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Zhang J, Xu Y, Wang C, Tuo X, Zhao X, Qiao W, Tan J. PREB inhibits the replication of prototype foamy virus by affecting its transcription. Virol J 2023; 20:244. [PMID: 37885034 PMCID: PMC10604407 DOI: 10.1186/s12985-023-02211-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2023] [Accepted: 10/13/2023] [Indexed: 10/28/2023] Open
Abstract
BACKGROUND Foamy viruses (FVs) are unique nonpathogenic retroviruses, which remain latent in the host for a long time. Therefore, they may be safe, effective gene transfer vectors. In this study, were assessed FV-host cell interactions and the molecular mechanisms underlying FV latent infection. METHODS We used the prototype FV (PFV) to infect HT1080 cells and a PFV indicator cell line (PFVL) to measure virus titers. After 48 h of infection, the culture supernatant (i.e., cell-free PFV particles) and transfected cells (i.e., cell-associated PFV particles) were harvested and incubated with PFVL. After another 48 h, the luciferase activity was used to measure virus titers. RESULTS Through transcriptomics sequencing, we found that PREB mRNA expression was significantly upregulated. Moreover, PREB overexpression reduced PFV replication, whereas endogenous PREB knockdown increased PFV replication. PREB interacted with the Tas DNA-binding and transcriptional activation domains and interfered with its binding to the PFV long terminal repeat and internal promoter, preventing the recruitment of transcription factors and thereby inhibiting the transactivation function of Tas. PREB C-terminal 329-418 aa played a major role in inhibiting PFV replication; PREB also inhibited bovine FV replication. Therefore, PREB has a broad-spectrum inhibitory effect on FV replication. CONCLUSIONS Our results demonstrated that PREB inhibits PFV replication by impeding its transcription.
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Affiliation(s)
- Junshi Zhang
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, College of Life Sciences, Nankai University, Tianjin, 300071, China
- Department of Hematology, Oncology Centrer, Tianjin Union Medical Center, No.190 Jieyuan Road, Hongqiao District, Tianjin, 300121, P. R. China
| | - Yali Xu
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, College of Life Sciences, Nankai University, Tianjin, 300071, China
| | - Chenchen Wang
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, College of Life Sciences, Nankai University, Tianjin, 300071, China
| | - Xiaopeng Tuo
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, College of Life Sciences, Nankai University, Tianjin, 300071, China
| | - Xingli Zhao
- Department of Hematology, Oncology Centrer, Tianjin Union Medical Center, No.190 Jieyuan Road, Hongqiao District, Tianjin, 300121, P. R. China
| | - Wentao Qiao
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, College of Life Sciences, Nankai University, Tianjin, 300071, China
| | - Juan Tan
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, College of Life Sciences, Nankai University, Tianjin, 300071, China.
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Lyu J, Imachi H, Fukunaga K, Sato S, Kobayashi T, Dong T, Saheki T, Matsumoto M, Iwama H, Zhang H, Murao K. Role of ATP-binding cassette transporter A1 in suppressing lipid accumulation by glucagon-like peptide-1 agonist in hepatocytes. Mol Metab 2020; 34:16-26. [PMID: 32180556 PMCID: PMC6997505 DOI: 10.1016/j.molmet.2019.12.015] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2019] [Revised: 12/25/2019] [Accepted: 12/30/2019] [Indexed: 12/17/2022] Open
Abstract
Objective Adenosine triphosphate (ATP)-binding cassette transporter A1 (ABCA1) influences hepatic cholesterol transportation. Accumulation of hepatic cholesterol leads to fatty liver disease, which is improved by glucagon-like peptide 1 (GLP-1) in diabetes. Therefore, we analyzed the molecular mechanism in the regulation of hepatic ABCA1 by GLP-1 analogue exendin-4. Methods Hepatic ABCA1 expression and transcription were checked by western blotting, real-time polymerase chain reaction (PCR), and luciferase assay in HepG2 cells. Chromatin immunoprecipitation (ChIP) and site-directed mutagenesis were employed to determine transcriptional regulation of the ABCA1 gene. Prolactin regulatory element-binding (PREB)-transgenic mice were generated to access the effect of exendin-4 on improving lipid accumulation caused by a high-fat diet (HFD). Results Exendin-4 stimulated hepatic ABCA1 expression and transcription via the Ca2+/calmodulin (CaM)-dependent protein kinase kinase/CaM-dependent protein kinase IV (CaMKK/CaMKIV) pathway, whereas GLP-1 receptor antagonist exendin9-39 cancelled this effect. Therefore, exendin-4 decreased hepatic lipid content. ChIP showed that PREB could directly bind to the ABCA1 promoter, which was enhanced by exendin-4. Moreover, PREB stimulated ABCA1 promoter activity, and mutation of PREB-binding site in ABCA1 promoter cancelled exendin-4-enhanced ABCA1 promoter activity. Silencing of PREB attenuated the effect of exendin-4 and induced hepatic cholesterol accumulation. Blockade of CaMKK by STO-609 or siRNA cancelled the upregulation of ABCA1 and PREB induced by exendin-4. In vivo, exendin-4 or overexpression of PREB increased hepatic ABCA1 expression and decreased hepatic lipid accumulation and high plasma cholesterol caused by a HFD. Conclusions Our data shows that exendin-4 stimulates hepatic ABCA1 expression and decreases lipid accumulation by the CaMKK/CaMKIV/PREB pathway, suggesting that ABCA1 and PREB might be the therapeutic targets in fatty liver disease. The GLP-1R agonist exendin-4 suppressed lipid accumulation by upregulating ABCA1 expression in hepatocytes. Exendin-4 regulated the expression and transcription of hepatic ABCA1 via the CaMKK/CaMKIV/PREB pathway. Overexpression of PREB or exendin-4 protected mouse liver from fatty liver by upregulation of ABCA1.
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Affiliation(s)
- Jingya Lyu
- Department of Endocrinology and Metabolism, Faculty of Medicine, Kagawa University, 1750-1 Ikenobe, Miki-cho, Kita-gun, Kagawa, 761-0793, Japan; Department of Cell Biology, Jiangsu Key Laboratory of Stem Cell Research, Medical College of Soochow University, Ren Ai Road 199, Suzhou, 215123, China.
| | - Hitomi Imachi
- Department of Endocrinology and Metabolism, Faculty of Medicine, Kagawa University, 1750-1 Ikenobe, Miki-cho, Kita-gun, Kagawa, 761-0793, Japan
| | - Kensaku Fukunaga
- Department of Endocrinology and Metabolism, Faculty of Medicine, Kagawa University, 1750-1 Ikenobe, Miki-cho, Kita-gun, Kagawa, 761-0793, Japan
| | - Seisuke Sato
- Department of Endocrinology and Metabolism, Faculty of Medicine, Kagawa University, 1750-1 Ikenobe, Miki-cho, Kita-gun, Kagawa, 761-0793, Japan
| | - Toshihiro Kobayashi
- Department of Endocrinology and Metabolism, Faculty of Medicine, Kagawa University, 1750-1 Ikenobe, Miki-cho, Kita-gun, Kagawa, 761-0793, Japan
| | - Tao Dong
- Department of Endocrinology and Metabolism, Faculty of Medicine, Kagawa University, 1750-1 Ikenobe, Miki-cho, Kita-gun, Kagawa, 761-0793, Japan
| | - Takanobu Saheki
- Department of Endocrinology and Metabolism, Faculty of Medicine, Kagawa University, 1750-1 Ikenobe, Miki-cho, Kita-gun, Kagawa, 761-0793, Japan
| | - Mari Matsumoto
- Department of Endocrinology and Metabolism, Faculty of Medicine, Kagawa University, 1750-1 Ikenobe, Miki-cho, Kita-gun, Kagawa, 761-0793, Japan
| | - Hisakazu Iwama
- Life Science Research Center, Kagawa University, 1750-1 Ikenobe, Miki-cho, Kita-gun, Kagawa, 761-0793, Japan
| | - Huanxiang Zhang
- Department of Cell Biology, Jiangsu Key Laboratory of Stem Cell Research, Medical College of Soochow University, Ren Ai Road 199, Suzhou, 215123, China
| | - Koji Murao
- Department of Endocrinology and Metabolism, Faculty of Medicine, Kagawa University, 1750-1 Ikenobe, Miki-cho, Kita-gun, Kagawa, 761-0793, Japan
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Xuan NT, Toan NL, Mao CV, Vuong NB, Giang NT, Hoang NH. Regulation of dendritic cell function by A20 through high glucose-induced Akt2 signaling. J Recept Signal Transduct Res 2019; 39:434-441. [DOI: 10.1080/10799893.2019.1690511] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Nguyen Thi Xuan
- Institute of Genome Research, Vietnam Academy of Science and Technology, Hanoi, Vietnam
- Graduate University of Science and Technology, Vietnam Academy of Science and Technology, Hanoi, Vietnam
| | - Nguyen Linh Toan
- Department of Pathophysiology, Vietnam Military Medical University, Hanoi, Vietnam
| | - Can Van Mao
- Department of Pathophysiology, Vietnam Military Medical University, Hanoi, Vietnam
| | - Nguyen Ba Vuong
- 103 Military Hospital, Vietnam Military Medical University, Hanoi, Vietnam
| | | | - Nguyen Huy Hoang
- Institute of Genome Research, Vietnam Academy of Science and Technology, Hanoi, Vietnam
- Graduate University of Science and Technology, Vietnam Academy of Science and Technology, Hanoi, Vietnam
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Park JM, Kim MY, Kim TH, Min DK, Yang GE, Ahn YH. Prolactin regulatory element-binding (PREB) protein regulates hepatic glucose homeostasis. Biochim Biophys Acta Mol Basis Dis 2018; 1864:2097-2107. [PMID: 29601978 DOI: 10.1016/j.bbadis.2018.03.024] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Revised: 02/24/2018] [Accepted: 03/26/2018] [Indexed: 01/22/2023]
Abstract
Prolactin regulatory element-binding (PREB) protein is a transcription factor that regulates prolactin (PRL) gene expression. PRL, also known as luteotropic hormone or luteotropin, is well known for its role in producing milk. However, the role of PREB, in terms of hepatic glucose metabolism, is not well elucidated. Here, we observed expression of Preb in the mouse liver, in connection with glucose homeostasis. Morevoer, Preb was downregulated in db/db, ob/ob and high-fat diet-induced obese (DIO) mice, concurrent with upregulation of the liver genes glucose-6-phosphatase (G6pc) and phosphoenolpyruvate carboxykinase-1 (Pck). Administration of adenovirus-Preb (Ad-Preb) to db/db, ob/ob, and DIO mice diminished glucose, insulin, and pyruvate tolerance, which analogously, were impaired in normal (C57BL/6) mice knocked down for Preb, via infection with Ad-shPreb (anti-Preb RNA), indicating Preb to be a negative regulator of liver gluconeogenic genes. We further demonstrate that Preb negatively influences gluconeogenic gene expression, by directly binding to their promoters at a prolactin core-binding element (PCBE). A better understanding of Preb gene expression, during the pathogenesis of hepatic insulin resistance, could ultimately provide new avenues for therapies for metabolic syndrome, obesity, and type-2 diabetes mellitus, disorders whose worldwide incidences are increasing drastically.
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Affiliation(s)
- Joo-Man Park
- Department of Biochemistry and Molecular Biology, Brain Korea 21 Project for Medical Sciences, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea
| | - Mi-Young Kim
- Department of Biochemistry and Molecular Biology, Brain Korea 21 Project for Medical Sciences, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea
| | - Tae-Hyun Kim
- Department of Biochemistry and Molecular Biology, Brain Korea 21 Project for Medical Sciences, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea
| | - Dong-Kook Min
- Department of Biochemistry and Molecular Biology, Brain Korea 21 Project for Medical Sciences, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea
| | - Ga Eul Yang
- Department of Biochemistry and Molecular Biology, Brain Korea 21 Project for Medical Sciences, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea
| | - Yong-Ho Ahn
- Department of Biochemistry and Molecular Biology, Brain Korea 21 Project for Medical Sciences, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea.
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Zhang XZ, Imachi H, Lyu JY, Fukunaga K, Sato S, Ibata T, Kobayashi T, Yoshimoto T, Kikuchi F, Dong T, Murao K. Prolactin regulatory element-binding protein is involved in suppression of the adiponectin gene in vivo. J Endocrinol Invest 2017; 40:437-445. [PMID: 27914036 DOI: 10.1007/s40618-016-0589-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Accepted: 11/25/2016] [Indexed: 10/20/2022]
Abstract
PURPOSE Prolactin regulatory element-binding protein (PREB), a member of the WD-repeat protein family, has been recognized as a transcriptional factor that regulates prolactin promoter activity in the anterior pituitary of rats. PREB is expressed not only in the pituitary but also in various other tissues, including the adipose tissue. Previous studies have shown that PREB acts as a transcriptional regulator and suppresses the expression of the adiponectin gene in cultured 3T3L1 preadipocytes. The aim of this study was to further examine the potential role of PREB in adipose tissue in vivo. METHODS Transgenic mice that overexpressing PREB (PREB transgenic mice) were generated. Insulin resistance was evaluated in PREB transgenic mice using glucose and insulin tolerance tests. Adiponectin expression in the adipose tissue was examined by western blot analysis and quantitative polymerase chain reaction (qPCR). The expression levels of stearoyl-CoA desaturase (Scd) and adiponectin receptor 2(ADIPOR2) were quantified by qPCR. RESULTS Glucose and insulin tolerance tests revealed insulin resistance in PREB transgenic mice. Serum adiponectin and leptin concentrations were decreased. Adiponectin gene expression was decreased in the adipose tissue, which was confirmed by the downregulation of the adiponectin-dependent hepatic Scd gene and upregulation of the ADIPOR2 gene in the liver of PREB transgenic mice. We also found that pioglitazone, an agonist for the peroxisome proliferator-activated receptor-r, improved the insulin resistance in the PREB transgenic mice after a 10-day feeding period. CONCLUSIONS These results demonstrated that PREB might contribute to the regulation of adiponectin gene expression in vivo.
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Affiliation(s)
- X Z Zhang
- Department of Endocrinology and Metabolism, Faculty of Medicine, Kagawa University, 1750-1, ikenobe, Miki-CHO, 761-0793, Kagawa, Japan.
| | - H Imachi
- Department of Endocrinology and Metabolism, Faculty of Medicine, Kagawa University, 1750-1, ikenobe, Miki-CHO, 761-0793, Kagawa, Japan
| | - J Y Lyu
- Department of Endocrinology and Metabolism, Faculty of Medicine, Kagawa University, 1750-1, ikenobe, Miki-CHO, 761-0793, Kagawa, Japan
| | - K Fukunaga
- Department of Endocrinology and Metabolism, Faculty of Medicine, Kagawa University, 1750-1, ikenobe, Miki-CHO, 761-0793, Kagawa, Japan
| | - S Sato
- Department of Endocrinology and Metabolism, Faculty of Medicine, Kagawa University, 1750-1, ikenobe, Miki-CHO, 761-0793, Kagawa, Japan
| | - T Ibata
- Department of Endocrinology and Metabolism, Faculty of Medicine, Kagawa University, 1750-1, ikenobe, Miki-CHO, 761-0793, Kagawa, Japan
| | - T Kobayashi
- Department of Endocrinology and Metabolism, Faculty of Medicine, Kagawa University, 1750-1, ikenobe, Miki-CHO, 761-0793, Kagawa, Japan
| | - T Yoshimoto
- Department of Endocrinology and Metabolism, Faculty of Medicine, Kagawa University, 1750-1, ikenobe, Miki-CHO, 761-0793, Kagawa, Japan
| | - F Kikuchi
- Department of Endocrinology and Metabolism, Faculty of Medicine, Kagawa University, 1750-1, ikenobe, Miki-CHO, 761-0793, Kagawa, Japan
| | - T Dong
- Department of Endocrinology and Metabolism, Faculty of Medicine, Kagawa University, 1750-1, ikenobe, Miki-CHO, 761-0793, Kagawa, Japan
| | - K Murao
- Department of Endocrinology and Metabolism, Faculty of Medicine, Kagawa University, 1750-1, ikenobe, Miki-CHO, 761-0793, Kagawa, Japan
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Characterization and Expression of Turkey Prolactin Regulatory Element Binding in the Anterior Pituitary Gland and Pancreas During Embryogenesis. J Poult Sci 2016; 53:67-75. [PMID: 32908367 PMCID: PMC7477242 DOI: 10.2141/jpsa.0150091] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
The PRL regulatory element-binding (PREB) protein is a transcription factor that was originally cloned from the rat anterior pituitary gland and characterized as a regulator of the PRL promoter. It is also strongly expressed in several extrapituitary tissues; however, its functional role is not well understood to date. In this study, we aimed to clone and characterize the turkey PREB gene and investigate its mRNA expression in the anterior pituitary gland and pancreas during embryogenesis. Based on the conserved sequence of chicken and mammalian PREB cDNAs, a turkey PREB cDNA fragment was obtained, and after sequencing of the fragment, the 5′-and 3′-ends of mRNA were amplified and determined. To identify the PREB gene structure, polymerase chain reaction (PCR) amplification was performed. The turkey PREB gene consists of 9 exons and 8 introns, and it encodes a 411-amino-acid protein. The expression of PREB mRNA in the anterior pituitary gland was measured during embryogenesis. Levels of PREB mRNA significantly increased at embryonic day 22, with maximum levels being detected on day 25 of ontogeny, which correlated with similar changes in levels of PRL mRNA. The highest level of PREB mRNA was detected on day 19 in the pancreas. However, the highest level of insulin mRNA was detected at embryonic day 25. These results indicate that PREB may be involved in the expression of PRL mRNA in the anterior pituitary gland, whereas insulin mRNA may be expressed independently of the expression of PREB mRNA in the pancreas during embryogenesis.
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Miyai Y, Murao K, Imachi H, Li J, Nishiuchi Y, Masugata H, Iwama H, Kushida Y, Ishida T, Haba R. Exendin-4 regulates the expression of the ATP-binding cassette transporter A1 via transcriptional factor PREB in the pancreatic β cell line. J Endocrinol Invest 2011; 34:e268-74. [PMID: 21521937 DOI: 10.3275/7683] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND PRL regulatory element-binding (PREB) protein is a transcription factor that regulates insulin promoter activity in the rat anterior pituitary. The PREB protein is expressed not only in the anterior pituitary but also in pancreatic β cells. Previously, we have reported that PREB plays an important role in glucose-mediated insulin gene expression in pancreatic β cells. The ATP-binding cassette transporter A1 (ABCA1) in pancreatic β cells influences insulin secretion and glucose homeostasis. Exendin-4 (Ex-4), a longacting agonist of the glucagon-like peptide 1, stimulates ABCA1 expression in pancreatic β cells. AIMS In this study, we examined the role played by PREB in Ex-4-induced ABCA1 expression in pancreatic β cells. MATERIAL/SUBJECTS AND METHODS PREB mRNA and protein expression were evaluated in pancreatic β cell line (INS-1 cells) treated with Ex-4 (10 nM). RESULTS Ex-4 stimulated PREB protein and mRNA expression in INS-1 cells. PREB stimulated the activity of the luciferase reporter protein that was under the control of the ABCA1 promoter. Chromatin immunoprecipitation assay showed that PREB mediates its transcriptional activity by directly binding to the ABCA1 promoter region. Finally, we used small interfering RNA to inhibit PREB expression in the cells and demonstrated that the knockdown of PREB expression attenuated the effects of Ex-4 on ABCA1 expression. CONCLUSION PREB mediates Ex-4-stimulated transcription of the ABCA1 gene in pancreatic β cells.
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Affiliation(s)
- Y Miyai
- Department of diagnostic pathology, Kagawa University, Miki-cho, Kita-gun, Kagawa, Japan
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Chen K, Yu X, Murao K, Imachi H, Li J, Muraoka T, Masugata H, Zhang GX, Kobayashi R, Ishida T, Tokumitsu H. Exendin-4 regulates GLUT2 expression via the CaMKK/CaMKIV pathway in a pancreatic β-cell line. Metabolism 2011; 60:579-85. [PMID: 20598720 DOI: 10.1016/j.metabol.2010.06.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2010] [Revised: 05/19/2010] [Accepted: 06/01/2010] [Indexed: 11/17/2022]
Abstract
The GLUT2 glucose transporter plays an important role in glucose-induced insulin secretion in pancreatic β-cells by catalyzing the uptake of glucose into the cell. In this study, we investigated whether exendin-4, a long-acting agonist of glucagon-like peptide-1, mediates stimulatory effects on GLUT2 gene expression through the Ca²+/calmodulin (CaM)-dependent protein kinase IV (CaMKIV) cascade. GLUT2 expression was examined by real-time polymerase chain reaction, Western blot analysis, and a reporter gene assay in rat insulin-secreting INS-1 cells incubated with exendin-4. An increased expression level of GLUT2 protein was noted in response to increasing concentrations of exendin-4, with maximal induction at 10 nmol/L. Real-time polymerase chain reaction analysis similarly revealed a significant increase in the amount of GLUT2 messenger RNA by 10 nmol/L exendin-4. Exendin-4 also stimulated GLUT2 promoter activity in response to increasing exendin-4 concentrations, but failed to do so in the presence of STO-609, a CaMKK inhibitor. We also investigated the effect of the constitutively active form of CaMKK (CaMKKc) on GLUT2 promoter activity. The result is consistent with the observations that CaMKKc/CaMKIV enhanced or up-regulated GLUT2 promoter activity in INS-1 cells. Furthermore, exendin-4 induction of GLUT2 protein expression was significantly suppressed in the cells knocking down the CaMKIV. In summary, activation of the CaMKK/CaMKIV cascade might be required for exendin-4-induced GLUT2 gene transcription, indicating that exendin-4 plays an important role in insulin secretion in pancreatic β-cells.
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Affiliation(s)
- Ke Chen
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Faculty of Medicine, Kagawa University, 1750-1 Ikenobe Miki-CHO, Kagawa 761-0793, Japan
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Sugiyama Y, Murao K, Imachi H, Sueyoshi N, Ishida T, Kameshita I. Calcium/calmodulin-dependent protein kinase IV involvement in the pathophysiology of glucotoxicity in rat pancreatic β-cells. Metabolism 2011; 60:145-53. [PMID: 20423744 DOI: 10.1016/j.metabol.2010.03.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2010] [Revised: 03/08/2010] [Accepted: 03/22/2010] [Indexed: 01/24/2023]
Abstract
Glucotoxicity is a critical component of the pathophysiology of type 2 diabetes mellitus; however, the molecular mechanisms of glucotoxicity are still not fully understood. We have attempted to determine the protein kinases involved in glucotoxicity in pancreatic β-cells by the use of a new technique. Using Multi-PK antibodies, which are capable of detecting a wide variety of protein kinases, we analyzed the protein kinase that correlated with insulin synthesis in INS-1 cells under glucotoxic conditions. When expression patterns of protein kinases in INS-1 cells were analyzed by Western blotting with Multi-PK antibodies, a kinase of 63 kd was significantly reduced concomitant with the decrease of insulin secretion under glucotoxic conditions. To identify the 63-kd kinase, we used a unique 2-dimensional gel electrophoretic technique and MicroRotofor (Bio-Rad Laboratories, Tokyo, Japan) electrophoresis. From the molecular size of a native kinase/cyanogen bromide fragment and pI value, the 63-kd protein kinase was deduced to be CaMKIV. This was confirmed by Western blotting analysis using anti-CaMKIV antibodies. The decreased CaMKIV levels under glucotoxic conditions recovered to original levels after changing the medium to a normal glucose concentration. Recombinant CaMKIV was degraded in a Ca²+-dependent manner by incubation with cell lysates from INS-1 cells under glucotoxic conditions, and degradation was protected by calpain inhibitor. Furthermore, CaMKIV was reduced in the pancreatic islets of diabetic Otsuka Long-Evans Tokushima fatty rats, whereas that of nondiabetic Long-Evans Tokushima Otsuka rats was not. This study suggests that the abnormal regulation of CaMKIV is a component of β-cell dysfunction caused by high glucose.
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Affiliation(s)
- Yasunori Sugiyama
- Department of Life Sciences, Faculty of Agriculture, Kagawa University, 2393 Ikenobe Miki-cho, Kita-gun, Kagawa 761-0795, Japan
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Yuan ZQ, Zhao BS, Zhang JY, Zhang SC. Expression pattern of DjPreb gene during the planarian Dugesia japonica embryonic development. Mol Biol 2010. [DOI: 10.1134/s0026893310040114] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Yu X, Murao K, Imachi H, Li J, Nishiuchi T, Dobashi H, Hosomi N, Masugata H, Zhang GX, Iwama H, Ishida T. The transcription factor prolactin regulatory element-binding protein mediates prolactin transcription induced by thyrotropin-releasing hormone in GH3 cells. Endocrine 2010; 38:53-9. [PMID: 20960102 DOI: 10.1007/s12020-010-9343-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2009] [Accepted: 04/19/2010] [Indexed: 11/24/2022]
Abstract
The prolactin regulatory element-binding protein (PREB) is a transcription factor that regulates prolactin (PRL) promoter activity in the rat anterior pituitary. PRL gene expression and secretion are regulated by various hormones and growth factors, including dopamine, epidermal growth factor, and thyrotropin-releasing hormone (TRH). We examined the effect of TRH on PREB expression in pituitary cells. Western blots probed with a PREB-specific antiserum showed that the relative abundance of PREB in GH3 cells increased on treatment with TRH in a dose-dependent manner. The relative abundance of PREB mRNA also increased in a dose-dependent manner after treatment with TRH. TRH induced the expression of the luciferase reporter protein under the PREB promoter control. We used inhibitors of certain signal transduction pathways to show that TRH-induced PREB induction is sensitive to the protein kinase A (PKA) inhibitor. TRH stimulated the activity of the wild-type PRL promoter, whereas mutation of the PREB core-binding element on the PRL promoter reduced this ability. In summary, we have shown that TRH stimulated PREB expression in GH3 cells via the PKA pathway. PREB can function as a transcriptional regulator of PRL promoter activity and might be involved in TRH-induced PRL gene transcription.
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Affiliation(s)
- Xiao Yu
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Faculty of Medicine, Kagawa University, Kita-gun, Kagawa, Japan
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Muraoka T, Murao K, Imachi H, Yu X, Li J, Wong NC, Ishida T. PREB regulates transcription of pancreatic glucokinase in response to glucose and cAMP. J Cell Mol Med 2010; 13:2386-2395. [PMID: 19267880 DOI: 10.1111/j.1582-4934.2008.00469.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
Prolactin regulatory element binding (PREB) is a transcription factor that regulates prolactin promoter activity in rat anterior pituitary. The PREB protein is not only expressed in the anterior pituitary but also in the pancreas. We have recently reported that in pancreatic beta-cells, PREB regulates the transcription of the insulin gene in response to glucose stimulation. In the current study, we have examined the role of PREB in regulating glucokinase (GK) in pancreatic beta-cells. To analyse the effects of PREB on GK gene transcription, we employed a reporter gene assay. In the cells expressing or with knocked down PREB, GK expression was determined. GK expression was regulated by glucose and cAMP, and both glucose and cAMP stimulated the expression of PREB in a dose-dependent manner. Conversely, overexpression of PREB using a PREB-expressing adenovirus increased the expression of the GK protein. GK enzymatic activity was also significantly increased in the cells that stably expressed PREB. In addition, PREB induced GK promoter activity. Chromatin immunoprecipitation (ChIP) analyses showed that PREB mediated its transcriptional effect by binding to the PREB-responsive cis-element of the GK promoter. Finally, we used siRNA to inhibit PREB expression in cells and demonstrated that the knockdown of PREB attenuated the effects of glucose and cAMP on GK expression. Our data show that in pancreatic -cells, PREB regulates the transcription of the GK gene in response to glucose and cAMP.
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Affiliation(s)
- Tomie Muraoka
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Faculty of Medicine, Kagawa University, Kita-gun, Kagawa, Japan
| | - Koji Murao
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Faculty of Medicine, Kagawa University, Kita-gun, Kagawa, Japan
| | - Hitomi Imachi
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Faculty of Medicine, Kagawa University, Kita-gun, Kagawa, Japan
| | - Xiao Yu
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Faculty of Medicine, Kagawa University, Kita-gun, Kagawa, Japan
| | - Junhua Li
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Faculty of Medicine, Kagawa University, Kita-gun, Kagawa, Japan
| | - Norman Cw Wong
- Departments of Medicine and Biochemistry & Molecular Biology, Faculty of Medicine, University of Calgary, Health Sciences Center, Calgary, Alberta, Canada
| | - Toshihiko Ishida
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Faculty of Medicine, Kagawa University, Kita-gun, Kagawa, Japan
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Nishiuchi Y, Murao K, Imachi H, Nishiuchi T, Iwama H, Ishida T. Transcriptional factor prolactin regulatory element-binding protein-mediated gene transcription of ABCA1 via 3',5'-cyclic adenosine-5'-monophosphate. Atherosclerosis 2010; 212:418-25. [PMID: 20643408 DOI: 10.1016/j.atherosclerosis.2010.06.024] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2009] [Revised: 06/10/2010] [Accepted: 06/14/2010] [Indexed: 11/29/2022]
Abstract
OBJECTIVE Prolactin regulatory element-binding (PREB) protein is a transcription factor that regulates prolactin promoter activity in the rat anterior pituitary. The PREB protein is not only expressed in the anterior pituitary but also in the cardiovascular system, including vascular smooth muscle cells (SMCs). However, the role of PREB in SMCs is not clearly understood. The ATP-binding cassette transporter A1 (ABCA1) regulates lipid efflux from peripheral cells to apolipoproteins. In the present study, we have examined the role of PREB in regulating ABCA1 expression mediated by 3',5'-cyclic adenosine-5'-monophosphate (cAMP). METHODS AND RESULTS PREB was expressed in the rats SMC line CRL-2018. ABCA1 expression was found to be regulated by cAMP, which stimulated the expression of PREB in a dose-dependent manner. Conversely, over-expression of PREB, which was induced by a PREB-expressing adenovirus, increased the expression of the ABCA1 protein in CRL-2018 cells. In addition, PREB stimulated the activity of the luciferase reporter protein that was under the control of the ABCA1 promoter. Chromatin immunoprecipitation assay showed that PREB mediates its transcriptional activity by directly binding to the ABCA1 promoter region. Finally, we used siRNA to inhibit PREB expression in the cells and demonstrated that the knockdown of PREB expression attenuated the effects of cAMP on ABCA1 expression. CONCLUSIONS In summary, our data showed that PREB regulates the cAMP-mediated transcription of the ABCA1 gene in vascular SMCs.
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Affiliation(s)
- Yukiko Nishiuchi
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Faculty of Medicine, Kagawa University, 1750-1 Ikenobe, Miki-cho, Kita-gun, Kagawa 761-0793, Japan
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Li J, Murao K, Imachi H, Yu X, Muraoka T, Kim JB, Ishida T. Prolactin regulatory element-binding protein involved in cAMP-mediated suppression of adiponectin gene. J Cell Mol Med 2010; 14:1294-302. [PMID: 19382911 PMCID: PMC3828846 DOI: 10.1111/j.1582-4934.2009.00752.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2008] [Accepted: 03/04/2009] [Indexed: 02/02/2023] Open
Abstract
Adiponectin (ApN) has several protective effects against diabetes and atherosclerosis. However, the detailed mechanisms of the regulation of the ApN gene have not yet been clarified. Prolactin regulatory element-binding (PREB) protein has been identified as a factor that regulates insulin gene expression in the pancreas. PREB is located not only in the pancreas but also in adipose tissue; however, its role in adipose tissue is not known. To analyse the effects of PREB on ApN gene transcription, we employed a reporter gene assay and electrophoretic mobility shift assay (EMSA). In the cells expressing or knocking down the PREB, ApN expression was determined. PREB was located mainly in the nuclei of adipose tissue and its cell line, 3T3-L1 cells. The nuclear extract contained ApN promoter-binding activity that was super-shifted by PREB antiserum in EMSA studies. In the 3T3-L1 cells, the co-expression of PREB and the ApN promoter inhibited the activity of the latter. The addition of cAMP to the cells increased PREB expression in a dose-dependent manner. A deletional analysis of the ApN promoter showed that the PREB-responsive cis-element in the ApN promoter mediated the transcriptional effect of PREB, whereas a mutant of this motif in the ApN promoter abrogated the effect of PREB, as well as that of cAMP. Furthermore, cells expressing or knocking down PREB exhibited decreased and increased ApN expression, respectively. These results demonstrate that PREB may contribute to the regulation of ApN gene transcription, in response to cAMP activation in adipocytes.
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Affiliation(s)
- Junhua Li
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Faculty of Medicine, Kagawa University1750-1 Ikenobe Miki-CHO, Kita-gun, Kagawa, Japan
| | - Koji Murao
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Faculty of Medicine, Kagawa University1750-1 Ikenobe Miki-CHO, Kita-gun, Kagawa, Japan
| | - Hitomi Imachi
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Faculty of Medicine, Kagawa University1750-1 Ikenobe Miki-CHO, Kita-gun, Kagawa, Japan
| | - Xiao Yu
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Faculty of Medicine, Kagawa University1750-1 Ikenobe Miki-CHO, Kita-gun, Kagawa, Japan
| | - Tomie Muraoka
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Faculty of Medicine, Kagawa University1750-1 Ikenobe Miki-CHO, Kita-gun, Kagawa, Japan
| | - Jae Bum Kim
- Department of Biological Sciences, Seoul National UniversitySan 56-1, Sillim-Dong, Kwanak-Gu, Seoul, Korea
| | - Toshihiko Ishida
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Faculty of Medicine, Kagawa University1750-1 Ikenobe Miki-CHO, Kita-gun, Kagawa, Japan
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Yuan ZQ, Zhao BS, Zhang JY, Zhang SC. Characterization and expression of DjPreb gene in the planarian Dugesia japonica. Mol Biol 2010. [DOI: 10.1134/s0026893310010024] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Murao K, Imachi H, Yu X, Muraoka T, Hosami N, Dobashi H, Ishida T. The transcriptional factor PREB mediates MCP-1 transcription induced by cytokines in human vascular endothelial cells. Atherosclerosis 2009; 207:45-50. [DOI: 10.1016/j.atherosclerosis.2009.03.051] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2008] [Revised: 03/31/2009] [Accepted: 03/31/2009] [Indexed: 11/30/2022]
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Murao K, Li J, Imachi H, Muraoka T, Masugata H, Zhang GX, Kobayashi R, Ishida T, Tokumitsu H. Exendin-4 regulates glucokinase expression by CaMKK/CaMKIV pathway in pancreatic beta-cell line. Diabetes Obes Metab 2009; 11:939-46. [PMID: 19486109 DOI: 10.1111/j.1463-1326.2009.01067.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
AIM Glucokinase (GK) in pancreatic beta cells is thought to be involved in insulin secretion and glucose homeostasis. This study investigates whether the long-acting agonist of the glucagon-like peptide 1, namely exendin-4, mediates stimulatory effects on GK gene expression through the Ca(2+)/calmodulin (CaM)-dependent protein kinase (CaMK) cascade. METHODS GK expression was examined by real-time PCR, western blot analysis and reporter gene assay in rat insulin-secreting INS-1 cells incubated with exendin-4. CaMKIV activity was assessed by detection of activation loop phosphorylation (Thr(196)) of CaMKIV. We investigated the effect of the constitutively active form (CaMKIVc) of CaMKIV on GK promoter activity. RESULTS Increased expression level of GK protein was noted in response to rising concentrations of exendin-4 with maximum induction at 10 nM. Real-time PCR analysis showed a significant increase in the amount of GK mRNA in response to rising concentrations of exendin-4. Exendin-4 also stimulated GK promoter activity but failed to do so in the presence of STO-609, a CaMKK inhibitor. This result is consistent with the observations that the upregulation of CaMKIV phosphorylation (at Thr(196)) peaked after 15 min of exposure to exendin-4 and that CaMKIVc enhanced or upregulated GK promoter activity in INS-1 cells. Furthermore, STO-609 significantly suppressed the exendin-4 - upregulated the expression of the GK protein. CONCLUSION Activation of the CaMKK/CaMKIV cascade might be required for exendin-4-induced GK gene transcription, indicating that exendin-4 plays an important role in insulin secretion in pancreatic beta cells.
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Affiliation(s)
- K Murao
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Kagawa University, 1750-1 Ikenobe, Miki-cho, Kita-gun, Kagawa 761-0793, Japan.
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Murao K, Imachi H, Yu X, Cao WM, Muraoka T, Dobashi H, Hosomi N, Haba R, Iwama H, Ishida T. The transcriptional factor prolactin regulatory element-binding protein mediates the gene transcription of adrenal scavenger receptor class B type I via 3',5'-cyclic adenosine 5'-monophosphate. Endocrinology 2008; 149:6103-12. [PMID: 18755803 DOI: 10.1210/en.2008-0380] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Prolactin regulatory element-binding (PREB) protein is a transcription factor that regulates prolactin promoter activity in the rat anterior pituitary. The PREB protein is not only expressed in the anterior pituitary but also in the adrenal gland. However, the role of PREB in the adrenal gland is not clearly understood. Scavenger receptor class B type I (SR-BI) is a receptor for high-density lipoprotein that mediates the cellular uptake of high-density lipoprotein-cholesteryl ester and is a major route for cholesterol delivery to the steroidogenic pathway in the adrenal gland. In the present study, we have examined the role of PREB in regulating SR-BI. SR-BI expression was found to be regulated by cAMP, which stimulated the expression of PREB in a dose-dependent manner. Conversely, overexpression of PREB using a PREB-expressing adenovirus increased the expression of the SR-BI protein in the adrenocortical cell line Y-1. In addition, PREB induced the expression of the luciferase reporter protein that was under the control of the SR-BI promoter. EMSA showed that PREB mediates its transcriptional effect by binding to the PREB-responsive cis-element of the SR-BI promoter. Finally, we used small interfering RNA to inhibit PREB expression in the Y-1 cells and demonstrated that the knockdown of PREB expression attenuated the effects of cAMP on SR-BI expression. In summary, our data showed that in the adrenal gland, PREB regulates the transcription of the SR-BI gene via cAMP.
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Affiliation(s)
- Koji Murao
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Faculty of Medicine, Kagawa University, 1750-1 Ikenobe Miki-CHO, Kita-gun, Kagawa 761-0793, Japan.
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Imachi H, Murao K, Cao WM, Muraoka T, Nishiuchi T, Dobashi H, Hosomi N, Iwama H, Ishida T. The prolactin regulatory element-binding regulates of the 11beta-hydroxylase gene. Biochem Biophys Res Commun 2008; 376:531-5. [PMID: 18801336 DOI: 10.1016/j.bbrc.2008.09.027] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2008] [Accepted: 09/06/2008] [Indexed: 11/29/2022]
Abstract
Prolactin regulatory element-binding (PREB) protein is a transcription factor not only in pituitary but also adrenal gland. Steroid 11beta-hydroxylase (CYP11B1), a member of the cytochrome p-450 superfamily, is responsible for the last step of glucocorticoid biosynthesis in the adrenal cortices of many kinds of animals. In the present study, we have examined the role of PREB in regulating CYP11B1. CYP11B1 expression was found to be regulated by cAMP, which stimulated the expression of PREB. In addition, PREB induced the expression of the luciferase reporter protein that was under the control of the CYP11B1 promoter. Electrophoretic mobility shift analysis (EMSA) showed that PREB mediates its transcriptional effect by binding to the PREB-responsive cis-element (PRCE) of the CYP11B1 promoter. The knockdown of PREB expression attenuated the effects of cAMP on CYP11B1 expression. In summary, our data showed that in the adrenal gland, PREB regulates the transcription of the CYP11B1 gene via cAMP.
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Affiliation(s)
- Hitomi Imachi
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Faculty of Medicine, Kagawa University, 1750-1 Ikenobe Miki-CHO, Kita-gun, Kagawa 761-0793, Japan
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Bibliography. Current world literature. Diabetes and the endocrine pancreas II. Curr Opin Endocrinol Diabetes Obes 2007; 14:329-57. [PMID: 17940461 DOI: 10.1097/med.0b013e3282c3a898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Yoshida K, Murao K, Imachi H, Cao WM, Yu X, Li J, Ahmed RAM, Kitanaka N, Wong NCW, Unterman TG, Magnuson MA, Ishida T. Pancreatic glucokinase is activated by insulin-like growth factor-I. Endocrinology 2007; 148:2904-13. [PMID: 17317782 DOI: 10.1210/en.2006-1149] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Glucokinase (GK) plays a key role in the regulation of glucose use and glucose-stimulated insulin secretion in pancreatic islet cells. Gene targeting of the IGF-I receptor down-regulated pancreatic islet GK activity. That finding prompted us to examine the potential mechanism that may control GK gene activity using an islet cell line, INS-1, known to express IGF-I receptor. Exposure of these cells to IGF-I induced GK protein expression and activity of the enzyme in a dose-dependent manner. In addition, IGF-I induced activity of a reporter construct containing the GK promoter in parallel with the effect on endogenous GK mRNA levels. The stimulatory effect of IGF-I on GK promoter activity was abrogated by wortmannin and LY294002, specific inhibitors of phosphatidylinositol 3-kinase. Exposure of cells to IGF-I elicited a rapid phosphorylation of Akt and FoxO1, a known target of Akt signaling. Constitutively active Akt stimulates the activity of the GK promoter, and a dominant-negative mutant of Akt or mutagenesis of a FoxO1 response element in the GK promoter abolished the ability of IGF-I to stimulate the promoter activity. Furthermore, cell knockdown of FoxO1 with small interfering RNA disrupted the effect of IGF-I on GK expression. These results demonstrate that the phosphatidylinositol 3-kinase/Akt/FoxO1 pathway contributes to the regulation of GK gene expression in response to IGF-I stimulation.
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Affiliation(s)
- Kazuya Yoshida
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Faculty of Medicine, Kagawa University, 1750-1 Miki-cho, Kita-gun, Kagawa 761-0793, Japan
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Bibliography. Current world literature. Diabetes and the endocrine pancreas. Curr Opin Endocrinol Diabetes Obes 2007; 14:170-96. [PMID: 17940437 DOI: 10.1097/med.0b013e3280d5f7e9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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