell proliferative activities, immune cell functions, aging processes, and neuronal functions. Recently, we have reported that a transcriptional cofactor, C-terminal binding protein 2 (CtBP2), serves as a critical metabolite sensor in this context. CtBP2 has a structural pocket called Rossmann fold to accommodate metabolites, and it has been reported to be activated upon binding to NADH/NAD+. Owing to its preferential binding affinity for NADH compared with NAD+, increased glycolysis activates CtBP2 by regenerating NADH from NAD+. Furthermore, we recently reported that fatty acyl-CoAs, metabolites accumulated under the condition of lipid overload, as represented by obesity, can inactivate CtBP2. These observations suggest that CtBP2 monitors not only redox state but also energy substrate preference in the maintenance of metabolic homeostasis. In line with these metabolite-sensing capabilities, CtBP2 is activated in healthy subjects to protect against metabolic disturbances, whereas inactivation of CtBP2 in obesity contributes to the pathogeneses of obesity.This metabolic system orchestrated by CtBP2 can provide a novel framework for understanding how cells maintain their homeostasis through coordination of metabolism, and CtBP2 incapacitation can be a critical point of the obesogenic cascade.
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Affiliation(s)
- Motohiro Sekiya
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, Ibaraki, Japan
| | - Kenta Kainoh
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, Ibaraki, Japan
| | - Kenji Saito
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, Ibaraki, Japan
| | - Daichi Yamazaki
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, Ibaraki, Japan
| | - Tomomi Tsuyuzaki
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, Ibaraki, Japan
| | - Wanpei Chen
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, Ibaraki, Japan
| | - Yuto Kobari
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, Ibaraki, Japan
| | - Ayumi Nakata
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, Ibaraki, Japan
| | - Haruka Babe
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, Ibaraki, Japan
| | - Hitoshi Shimano
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, Ibaraki, Japan
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Sekiya M, Ma Y, Kainoh K, Saito K, Yamazaki D, Tsuyuzaki T, Chen W, Adi Putri PIP, Ohno H, Miyamoto T, Takeuchi Y, Murayama Y, Sugano Y, Osaki Y, Iwasaki H, Yahagi N, Suzuki H, Motomura K, Matsuzaka T, Murata K, Mizuno S, Takahashi S, Shimano H. Loss of CtBP2 may be a mechanistic link between metabolic derangements and progressive impairment of pancreatic β cell function. Cell Rep 2023; 42:112914. [PMID: 37557182 DOI: 10.1016/j.celrep.2023.112914] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 06/19/2023] [Accepted: 07/16/2023] [Indexed: 08/11/2023] Open
Abstract
The adaptive increase in insulin secretion in early stages of obesity serves as a safeguard mechanism to maintain glucose homeostasis that cannot be sustained, and the eventual decompensation of β cells is a key event in the pathogenesis of diabetes. Here we describe a crucial system orchestrated by a transcriptional cofactor CtBP2. In cultured β cells, insulin gene expression is coactivated by CtBP2. Global genomic mapping of CtBP2 binding sites identifies a key interaction between CtBP2 and NEUROD1 through which CtBP2 decompacts chromatin in the insulin gene promoter. CtBP2 expression is diminished in pancreatic islets in multiple mouse models of obesity, as well as human obesity. Pancreatic β cell-specific CtBP2-deficient mice manifest glucose intolerance with impaired insulin secretion. Our transcriptome analysis highlights an essential role of CtBP2 in the maintenance of β cell integrity. This system provides clues to the molecular basis in obesity and may be targetable to develop therapeutic approaches.
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Affiliation(s)
- Motohiro Sekiya
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8575, Ibaraki, Japan.
| | - Yang Ma
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8575, Ibaraki, Japan
| | - Kenta Kainoh
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8575, Ibaraki, Japan
| | - Kenji Saito
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8575, Ibaraki, Japan
| | - Daichi Yamazaki
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8575, Ibaraki, Japan
| | - Tomomi Tsuyuzaki
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8575, Ibaraki, Japan
| | - Wanpei Chen
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8575, Ibaraki, Japan
| | - Putu Indah Paramita Adi Putri
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8575, Ibaraki, Japan
| | - Hiroshi Ohno
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8575, Ibaraki, Japan
| | - Takafumi Miyamoto
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8575, Ibaraki, Japan
| | - Yoshinori Takeuchi
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8575, Ibaraki, Japan
| | - Yuki Murayama
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8575, Ibaraki, Japan
| | - Yoko Sugano
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8575, Ibaraki, Japan
| | - Yoshinori Osaki
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8575, Ibaraki, Japan
| | - Hitoshi Iwasaki
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8575, Ibaraki, Japan
| | - Naoya Yahagi
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8575, Ibaraki, Japan
| | - Hiroaki Suzuki
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8575, Ibaraki, Japan
| | - Kaori Motomura
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8575, Ibaraki, Japan
| | - Takashi Matsuzaka
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8575, Ibaraki, Japan; Transborder Medical Research Center, University of Tsukuba, Tsukuba 305-8575, Ibaraki, Japan
| | - Kazuya Murata
- Laboratory Animal Resource Center in Transborder Medical Research Center, University of Tsukuba, Tsukuba 305-8575, Ibaraki, Japan
| | - Seiya Mizuno
- Laboratory Animal Resource Center in Transborder Medical Research Center, University of Tsukuba, Tsukuba 305-8575, Ibaraki, Japan
| | - Satoru Takahashi
- Laboratory Animal Resource Center in Transborder Medical Research Center, University of Tsukuba, Tsukuba 305-8575, Ibaraki, Japan
| | - Hitoshi Shimano
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8575, Ibaraki, Japan
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Saito K, Sekiya M, Kainoh K, Yoshino R, Hayashi A, Han SI, Araki M, Ohno H, Takeuchi Y, Tsuyuzaki T, Yamazaki D, Wanpei C, Hada L, Watanabe S, Paramita Adi Putri PI, Murayama Y, Sugano Y, Osaki Y, Iwasaki H, Yahagi N, Suzuki H, Miyamoto T, Matsuzaka T, Shimano H. Obesity-induced metabolic imbalance allosterically modulates CtBP2 to inhibit PPAR-alpha transcriptional activity. J Biol Chem 2023:104890. [PMID: 37286039 PMCID: PMC10339064 DOI: 10.1016/j.jbc.2023.104890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2022] [Revised: 05/24/2023] [Accepted: 05/25/2023] [Indexed: 06/09/2023] Open
Abstract
Maintenance of metabolic homeostasis is secured by metabolite-sensing systems, which can be overwhelmed by constant macronutrient surplus in obesity. Not only the uptake processes but also the consumption of energy substrates determine the cellular metabolic burden. We herein describe a novel transcriptional system in this context comprised of peroxisome proliferator-activated receptor alpha (PPARα), a master regulator for fatty acid oxidation, and C-terminal binding protein 2 (CtBP2), a metabolite-sensing transcriptional co-repressor. CtBP2 interacts with PPARα to repress its activity, and the interaction is enhanced upon binding to malonyl-CoA, a metabolic intermediate increased in tissues in obesity and reported to suppress fatty acid oxidation through inhibition of carnitine palmitoyltransferase 1 (CPT1). In line with our preceding observations that CtBP2 adopts a monomeric configuration upon binding to acyl-CoAs, we determined that mutations in CtBP2 that shift the conformational equilibrium toward monomers increase the interaction between CtBP2 and PPARα. In contrast, metabolic manipulations that reduce malonyl-CoA decreased the formation of the CtBP2/PPARα complex. Consistent with these in vitro findings, we found that the CtBP2/PPARα interaction is accelerated in obese livers while genetic deletion of CtBP2 in the liver causes derepression of PPARα target genes. These findings support our model where CtBP2 exists primarily as a monomer in the metabolic milieu of obesity to repress PPARα, representing a liability in metabolic diseases that can be exploited to develop therapeutic approaches.
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Affiliation(s)
- Kenji Saito
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan, 305-8575
| | - Motohiro Sekiya
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan, 305-8575.
| | - Kenta Kainoh
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan, 305-8575
| | - Ryunosuke Yoshino
- Transborder Medical Research Center, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan, 305-8575
| | - Akio Hayashi
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan, 305-8575
| | - Song-Iee Han
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan, 305-8575
| | - Masaya Araki
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan, 305-8575
| | - Hiroshi Ohno
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan, 305-8575
| | - Yoshinori Takeuchi
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan, 305-8575
| | - Tomomi Tsuyuzaki
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan, 305-8575
| | - Daichi Yamazaki
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan, 305-8575
| | - Chen Wanpei
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan, 305-8575
| | - Lisa Hada
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan, 305-8575
| | - Sho Watanabe
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan, 305-8575
| | - Putu Indah Paramita Adi Putri
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan, 305-8575
| | - Yuki Murayama
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan, 305-8575
| | - Yoko Sugano
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan, 305-8575
| | - Yoshinori Osaki
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan, 305-8575
| | - Hitoshi Iwasaki
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan, 305-8575
| | - Naoya Yahagi
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan, 305-8575
| | - Hiroaki Suzuki
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan, 305-8575
| | - Takafumi Miyamoto
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan, 305-8575
| | - Takashi Matsuzaka
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan, 305-8575; Transborder Medical Research Center, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan, 305-8575
| | - Hitoshi Shimano
- Department of Endocrinology and Metabolism, Institute of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan, 305-8575
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Yamazaki D, Osaki Y, Suzuki H, Shimano H. Takotsubo cardiomyopathy with left ventricle thrombus caused by subacute thyroiditis. BMJ Case Rep 2023; 16:16/3/e250540. [PMID: 36918211 PMCID: PMC10016297 DOI: 10.1136/bcr-2022-250540] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023] Open
Abstract
We report a rare case of takotsubo cardiomyopathy caused by subacute thyroiditis in a man in his 50s. He went to the doctor with complaints of loss of appetite, diarrhoea, chills and general malaise. He had consciousness disturbance, thyrotoxicosis and thyroid-stimulating hormone (TSH) suppression. Thyroglobulin and C reactive protein levels in the blood were elevated, but TSH receptor antibody, thyroid-stimulating antibody, antithyroglobulin antibody and antithyroid peroxidase antibody were not. We began treatment with prednisolone and propranolol after he was diagnosed with thyroid storm caused by subacute thyroiditis. The ECG revealed inverted T waves on the fifth day after admission. He was newly diagnosed with takotsubo cardiomyopathy on the day. A large thrombus was detected in the left ventricle, requiring anticoagulation therapy. Thus, even if there are no findings of takotsubo cardiomyopathy or thrombus at the onset of thyroid storm, appropriate monitoring is required because they can develop during the treatment course.
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Affiliation(s)
- Daichi Yamazaki
- Internal Medicine (Endocrinology and Metabolism), University of Tsukuba, Tsukuba, Japan
| | - Yoshinori Osaki
- Internal Medicine (Endocrinology and Metabolism), University of Tsukuba, Tsukuba, Japan
| | - Hiroaki Suzuki
- Internal Medicine (Endocrinology and Metabolism), University of Tsukuba, Tsukuba, Japan
| | - Hitoshi Shimano
- Internal Medicine (Endocrinology and Metabolism), University of Tsukuba, Tsukuba, Japan
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Nakajima R, Sekiya M, Furuta Y, Miyamoto T, Sato M, Fukuda K, Hattori K, Suehara Y, Sakata-Yanagimoto M, Chiba S, Okajima Y, Matsuzaka T, Takase S, Takanashi M, Okazaki H, Takashima Y, Yuhara M, Mitani Y, Matsumoto N, Murayama Y, Ohyama Osawa M, Ohuchi N, Yamazaki D, Mori S, Sugano Y, Osaki Y, Iwasaki H, Suzuki H, Shimano H. A case of NASH with genetic predisposition successfully treated with an SGLT2 inhibitor: a possible involvement of mitochondrial dysfunction. Endocrinol Diabetes Metab Case Rep 2022; 2022:22-0368. [PMID: 36571472 PMCID: PMC9874953 DOI: 10.1530/edm-22-0368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Accepted: 12/06/2022] [Indexed: 12/27/2022] Open
Abstract
Summary In this study, we herein describe a 47-year-old Japanese woman who manifested inheritable non-alcoholic steatohepatitis (NASH) and severe dyslipidemia. Interestingly, her NASH progression was ameliorated by treatment with a sodium-glucose co-transporter 2 (SGLT2) inhibitor. This inheritability prompted us to comprehensively decode her genomic information using whole-exome sequencing. We found the well-established I148M mutation in PNPLA3 as well as mutations in LGALS3 and PEMT for her NASH. Mutations in GCKR may contribute to both NASH and dyslipidemia. We further mined gene mutations potentially responsible for her manifestations that led to the identification of a novel M188fs mutation in MUL1 that may be causally associated with her mitochondrial dysfunction. Our case may provide some clues to better understand this spectrum of disease as well as the rationale for selecting medications. Learning points While the PNPLA3 I148M mutation is well-established, accumulation of other mutations may accelerate susceptibility to non-alcoholic steatohepatitis (NASH). NASH and dyslipidemia may be intertwined biochemically and genetically through several key genes. SGLT2 inhibitors emerge as promising treatment for NASH albeit with interindividual variation in efficacy. Genetic background may explain the mechanisms behind the variation. A novel dysfunctional mutation in MUL1 may lead to metabolic inflexibilities through impaired mitochondrial dynamics and function.
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Affiliation(s)
- Rikako Nakajima
- Department of Endocrinology and Metabolism, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan
| | - Motohiro Sekiya
- Department of Endocrinology and Metabolism, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan
| | - Yasuhisa Furuta
- Department of Endocrinology and Metabolism, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan
| | - Takafumi Miyamoto
- Department of Endocrinology and Metabolism, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan
| | - Masashi Sato
- Department of Gastroenterology, Faculty of Medicine, University of Tsukuba
| | - Kuniaki Fukuda
- Department of Gastroenterology, Faculty of Medicine, University of Tsukuba
- Department of Gastroenterology, Kasumigaura Medical Center, 2-7-14 Shimotakatsu, Tsuchiura, Ibaraki, Japan
| | - Keiichiro Hattori
- Department of Hematology, Faculty of Medicine, University of Tsukuba
| | - Yasuhito Suehara
- Department of Hematology, Faculty of Medicine, University of Tsukuba
| | | | - Shigeru Chiba
- Department of Hematology, Faculty of Medicine, University of Tsukuba
| | - Yuka Okajima
- Department of Endocrinology and Metabolism, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan
| | - Takashi Matsuzaka
- Department of Endocrinology and Metabolism, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan
- Transborder Medical Research Center, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan
| | - Satoru Takase
- Department of Diabetes and Metabolic Diseases, Graduate School of Medicine, the University of Tokyo, Bunkyo, Tokyo, Japan
| | - Mikio Takanashi
- Department of Diabetes and Metabolic Diseases, Graduate School of Medicine, the University of Tokyo, Bunkyo, Tokyo, Japan
| | - Hiroaki Okazaki
- Department of Diabetes and Metabolic Diseases, Graduate School of Medicine, the University of Tokyo, Bunkyo, Tokyo, Japan
| | - Yusuke Takashima
- Department of Endocrinology and Metabolism, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan
| | - Mikiko Yuhara
- Department of Endocrinology and Metabolism, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan
| | - Yuta Mitani
- Department of Endocrinology and Metabolism, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan
| | - Nako Matsumoto
- Department of Endocrinology and Metabolism, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan
| | - Yuki Murayama
- Department of Endocrinology and Metabolism, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan
| | - Mariko Ohyama Osawa
- Department of Endocrinology and Metabolism, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan
| | - Nami Ohuchi
- Department of Endocrinology and Metabolism, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan
| | - Daichi Yamazaki
- Department of Endocrinology and Metabolism, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan
| | - Sayuri Mori
- Department of Endocrinology and Metabolism, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan
| | - Yoko Sugano
- Department of Endocrinology and Metabolism, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan
| | - Yoshinori Osaki
- Department of Endocrinology and Metabolism, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan
| | - Hitoshi Iwasaki
- Department of Endocrinology and Metabolism, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan
| | - Hiroaki Suzuki
- Department of Endocrinology and Metabolism, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan
| | - Hitoshi Shimano
- Department of Endocrinology and Metabolism, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan
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Sekiya M, Yuhara M, Murayama Y, Ohyama Osawa M, Nakajima R, Ohuchi N, Matsumoto N, Yamazaki D, Mori S, Matsuda T, Sugano Y, Osaki Y, Iwasaki H, Suzuki H, Shimano H. A case of early-onset diabetes with impaired insulin secretion carrying a PAX6 gene Gln135* mutation. Endocrinol Diabetes Metab Case Rep 2022; 2022:22-0271. [PMID: 35979842 PMCID: PMC9422263 DOI: 10.1530/edm-22-0271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Accepted: 07/07/2022] [Indexed: 11/08/2022] Open
Abstract
Summary A paired homeodomain transcription factor, PAX6 (paired-box 6), is essential for the development and differentiation of pancreatic endocrine cells as well as ocular cells. Despite the impairment of insulin secretion observed in PAX6-deficient mice, evidence implicating causal association between PAX6 gene mutations and monogenic forms of human diabetes is limited. We herein describe a 33-year-old Japanese woman with congenital aniridia who was referred to our hospital because of her uncontrolled diabetes with elevated hemoglobin A1c (13.1%) and blood glucose (32.5 mmol/L) levels. Our biochemical analysis revealed that her insulin secretory capacity was modestly impaired as represented by decreased 24-h urinary C-peptide levels (38.0 μg/day), primarily explaining her diabetes. Intriguingly, there was a trend toward a reduction in her serum glucagon levels as well. Based on the well-recognized association of PAX6 gene mutations with congenital aniridia, we screened the whole PAX6 coding sequence, leading to an identification of a heterozygous Gln135* mutation. We tested our idea that this mutation may at least in part explain the impaired insulin secretion observed in this patient. In cultured pancreatic β-cells, exogenous expression of the PAX6 Gln135* mutant produced a truncated protein that lacked the transcriptional activity to induce insulin gene expression. Our observation together with preceding reports support the recent attempt to include PAX6 in the growing list of genes causally responsible for monogenic diabetes. In addition, since most cases of congenital aniridia carry PAX6 mutations, we may need to pay more attention to blood glucose levels in these patients. Learning points PAX6 Gln135* mutation may be causally associated not only with congenital aniridia but also with diabetes. Blood glucose levels may deserve more attention in cases of congenital aniridia with PAX6 mutations. Our case supports the recent attempt to include PAX6 in the list of MODY genes, and Gln135* may be pathogenic.
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Affiliation(s)
- Motohiro Sekiya
- 1Department of Endocrinology and Metabolism, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Mikiko Yuhara
- 1Department of Endocrinology and Metabolism, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Yuki Murayama
- 1Department of Endocrinology and Metabolism, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Mariko Ohyama Osawa
- 1Department of Endocrinology and Metabolism, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Rikako Nakajima
- 1Department of Endocrinology and Metabolism, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Nami Ohuchi
- 1Department of Endocrinology and Metabolism, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Nako Matsumoto
- 1Department of Endocrinology and Metabolism, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Daichi Yamazaki
- 1Department of Endocrinology and Metabolism, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Sayuri Mori
- 1Department of Endocrinology and Metabolism, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Takaaki Matsuda
- 1Department of Endocrinology and Metabolism, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Yoko Sugano
- 1Department of Endocrinology and Metabolism, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Yoshinori Osaki
- 1Department of Endocrinology and Metabolism, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Hitoshi Iwasaki
- 1Department of Endocrinology and Metabolism, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Hiroaki Suzuki
- 1Department of Endocrinology and Metabolism, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Hitoshi Shimano
- 1Department of Endocrinology and Metabolism, Faculty of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan
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7
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Smith MW, Willis T, Alfieri L, James WHM, Trigg MA, Yamazaki D, Hardy AJ, Bisselink B, De Roo A, Macklin MG, Thomas CJ. Incorporating hydrology into climate suitability models changes projections of malaria transmission in Africa. Nat Commun 2020; 11:4353. [PMID: 32859908 PMCID: PMC7455692 DOI: 10.1038/s41467-020-18239-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Accepted: 08/11/2020] [Indexed: 11/21/2022] Open
Abstract
Continental-scale models of malaria climate suitability typically couple well-established temperature-response models with basic estimates of vector habitat availability using rainfall as a proxy. Here we show that across continental Africa, the estimated geographic range of climatic suitability for malaria transmission is more sensitive to the precipitation threshold than the thermal response curve applied. To address this problem we use downscaled daily climate predictions from seven GCMs to run a continental-scale hydrological model for a process-based representation of mosquito breeding habitat availability. A more complex pattern of malaria suitability emerges as water is routed through drainage networks and river corridors serve as year-round transmission foci. The estimated hydro-climatically suitable area for stable malaria transmission is smaller than previous models suggest and shows only a very small increase in state-of-the-art future climate scenarios. However, bigger geographical shifts are observed than with most rainfall threshold models and the pattern of that shift is very different when using a hydrological model to estimate surface water availability for vector breeding. Prior studies mapping climatologically suitable areas for malaria transmission have used relatively simple thresholds for precipitation. Here the authors show that when models incorporate hydrological processes a more complex pattern of malaria suitability emerges in Africa and future shifts in suitability are more pronounced.
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Affiliation(s)
- M W Smith
- School of Geography and Water@Leeds, University of Leeds, Leeds, UK.
| | - T Willis
- School of Geography and Water@Leeds, University of Leeds, Leeds, UK
| | - L Alfieri
- European Commission, Joint Research Centre, Ispra, Italy
| | - W H M James
- School of Geography and Water@Leeds, University of Leeds, Leeds, UK
| | - M A Trigg
- School of Civil Engineering and Water@Leeds, University of Leeds, Leeds, UK
| | - D Yamazaki
- Institute of Industrial Science, The University of Tokyo, Tokyo, Japan
| | - A J Hardy
- Department of Geography and Earth Sciences, Aberystwyth University, Aberystwyth, UK
| | - B Bisselink
- European Commission, Joint Research Centre, Ispra, Italy
| | - A De Roo
- European Commission, Joint Research Centre, Ispra, Italy
| | - M G Macklin
- School of Geography and Lincoln Centre for Water and Planetary Health, University of Lincoln, Lincoln, UK
| | - C J Thomas
- School of Geography and Lincoln Centre for Water and Planetary Health, University of Lincoln, Lincoln, UK
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8
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Tsuji H, Ouchi S, Okune S, Yamazaki D, Hayakawa M, Sato M, Masuda Y, Hosaka A, Tamaoka A. Superficial siderosis of the central nervous system despite successful treatment of cerebral arteriovenous malformation: A case report. Interdisciplinary Neurosurgery 2020. [DOI: 10.1016/j.inat.2020.100671] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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9
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Sougawa M, Sumiya T, Takarabe K, Mori Y, Okada T, Gotou H, Yagi T, Yamazaki D, Tomioka N, Katsura T, Kariyazaki H, Sueoka K, Kunitsugu S. Bond strengths of New Carbon-nitride-Related material C2N2(CH2). ACTA ACUST UNITED AC 2012. [DOI: 10.1088/1742-6596/377/1/012028] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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10
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Ohhara T, Oikawa K, Tamura I, Kaneko K, Kiyanagi R, Kawasaki T, Nakao A, Hanashima T, Munakata K, Nakatani T, Inamura Y, Ito T, Takeda M, Yamazaki D, Hayashida H. Development of software for a new time-of-flight single crystal diffractometer SENJU at J-PARC. Acta Crystallogr A 2011. [DOI: 10.1107/s0108767311083498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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11
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Nagano M, Takai H, Yamazaki D, Maruyama R, Soyama K, Yamamura K. Fabrication of plano-elliptical neutron focusing supermirror by numerically controlled local wet etching with ion beam sputter deposition. ACTA ACUST UNITED AC 2010. [DOI: 10.1088/1742-6596/251/1/012077] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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12
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Judo C, Matsumoto M, Yamazaki D, Hiraide S, Yanagawa Y, Kimura S, Shimamura K, Togashi H. Early stress exposure impairs synaptic potentiation in the rat medial prefrontal cortex underlying contextual fear extinction. Neuroscience 2010; 169:1705-14. [PMID: 20600655 DOI: 10.1016/j.neuroscience.2010.06.035] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2010] [Revised: 06/14/2010] [Accepted: 06/16/2010] [Indexed: 11/15/2022]
Abstract
Traumatic events during early life may affect the neural systems associated with memory function, including extinction, and lead to altered sensitivity to stress later in life. We recently reported that changes in prefrontal synaptic efficacy in response to extinction trials did not occur in adult rats exposed to early postnatal stress (i.e. footshock [FS] stress during postnatal day 21-25 [3W-FS group]). However, identifying neurocircuitry and neural mechanisms responsible for extinction retrieval after extinction training have not been precisely determined. The present study explored whether synaptic transmission in the hippocampal-medial prefrontal cortex (mPFC) neural pathway is altered by extinction retrieval on the day after extinction trials using electrophysiological approaches combined with behavioral analysis. We also elucidated the effects of early postnatal stress on the synaptic response in this neural circuit underlying extinction retrieval. Evoked potential in the mPFC was enhanced following extinction retrieval, accompanied by reduced freezing behavior. This synaptic facilitation (i.e. a long-term potentiation [LTP]-like response) did not occur; rather synaptic inhibition was observed in the 3W-FS group, accompanied by sustained freezing. The behavioral deficit and synaptic inhibition observed in the 3W-FS group were time-dependently ameliorated by the partial N-methyl-D-aspartate (NMDA) receptor agonist D-cycloserine (15 mg/kg, i.p.). These findings suggest that the LTP-like response in the hippocampal-mPFC pathway is associated with extinction retrieval of context-dependent fear memory. Early postnatal stress appears to induce neurodevelopmental dysfunction of this neural circuit and lead to impaired fear extinction later in life. The present data indicate that psychotherapy accompanied by pharmacological interventions that accelerate and strengthen extinction, such as d-cycloserine treatment, may have therapeutic potential for the treatment of anxiety disorders, including posttraumatic stress disorder.
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Affiliation(s)
- C Judo
- Department of Pharmacology, Faculty of Pharmaceutical Sciences, Health Science University of Hokkaido, Ishikari-Tobetsu, 061-0293, Japan
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13
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Ito E, Yoshino T, Yamazaki D, Shatskiy AS, Shan S, Guo X, Katsura T, Higo Y, Funakoshi K. High pressure generation and investigation of the spin transition of ferropericlase (Mg0.83Fe0.17)O. ACTA ACUST UNITED AC 2010. [DOI: 10.1088/1742-6596/215/1/012099] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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14
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Ito H, Okada M, Yamazaki D, Kasai T. Steric Effects in the Scattering of Oriented CH3Cl Molecular Beam from a Si(111) Surface. J Phys Chem A 2009; 114:3080-6. [DOI: 10.1021/jp907225b] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Hironori Ito
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan, Renovation Center of Instruments for Science Education and Technology, Osaka University, 1-2 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan, and PRESTO, Japan Science and Technology Agency, 4-1-18 Honcho, Kawaguchi, Saitama 332-0012, Japan
| | - Michio Okada
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan, Renovation Center of Instruments for Science Education and Technology, Osaka University, 1-2 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan, and PRESTO, Japan Science and Technology Agency, 4-1-18 Honcho, Kawaguchi, Saitama 332-0012, Japan
| | - Daichi Yamazaki
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan, Renovation Center of Instruments for Science Education and Technology, Osaka University, 1-2 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan, and PRESTO, Japan Science and Technology Agency, 4-1-18 Honcho, Kawaguchi, Saitama 332-0012, Japan
| | - Toshio Kasai
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan, Renovation Center of Instruments for Science Education and Technology, Osaka University, 1-2 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan, and PRESTO, Japan Science and Technology Agency, 4-1-18 Honcho, Kawaguchi, Saitama 332-0012, Japan
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Ebisawa T, Soyama K, Yamazaki D, Tasaki S, Sakai K, Oku T, Maruyama R, Hino M. High Intensity Neutron Spin Flip Chopper. Journal of Neutron Research 2005. [DOI: 10.1080/02781070412331298822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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16
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Yamazaki D, Soyama K, Ebisawa T, Tasaki S. Drabkin Energy Filter for Pulse Shaping and Energy Analysis. Journal of Neutron Research 2005. [DOI: 10.1080/10238160412331299979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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17
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Matsubara T, Yamazaki D, Kato M, Hara T, Fujita H, Iwase T, Endo T. An automated classification scheme for mammograms based on amount and distribution of fibroglandular breast tissue density. ACTA ACUST UNITED AC 2001. [DOI: 10.1016/s0531-5131(01)00085-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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18
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Affiliation(s)
- H Itabashi
- Department of Applied Chemistry, Faculty of Engineering, Gunma University, Kiryu, Gunma 376-8515, Japan
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Takaya N, Yamazaki D, Horiuchi H, Ohta A, Takagi M. Cloning and characterization of a chitinase-encoding gene (chiA) from Aspergillus nidulans, disruption of which decreases germination frequency and hyphal growth. Biosci Biotechnol Biochem 1998; 62:60-5. [PMID: 9501518 DOI: 10.1271/bbb.62.60] [Citation(s) in RCA: 95] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
We cloned a chitinase-encoding gene from Aspergillus nidulans by polymerase chain reaction using degenerated oligonucleotide primers designed from the conserved amino acid sequences among chitinases from yeasts and Rhizopus spp. The cloned gene, named chiA, encoded a polypeptide consisting of 660 amino acids. Disruption of chiA had no effect on hyphal or conidiophore morphology, but germination frequency and hyphal growth rate decreased substantially. Expression of chiA was investigated using Escherichia coli beta-galactosidase as a reporter enzyme. The beta-galactosidase activity was present during hyphal growth and increased twice as the conidiophores developed. In situ staining of beta-galactosidase activity found high expression in metulae, phialides, and conidia during conidiophore development, indicating that the expression of chiA is developmentally regulated. This is the first report to isolate a chitinase gene from A. nidulans and investigate its functions using the gene disruption technique and gene fusion methods in filamentous fungi.
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Affiliation(s)
- N Takaya
- Department of Biotechnology, University of Tokyo, Japan
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20
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Abstract
The grain growth rates of MgSiO3 perovskite and periclase in aggregates have been determined at 25 gigapascals and 1573 to 2173 kelvin. The average grain size (G) was fitted to the rate equation, and the grain growth rates of perovskite and periclase were G10.6 = 1 x 10(-57.4) t exp(-320.8/RT) and G10.8 = 1 x 10(-62.3) t exp(-247.0/RT), respectively, where t is the time, R is the gas constant, and T is the absolute temperature. These growth rates provide insight into the mechanism for grain growth in minerals relevant to the Earth's lower mantle that will ultimately help define the rheology of the lower mantle.
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Affiliation(s)
- D Yamazaki
- D. Yamazaki and M. Toriumi, Geological Institute, Faculty of Science, University of Tokyo, Bunkyo, Tokyo 113, Japan. T. Kato, Institute of Geoscience, University of Tsukuba, Tsukuba, Ibaragi 305, Japan. E. Ohtani, Institute of Mineralogy, Petrology and Economic Geology, Tohoku University, Sendai 980-77, Japan
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21
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Ohsawa H, Hagiwara Y, Honda Y, Hanamura S, Nebashi N, Yamazaki D, Kameda T, Igarashi T. [A study of dental soldering. (10) The temperature distribution of infra-red soldering machine]. Nihon Hotetsu Shika Gakkai Zasshi 1990; 34:599-608. [PMID: 1983737 DOI: 10.2186/jjps.34.599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The purpose of this study is to measure the temperature distribution of focused energy by infra-red soldering machine. The result indicate following. 1. The three dimensional heating area is an ellipse shape, and soldering area is about 10 mm in diameter centering around the focus. 2. Temperature adjustment of INFRARED (NEY Co.) is to use Powerlevel, and of BEAMWERDER (YOSHIDA Co.) is adjusting the height of the turn table. 3. When soldering with focused energy with infra-red machine, it is adequate to solder at the focused level or the upper level, after pre-heating of the soldering objects at the lower level.
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Affiliation(s)
- H Ohsawa
- Nihon University Graduate School of Dentistry
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