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Lin YC, Liao YJ, Lee YH, Tseng SF, Liu JY, Chen YS, Shui HA, Lin FZ, Lin KH, Chen YC, Tsai MC, Sytwu HK, Wang CC, Chuang YP. Staphylococcal phosphatidylinositol-specific phospholipase C potentiates lung injury via complement sensitisation. Cell Microbiol 2019; 21:e13085. [PMID: 31290210 DOI: 10.1111/cmi.13085] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [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: 11/23/2018] [Revised: 07/02/2019] [Accepted: 07/03/2019] [Indexed: 11/29/2022]
Abstract
Staphylococcus aureus is frequently isolated from patients with community-acquired pneumonia and acute respiratory distress syndrome (ARDS). ARDS is associated with staphylococcal phosphatidylinositol-specific phospholipase C (PI-PLC); however, the role of PI-PLC in the pathogenesis and progression of ARDS remains unknown. Here, we showed that recombinant staphylococcal PI-PLC possesses enzyme activity that causes shedding of glycosylphosphatidylinositol-anchored CD55 and CD59 from human umbilical vein endothelial cell surfaces and triggers cell lysis via complement activity. Intranasal infection with PI-PLC-positive S. aureus resulted in greater neutrophil infiltration and increased pulmonary oedema compared with a plc-isogenic mutant. Although indistinguishable proinflammatory genes were induced, the wild-type strain activated higher levels of C5a in lung tissue accompanied by elevated albumin instillation and increased lactate dehydrogenase release in bronchoalveolar lavage fluid compared with the plc- mutant. Following treatment with cobra venom factor to deplete complement, the wild-type strain with PI-PLC showed a reduced ability to trigger pulmonary permeability and tissue damage. PI-PLC-positive S. aureus induced the formation of membrane attack complex, mainly on type II pneumocytes, and reduced the level of CD55/CD59, indicating the importance of complement regulation in pulmonary injury. In conclusion, S. aureus PI-PLC sensitised tissue to complement activation leading to more severe tissue damage, increased pulmonary oedema, and ARDS progression.
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Affiliation(s)
- Yu-Chun Lin
- Department of Pathology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.,Department of Graduate Institute of Pathology and Parasitology, National Defense Medical Center, Taipei, Taiwan
| | - Yu-Jou Liao
- Department and Graduate Institute of Microbiology and Immunology, National Defense Medical Center, Taipei, Taiwan
| | - Ying-Hsuan Lee
- Department and Graduate Institute of Microbiology and Immunology, National Defense Medical Center, Taipei, Taiwan
| | - Shun-Fu Tseng
- Department and Graduate Institute of Microbiology and Immunology, National Defense Medical Center, Taipei, Taiwan
| | - Jah-Yao Liu
- Department of Obstetrics and Gynecology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Ying-Sheng Chen
- Division of Infectious Diseases, Department of Internal Medicine, Cardinal Tien Hospital, New Taipei City, Taiwan
| | - Hao-Ai Shui
- Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei, Taiwan
| | - Feng-Zhi Lin
- Graduate Institute of Life Sciences, National Defense Medical Center and Academia Sinica, Taipei, Taiwan
| | - Kai-Hsuan Lin
- Department and Graduate Institute of Microbiology and Immunology, National Defense Medical Center, Taipei, Taiwan
| | - Yao-Chang Chen
- Department of Biomedical Engineering and Institute of Physiology, National Defense Medical Center, Taipei, Taiwan
| | - Min-Chien Tsai
- Department of Physiology and Biophysics, Graduate Institute of Physiology, National Defense Medical Center, Taipei, Taiwan
| | - Huey-Kang Sytwu
- Department and Graduate Institute of Microbiology and Immunology, National Defense Medical Center, Taipei, Taiwan.,National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Miaoli, Taiwan
| | - Chih-Chien Wang
- Department of Pediatrics, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Yi-Ping Chuang
- Department and Graduate Institute of Microbiology and Immunology, National Defense Medical Center, Taipei, Taiwan
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2
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Dai MS, Lo HC, Chen LJ, Tseng SF. Prognostic significance of tartrate-resistant acid phosphatase expression in breast cancer. J Clin Oncol 2019. [DOI: 10.1200/jco.2019.37.15_suppl.e12594] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
e12594 Background: Tartrate-resistant acid phosphatase (TRAP) is a metalloproteinase-like protein that is expressed in several primary and metastatic tumors, and its expression is positively correlated with the oncogenic process. Tartrate-resistant acid phosphatase is also a novel product of activated macrophage. We have previously demonstrated the clinical significance of TRAP expression in tumor-infiltrating macrophages and serum TRAP in patients with metastatic breast cancer (BC). Therefore, TRAP protein can potentially be a predictive and prognostic marker to evaluate disease progression and therapeutic response in breast cancer patients with bone metastasis. We aim to investigate the role of TRAP expression in breast cancer metastasis and survival. Methods: RNA-seq expression data were obtained from The Cancer Genome Atlas (TCGA) database. Estrogen receptor (ER)-positive, human epidermal growth factor receptor-2 (HER2)-negative, and TNBC subtypes were included in the analyses. The TRAP-overexpressed and -silenced breast cancer cells (MCF7, 4T1, MDA-MB-231) were used for validation. Survival data was also retrieved from the TCGA database to verify the prognostic biomarker. Results: Through TCGA database analysis, we found that TRAP expression correlated to the Ki-67 expression indicating the cancer cell proliferating activity. Additionally, TRAP expression positively correlated with mesenchymal markers (SNAIL, CDH1, MMP9, Fibronectin), and negatively correlated with epithelial markers (SMAD2, SOX10), implying that the TRAP expression is related to the breast cancer Epithelial-Mesenchymal-Transition process. This phenomenon was validated in TRAP-altered cell and confirmed inferior survival with TRAP-expressed breast cancer patients in TCGA database. Conclusions: Combining clinical TCGA data and cell-based analyses showed that TRAP expression was significantly associated with breast cancer proliferating activity, metastatic potential, and inferior survival. TRAP serves as a breast cancer prognostic biomarker and can be considered as a therapeutic target. Further investigation is warranted.
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Affiliation(s)
| | - Hao-Chan Lo
- Tri-Service General Hospital, Taipei, Taiwan
| | - Li-Jia Chen
- Tri-Service General Hospital, Taipei, Taiwan
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3
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Hsu CF, Hsiao CH, Tseng SF, Chen JR, Liao YJ, Chen SJ, Lin CS, Sytwu HK, Chuang YP. PrtA immunization fails to protect against pulmonary and invasive infection by Streptococcus pneumoniae. Respir Res 2018; 19:187. [PMID: 30253765 PMCID: PMC6157060 DOI: 10.1186/s12931-018-0895-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [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: 06/08/2018] [Accepted: 09/17/2018] [Indexed: 12/27/2022] Open
Abstract
Background Streptococcus pneumoniae is a respiratory pathogen causing severe lung infection that may lead to complications such as bacteremia. Current polysaccharide vaccines have limited serotype coverage and therefore cannot provide maximal and long-term protection. Global efforts are being made to develop a conserved protein vaccine candidate. PrtA, a pneumococcal surface protein, was identified by screening a pneumococcal genomic expression library using convalescent patient serum. The prtA gene is prevalent and conserved among S. pneumoniae strains. Its protective efficacy, however, has not been described. Mucosal immunization could sensitize both local and systemic immunity, which would be an ideal scenario for preventing S. pneumoniae infection. Methods We immunized BALB/c mice intranasally with a combination of a PrtA fragment (amino acids 144–1041) and Th17 potentiated adjuvant, curdlan. We then measured the T-cell and antibody responses. The protective efficacy conferred to the immunized mice was further evaluated using a murine model of acute pneumococcal pneumonia and pneumococcal bacteremia. Results There was a profound antigen-specific IL-17A and IFN-γ response in PrtA-immunized mice compared with that of adjuvant control group. Even though PrtA-specific IgG and IgA titer in sera was elevated in immunized mice, only a moderate IgA response was observed in the bronchoalveolar lavage fluid. The PrtA-immunized antisera facilitated the activated murine macrophage, RAW264.7, to opsonophagocytose S. pneumoniae D39 strain; however, PrtA-specific immunoglobulins bound to pneumococcal surfaces with a limited potency. Finally, PrtA-induced immune reactions failed to protect mice against S. pneumoniae-induced acute pneumonia and bacterial propagation through the blood. Conclusions Immunization with recombinant PrtA combined with curdlan produced antigen-specific antibodies and elicited IL-17A response. However, it failed to protect the mice against S. pneumoniae-induced infection. Electronic supplementary material The online version of this article (10.1186/s12931-018-0895-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Chen-Fang Hsu
- Department of Pediatrics, Chi Mei Medical Center, Tainan, Taiwan.,Taipei Medical University, Taipei, Taiwan.,Kaohsiung Medical University, Kaohsiung, Taiwan.,Chung Shan Medical University, Taichung, Taiwan
| | - Chen-Hao Hsiao
- Cheng Hsin General Hospital, Taipei, Taiwan.,Genome and Systems Biology Degree Program, National Taiwan University and Academia Sinica, Taipei, Taiwan
| | - Shun-Fu Tseng
- Department and Graduate Institute of Microbiology and Immunology, National Defense Medical Center, Taipei, Taiwan
| | - Jian-Ru Chen
- Department and Graduate Institute of Microbiology and Immunology, National Defense Medical Center, Taipei, Taiwan
| | - Yu-Jou Liao
- Department and Graduate Institute of Microbiology and Immunology, National Defense Medical Center, Taipei, Taiwan
| | - Sy-Jou Chen
- Department of Emergency Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.,Graduate Institute of Injury Prevention and Control, College of Public Health and Nutrition, Taipei Medical University, Taipei, Taiwan
| | - Chin-Sheng Lin
- Division of Cardiology, Department of Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Huey-Kang Sytwu
- Department and Graduate Institute of Microbiology and Immunology, National Defense Medical Center, Taipei, Taiwan.,National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Miaoli, Taiwan
| | - Yi-Ping Chuang
- Department and Graduate Institute of Microbiology and Immunology, National Defense Medical Center, Taipei, Taiwan.
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4
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Yang CW, Tseng SF, Yu CJ, Chung CY, Chang CY, Pobiega S, Teng SC. Telomere shortening triggers a feedback loop to enhance end protection. Nucleic Acids Res 2017; 45:8314-8328. [PMID: 28575419 PMCID: PMC5737367 DOI: 10.1093/nar/gkx503] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [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: 12/18/2016] [Accepted: 05/26/2017] [Indexed: 01/20/2023] Open
Abstract
Telomere homeostasis is controlled by both telomerase machinery and end protection. Telomere shortening induces DNA damage sensing kinases ATM/ATR for telomerase recruitment. Yet, whether telomere shortening also governs end protection is poorly understood. Here we discover that yeast ATM/ATR controls end protection. Rap1 is phosphorylated by Tel1 and Mec1 kinases at serine 731, and this regulation is stimulated by DNA damage and telomere shortening. Compromised Rap1 phosphorylation hampers the interaction between Rap1 and its interacting partner Rif1, which thereby disturbs the end protection. As expected, reduction of Rap1–Rif1 association impairs telomere length regulation and increases telomere–telomere recombination. These results indicate that ATM/ATR DNA damage checkpoint signal contributes to telomere protection by strengthening the Rap1–Rif1 interaction at short telomeres, and the checkpoint signal oversees both telomerase recruitment and end capping pathways to maintain telomere homeostasis.
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Affiliation(s)
- Chia-Wei Yang
- Department of Microbiology, College of Medicine, National Taiwan University, Taipei 100, Taiwan
| | - Shun-Fu Tseng
- Department and Graduate Institute of Microbiology and Immunology, National Defense Medical Center, Taipei 100, Taiwan
| | - Chia-Jung Yu
- Department of Cell and Molecular Biology, College of Medicine, Chang Gung University, Tao-Yuan 333, Taiwan.,Department of Thoracic Medicine, Chang Gung Memorial Hospital, Linkou, Tao-Yuan 333, Taiwan
| | - Chia-Yu Chung
- Department of Microbiology, College of Medicine, National Taiwan University, Taipei 100, Taiwan
| | - Cheng-Yen Chang
- Department of Microbiology, College of Medicine, National Taiwan University, Taipei 100, Taiwan
| | - Sabrina Pobiega
- INSERM UMR 967, Institut de Biologie François Jacob, CEA Paris-Saclay, 92265 Fontenay-aux-roses, France
| | - Shu-Chun Teng
- Department of Microbiology, College of Medicine, National Taiwan University, Taipei 100, Taiwan
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5
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Chang CJ, Lin CS, Lu CC, Martel J, Ko YF, Ojcius DM, Tseng SF, Wu TR, Chen YYM, Young JD, Lai HC. Corrigendum: Ganoderma lucidum reduces obesity in mice by modulating the composition of the gut microbiota. Nat Commun 2017; 8:16130. [PMID: 28695905 PMCID: PMC5508223 DOI: 10.1038/ncomms16130] [Citation(s) in RCA: 75] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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6
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Chang YL, Tseng SF, Huang YC, Shen ZJ, Hsu PH, Hsieh MH, Yang CW, Tognetti S, Canal B, Subirana L, Wang CW, Chen HT, Lin CY, Posas F, Teng SC. Yeast Cip1 is activated by environmental stress to inhibit Cdk1-G1 cyclins via Mcm1 and Msn2/4. Nat Commun 2017; 8:56. [PMID: 28676626 PMCID: PMC5496861 DOI: 10.1038/s41467-017-00080-y] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [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: 05/13/2016] [Accepted: 06/01/2017] [Indexed: 12/20/2022] Open
Abstract
Upon environmental changes, proliferating cells delay cell cycle to prevent further damage accumulation. Yeast Cip1 is a Cdk1 and Cln2-associated protein. However, the function and regulation of Cip1 are still poorly understood. Here we report that Cip1 expression is co-regulated by the cell-cycle-mediated factor Mcm1 and the stress-mediated factors Msn2/4. Overexpression of Cip1 arrests cell cycle through inhibition of Cdk1–G1 cyclin complexes at G1 stage and the stress-activated protein kinase-dependent Cip1 T65, T69, and T73 phosphorylation may strengthen the Cip1and Cdk1–G1 cyclin interaction. Cip1 accumulation mainly targets Cdk1–Cln3 complex to prevent Whi5 phosphorylation and inhibit early G1 progression. Under osmotic stress, Cip1 expression triggers transient G1 delay which plays a functionally redundant role with another hyperosmolar activated CKI, Sic1. These findings indicate that Cip1 functions similarly to mammalian p21 as a stress-induced CDK inhibitor to decelerate cell cycle through G1 cyclins to cope with environmental stresses. A G1 cell cycle regulatory kinase Cip1 has been identified in budding yeast but how this is regulated is unclear. Here the authors identify cell cycle (Mcm1) and stress-mediated (Msn 2/4) transcription factors as regulating Cip1, causing stress induced CDK inhibition and delay in cell cycle progression.
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Affiliation(s)
- Ya-Lan Chang
- Department of Microbiology, College of Medicine, National Taiwan University, Taipei, 10051, Taiwan
| | - Shun-Fu Tseng
- Department of Microbiology, College of Medicine, National Taiwan University, Taipei, 10051, Taiwan.,Department and Graduate Institute of Microbiology and Immunology, National Defense Medical Center, Taipei, 11490, Taiwan
| | - Yu-Ching Huang
- Department of Microbiology, College of Medicine, National Taiwan University, Taipei, 10051, Taiwan
| | - Zih-Jie Shen
- Department of Microbiology, College of Medicine, National Taiwan University, Taipei, 10051, Taiwan
| | - Pang-Hung Hsu
- Department of Bioscience and Biotechnology, National Taiwan Ocean University, Keelung, 20224, Taiwan
| | - Meng-Hsun Hsieh
- Department of Microbiology, College of Medicine, National Taiwan University, Taipei, 10051, Taiwan
| | - Chia-Wei Yang
- Department of Microbiology, College of Medicine, National Taiwan University, Taipei, 10051, Taiwan
| | - Silvia Tognetti
- Cell Signaling Research Group, Departament de Ciències Experimentals i de la Salut, Universitat Pompeu Fabra, Barcelona, 08003, Spain
| | - Berta Canal
- Cell Signaling Research Group, Departament de Ciències Experimentals i de la Salut, Universitat Pompeu Fabra, Barcelona, 08003, Spain
| | - Laia Subirana
- Cell Signaling Research Group, Departament de Ciències Experimentals i de la Salut, Universitat Pompeu Fabra, Barcelona, 08003, Spain
| | - Chien-Wei Wang
- Department of Microbiology, College of Medicine, National Taiwan University, Taipei, 10051, Taiwan
| | - Hsiao-Tan Chen
- Department of Microbiology, College of Medicine, National Taiwan University, Taipei, 10051, Taiwan
| | - Chi-Ying Lin
- Department of Microbiology, College of Medicine, National Taiwan University, Taipei, 10051, Taiwan
| | - Francesc Posas
- Cell Signaling Research Group, Departament de Ciències Experimentals i de la Salut, Universitat Pompeu Fabra, Barcelona, 08003, Spain
| | - Shu-Chun Teng
- Department of Microbiology, College of Medicine, National Taiwan University, Taipei, 10051, Taiwan.
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7
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Abstract
Obesity is reaching global epidemic proportions as a result of factors such as high-calorie diets and lack of physical exercise. Obesity is now considered to be a medical condition, which not only contributes to the risk of developing type 2 diabetes mellitus, cardiovascular disease and cancer, but also negatively affects longevity and quality of life. To combat this epidemic, anti-obesogenic approaches are required that are safe, widely available and inexpensive. Several plants and mushrooms that are consumed in traditional Chinese medicine or as nutraceuticals contain antioxidants, fibre and other phytochemicals, and have anti-obesogenic and antidiabetic effects through the modulation of diverse cellular and physiological pathways. These effects include appetite reduction, modulation of lipid absorption and metabolism, enhancement of insulin sensitivity, thermogenesis and changes in the gut microbiota. In this Review, we describe the molecular mechanisms that underlie the anti-obesogenic and antidiabetic effects of these plants and mushrooms, and propose that combining these food items with existing anti-obesogenic approaches might help to reduce obesity and its complications.
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Affiliation(s)
- Jan Martel
- Center for Molecular and Clinical Immunology, Chang Gung University, 259 Wen-Hua First Road, Taoyuan 33302, Taiwan, Republic of China
- Chang Gung Immunology Consortium, Linkou Chang Gung Memorial Hospital, 5 Fu-Hsing Street, Taoyuan 33305, Taiwan, Republic of China
| | - David M Ojcius
- Center for Molecular and Clinical Immunology, Chang Gung University, 259 Wen-Hua First Road, Taoyuan 33302, Taiwan, Republic of China
- Chang Gung Immunology Consortium, Linkou Chang Gung Memorial Hospital, 5 Fu-Hsing Street, Taoyuan 33305, Taiwan, Republic of China
- Department of Biomedical Sciences, University of the Pacific, Arthur Dugoni School of Dentistry, 155 Fifth Street, San Francisco, California 94103, USA
| | - Chih-Jung Chang
- Center for Molecular and Clinical Immunology, Chang Gung University, 259 Wen-Hua First Road, Taoyuan 33302, Taiwan, Republic of China
- Chang Gung Immunology Consortium, Linkou Chang Gung Memorial Hospital, 5 Fu-Hsing Street, Taoyuan 33305, Taiwan, Republic of China
- Department of Medical Biotechnology and Laboratory Science, College of Medicine, Chang Gung University, 259 Wen-Hua First Road, Taoyuan 33302, Taiwan, Republic of China
- Department of Microbiology and Immunology, Chang Gung University, 259 Wen-Hua First Road, Taoyuan 33302, Taiwan, Republic of China
- Research Center of Bacterial Pathogenesis, Chang Gung University, 259 Wen-Hua First Road, Taoyuan 33302, Taiwan, Republic of China
| | - Chuan-Sheng Lin
- Center for Molecular and Clinical Immunology, Chang Gung University, 259 Wen-Hua First Road, Taoyuan 33302, Taiwan, Republic of China
- Chang Gung Immunology Consortium, Linkou Chang Gung Memorial Hospital, 5 Fu-Hsing Street, Taoyuan 33305, Taiwan, Republic of China
- Department of Medical Biotechnology and Laboratory Science, College of Medicine, Chang Gung University, 259 Wen-Hua First Road, Taoyuan 33302, Taiwan, Republic of China
- Department of Microbiology and Immunology, Chang Gung University, 259 Wen-Hua First Road, Taoyuan 33302, Taiwan, Republic of China
- Research Center of Bacterial Pathogenesis, Chang Gung University, 259 Wen-Hua First Road, Taoyuan 33302, Taiwan, Republic of China
| | - Chia-Chen Lu
- Department of Respiratory Therapy, Fu Jen Catholic University, 510 Zhong-Zheng Street, New Taipei City 24205, Taiwan, Republic of China
| | - Yun-Fei Ko
- Chang Gung Immunology Consortium, Linkou Chang Gung Memorial Hospital, 5 Fu-Hsing Street, Taoyuan 33305, Taiwan, Republic of China
- Chang Gung Biotechnology Corporation, 201 Tung-Hua North Road, Taipei 10508, Taiwan, Republic of China
- Biochemical Engineering Research Center, Ming Chi University of Technology, 84 Gungjuan Road, New Taipei City 24301, Taiwan, Republic of China
| | - Shun-Fu Tseng
- Chang Gung Immunology Consortium, Linkou Chang Gung Memorial Hospital, 5 Fu-Hsing Street, Taoyuan 33305, Taiwan, Republic of China
- Research Center of Bacterial Pathogenesis, Chang Gung University, 259 Wen-Hua First Road, Taoyuan 33302, Taiwan, Republic of China
| | - Hsin-Chih Lai
- Center for Molecular and Clinical Immunology, Chang Gung University, 259 Wen-Hua First Road, Taoyuan 33302, Taiwan, Republic of China
- Chang Gung Immunology Consortium, Linkou Chang Gung Memorial Hospital, 5 Fu-Hsing Street, Taoyuan 33305, Taiwan, Republic of China
- Department of Medical Biotechnology and Laboratory Science, College of Medicine, Chang Gung University, 259 Wen-Hua First Road, Taoyuan 33302, Taiwan, Republic of China
- Department of Microbiology and Immunology, Chang Gung University, 259 Wen-Hua First Road, Taoyuan 33302, Taiwan, Republic of China
- Research Center of Bacterial Pathogenesis, Chang Gung University, 259 Wen-Hua First Road, Taoyuan 33302, Taiwan, Republic of China
- Department of Laboratory Medicine, Linkou Chang Gung Memorial Hospital, 5 Fu-Hsing Street, Taoyuan 33305, Taiwan, Republic of China
- Research Center for Industry of Human Ecology, College of Human Ecology, Chang Gung University of Science and Technology, 261 Wen-Hua First Road, Taoyuan 33303, Taiwan, Republic of China
- Graduate Institute of Health Industry and Technology, College of Human Ecology, Chang Gung University of Science and Technology, 261 Wen-Hua First Road, Taoyuan 33303, Taiwan, Republic of China
| | - John D Young
- Center for Molecular and Clinical Immunology, Chang Gung University, 259 Wen-Hua First Road, Taoyuan 33302, Taiwan, Republic of China
- Chang Gung Immunology Consortium, Linkou Chang Gung Memorial Hospital, 5 Fu-Hsing Street, Taoyuan 33305, Taiwan, Republic of China
- Chang Gung Biotechnology Corporation, 201 Tung-Hua North Road, Taipei 10508, Taiwan, Republic of China
- Biochemical Engineering Research Center, Ming Chi University of Technology, 84 Gungjuan Road, New Taipei City 24301, Taiwan, Republic of China
- Laboratory of Cellular Physiology and Immunology, Rockefeller University, 1230 York Avenue, New York, New York 10021, USA
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8
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Ko YF, Liau JC, Lee CS, Chiu CY, Martel J, Lin CS, Tseng SF, Ojcius DM, Lu CC, Lai HC, Young JD. Isolation, Culture and Characterization of Hirsutella sinensis Mycelium from Caterpillar Fungus Fruiting Body. PLoS One 2017; 12:e0168734. [PMID: 28046129 PMCID: PMC5207747 DOI: 10.1371/journal.pone.0168734] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Accepted: 12/05/2016] [Indexed: 02/07/2023] Open
Abstract
The caterpillar fungus Ophiocordyceps sinensis (previously called Cordyceps sinensis) has been used for centuries in Asia as a tonic to improve health and longevity. Recent studies show that O. sinensis produces a wide range of biological effects on cells, laboratory animals and humans, including anti-fatigue, anti-infection, anti-inflammatory, antioxidant, and anti-tumor activities. In view of the rarity of O. sinensis fruiting bodies in nature, cultivation of its anamorph mycelium represents a useful alternative for large-scale production. However, O. sinensis fruiting bodies harvested in nature harbor several fungal contaminants, a phenomenon that led to the isolation and characterization of a large number of incorrect mycelium strains. We report here the isolation of a mycelium from a fruiting body of O. sinensis and we identify the isolate as O. sinensis’ anamorph (also called Hirsutella sinensis) based on multi-locus sequence typing of several fungal genes (ITS, nrSSU, nrLSU, RPB1, RPB2, MCM7, β-tubulin, TEF-1α, and ATP6). The main characteristics of the isolated mycelium, including its optimal growth at low temperature (16°C) and its biochemical composition, are similar to that of O. sinensis fruiting bodies, indicating that the mycelium strain characterized here may be used as a substitute for the rare and expensive O. sinensis fruiting bodies found in nature.
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Affiliation(s)
- Yun-Fei Ko
- Chang Gung Biotechnology Corporation, Taipei, Taiwan, Republic of China
- Biochemical Engineering Research Center, Ming Chi University of Technology, New Taipei City, Taiwan, Republic of China
- Chang Gung Immunology Consortium, Linkou Chang Gung Memorial Hospital, New Taipei City, Taiwan, Republic of China, and Chang Gung University, Gueishan, Taoyuan, Taiwan, Republic of China
| | - Jian-Ching Liau
- Chang Gung Biotechnology Corporation, Taipei, Taiwan, Republic of China
| | - Chien-Sheng Lee
- Chang Gung Biotechnology Corporation, Taipei, Taiwan, Republic of China
| | - Chen-Yaw Chiu
- Biochemical Engineering Research Center, Ming Chi University of Technology, New Taipei City, Taiwan, Republic of China
| | - Jan Martel
- Chang Gung Immunology Consortium, Linkou Chang Gung Memorial Hospital, New Taipei City, Taiwan, Republic of China, and Chang Gung University, Gueishan, Taoyuan, Taiwan, Republic of China
- Center for Molecular and Clinical Immunology, Chang Gung University, Taoyuan, Taiwan, Republic of China
- Laboratory of Nanomaterials, Chang Gung University, Gueishan, Taoyuan, Taiwan, Republic of China
| | - Chuan-Sheng Lin
- Chang Gung Immunology Consortium, Linkou Chang Gung Memorial Hospital, New Taipei City, Taiwan, Republic of China, and Chang Gung University, Gueishan, Taoyuan, Taiwan, Republic of China
- Center for Molecular and Clinical Immunology, Chang Gung University, Taoyuan, Taiwan, Republic of China
- Research Center of Bacterial Pathogenesis, Chang Gung University, Taoyuan, Taiwan, Republic of China
- Department of Medical Biotechnology and Laboratory Science, College of Medicine, Chang Gung University, Taoyuan, Taiwan, Republic of China
- Department of Microbiology and Immunology, College of Medicine, Chang Gung University, Taoyuan, Taiwan, Republic of China
| | - Shun-Fu Tseng
- Chang Gung Immunology Consortium, Linkou Chang Gung Memorial Hospital, New Taipei City, Taiwan, Republic of China, and Chang Gung University, Gueishan, Taoyuan, Taiwan, Republic of China
- Research Center of Bacterial Pathogenesis, Chang Gung University, Taoyuan, Taiwan, Republic of China
| | - David M. Ojcius
- Chang Gung Immunology Consortium, Linkou Chang Gung Memorial Hospital, New Taipei City, Taiwan, Republic of China, and Chang Gung University, Gueishan, Taoyuan, Taiwan, Republic of China
- Center for Molecular and Clinical Immunology, Chang Gung University, Taoyuan, Taiwan, Republic of China
- Department of Biomedical Sciences, University of the Pacific, Arthur Dugoni School of Dentistry, San Francisco, California, United States of America
| | - Chia-Chen Lu
- Chang Gung Immunology Consortium, Linkou Chang Gung Memorial Hospital, New Taipei City, Taiwan, Republic of China, and Chang Gung University, Gueishan, Taoyuan, Taiwan, Republic of China
- Department of Respiratory Therapy, Fu Jen Catholic University, New Taipei City, Taiwan, Republic of China
| | - Hsin-Chih Lai
- Chang Gung Immunology Consortium, Linkou Chang Gung Memorial Hospital, New Taipei City, Taiwan, Republic of China, and Chang Gung University, Gueishan, Taoyuan, Taiwan, Republic of China
- Center for Molecular and Clinical Immunology, Chang Gung University, Taoyuan, Taiwan, Republic of China
- Research Center of Bacterial Pathogenesis, Chang Gung University, Taoyuan, Taiwan, Republic of China
- Department of Medical Biotechnology and Laboratory Science, College of Medicine, Chang Gung University, Taoyuan, Taiwan, Republic of China
- Department of Microbiology and Immunology, College of Medicine, Chang Gung University, Taoyuan, Taiwan, Republic of China
- Department of Laboratory Medicine, Linkou Chang Gung Memorial Hospital, New Taipei City, Taiwan, Republic of China
- Research Center for Industry of Human Ecology, College of Human Ecology, Chang Gung University of Science and Technology, Taoyuan, Taiwan, Republic of China
- Graduate Institute of Health Industry and Technology, College of Human Ecology, Chang Gung University of Science and Technology, Taoyuan, Taiwan, Republic of China
| | - John D. Young
- Chang Gung Biotechnology Corporation, Taipei, Taiwan, Republic of China
- Biochemical Engineering Research Center, Ming Chi University of Technology, New Taipei City, Taiwan, Republic of China
- Chang Gung Immunology Consortium, Linkou Chang Gung Memorial Hospital, New Taipei City, Taiwan, Republic of China, and Chang Gung University, Gueishan, Taoyuan, Taiwan, Republic of China
- Center for Molecular and Clinical Immunology, Chang Gung University, Taoyuan, Taiwan, Republic of China
- Laboratory of Nanomaterials, Chang Gung University, Gueishan, Taoyuan, Taiwan, Republic of China
- Laboratory of Cellular Physiology and Immunology, The Rockefeller University, New York, New York, United States of America
- * E-mail:
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9
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Lin CS, Tsai YH, Chang CJ, Tseng SF, Wu TR, Lu CC, Wu TS, Lu JJ, Horng JT, Martel J, Ojcius DM, Lai HC, Young JD. An iron detection system determines bacterial swarming initiation and biofilm formation. Sci Rep 2016; 6:36747. [PMID: 27845335 PMCID: PMC5109203 DOI: 10.1038/srep36747] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [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: 06/15/2016] [Accepted: 10/20/2016] [Indexed: 11/30/2022] Open
Abstract
Iron availability affects swarming and biofilm formation in various bacterial species. However, how bacteria sense iron and coordinate swarming and biofilm formation remains unclear. Using Serratia marcescens as a model organism, we identify here a stage-specific iron-regulatory machinery comprising a two-component system (TCS) and the TCS-regulated iron chelator 2-isocyano-6,7-dihydroxycoumarin (ICDH-Coumarin) that directly senses and modulates environmental ferric iron (Fe3+) availability to determine swarming initiation and biofilm formation. We demonstrate that the two-component system RssA-RssB (RssAB) directly senses environmental ferric iron (Fe3+) and transcriptionally modulates biosynthesis of flagella and the iron chelator ICDH-Coumarin whose production requires the pvc cluster. Addition of Fe3+, or loss of ICDH-Coumarin due to pvc deletion results in prolonged RssAB signaling activation, leading to delayed swarming initiation and increased biofilm formation. We further show that ICDH-Coumarin is able to chelate Fe3+ to switch off RssAB signaling, triggering swarming initiation and biofilm reduction. Our findings reveal a novel cellular system that senses iron levels to regulate bacterial surface lifestyle.
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Affiliation(s)
- Chuan-Sheng Lin
- Department of Medical Biotechnology and Laboratory Science, Chang Gung University, Taoyuan, Taiwan, Republic of China.,Department of Biochemistry and Molecular Biology, Chang Gung University, Taoyuan, Taiwan, Republic of China.,Research Center of Bacterial Pathogenesis, Chang Gung University, Taoyuan, Taiwan, Republic of China.,Center for Molecular and Clinical Immunology, Chang Gung University, Taoyuan, Taiwan, Republic of China
| | - Yu-Huan Tsai
- Department of Medical Biotechnology and Laboratory Science, Chang Gung University, Taoyuan, Taiwan, Republic of China
| | - Chih-Jung Chang
- Department of Medical Biotechnology and Laboratory Science, Chang Gung University, Taoyuan, Taiwan, Republic of China.,Center for Molecular and Clinical Immunology, Chang Gung University, Taoyuan, Taiwan, Republic of China
| | - Shun-Fu Tseng
- Research Center of Bacterial Pathogenesis, Chang Gung University, Taoyuan, Taiwan, Republic of China
| | - Tsung-Ru Wu
- Department of Medical Biotechnology and Laboratory Science, Chang Gung University, Taoyuan, Taiwan, Republic of China
| | - Chia-Chen Lu
- Department of Respiratory Therapy, Fu Jen University, New Taipei City, Taiwan, Republic of China
| | - Ting-Shu Wu
- Department of Internal Medicine, Chang Gung Memorial Hospital, Taoyuan, Taiwan, Republic of China
| | - Jang-Jih Lu
- Department of Laboratory Medicine, Chang Gung Memorial Hospital, Taoyuan, Taiwan, Republic of China
| | - Jim-Tong Horng
- Department of Biochemistry and Molecular Biology, Chang Gung University, Taoyuan, Taiwan, Republic of China
| | - Jan Martel
- Center for Molecular and Clinical Immunology, Chang Gung University, Taoyuan, Taiwan, Republic of China
| | - David M Ojcius
- Center for Molecular and Clinical Immunology, Chang Gung University, Taoyuan, Taiwan, Republic of China.,Department of Biomedical Sciences, University of the Pacific, Arthur Dugoni School of Dentistry, San Francisco, United States of America
| | - Hsin-Chih Lai
- Department of Medical Biotechnology and Laboratory Science, Chang Gung University, Taoyuan, Taiwan, Republic of China.,Research Center of Bacterial Pathogenesis, Chang Gung University, Taoyuan, Taiwan, Republic of China.,Center for Molecular and Clinical Immunology, Chang Gung University, Taoyuan, Taiwan, Republic of China.,Department of Laboratory Medicine, Chang Gung Memorial Hospital, Taoyuan, Taiwan, Republic of China.,Research Center for Industry of Human Ecology, Chang Gung University of Science and Technology, Taoyuan, Taiwan, Republic of China.,Graduate Institute of Health Industry Technology, Chang Gung University of Science and Technology, Taoyuan, Taiwan, Republic of China
| | - John D Young
- Center for Molecular and Clinical Immunology, Chang Gung University, Taoyuan, Taiwan, Republic of China.,Laboratory of Cellular Physiology and Immunology, Rockefeller University, New York, United States of America.,Biochemical Engineering Research Center, Ming Chi University of Technology, New Taipei City, Taiwan, Republic of China
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10
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Kao L, Wang YT, Chen YC, Tseng SF, Jhang JC, Chen YJ, Teng SC. Global analysis of cdc14 dephosphorylation sites reveals essential regulatory role in mitosis and cytokinesis. Mol Cell Proteomics 2013; 13:594-605. [PMID: 24319056 DOI: 10.1074/mcp.m113.032680] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Degradation of the M phase cyclins triggers the exit from M phase. Cdc14 is the major phosphatase required for the exit from the M phase. One of the functions of Cdc14 is to dephosphorylate and activate the Cdh1/APC/C complex, resulting in the degradation of the M phase cyclins. However, other crucial targets of Cdc14 for mitosis and cytokinesis remain to be elucidated. Here we systematically analyzed the positions of dephosphorylation sites for Cdc14 in the budding yeast Saccharomyces cerevisiae. Quantitative mass spectrometry identified a total of 835 dephosphorylation sites on 455 potential Cdc14 substrates in vivo. We validated two events, and through functional studies we discovered that Cdc14-mediated dephosphorylation of Smc4 and Bud3 is essential for proper mitosis and cytokinesis, respectively. These results provide insight into the Cdc14-mediated pathways for exiting the M phase.
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Affiliation(s)
- Li Kao
- Department of Microbiology, College of Medicine, National Taiwan University, Taipei 10051, Taiwan
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11
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Wong CW, Hou PS, Tseng SF, Chien CL, Wu KJ, Chen HF, Ho HN, Kyo S, Teng SC. Krüppel-like transcription factor 4 contributes to maintenance of telomerase activity in stem cells. Stem Cells 2010; 28:1510-7. [PMID: 20629177 DOI: 10.1002/stem.477] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The zinc finger Krüppel-like transcription factor 4 (KLF4) has been implicated in cancer formation and stem cell regulation. However, the function of KLF4 in tumorigenesis and stem cell regulation are poorly understood due to limited knowledge of its targets in these cells. In this study, we have revealed a surprising link between KLF4 and regulation of telomerase that offers important insight into how KLF4 contributes to cancer formation and stem cell regulation. KLF4 sufficiently activated expression of the human telomerase catalytic subunit, human telomerase reverse transcriptase (hTERT), in telomerase-low alternative lengthening of telomeres (ALT), and fibroblast cells, while downregulation of KLF4 reduced its expression in cancerous and stem cells, which normally exhibits high expression. Furthermore, KLF4-dependent induction of hTERT was mediated by a KLF4 binding site in the proximal promoter region of hTERT. In human embryonic stem cells, expression of hTERT replaced KLF4 function to maintain their self-renewal. Therefore, our findings demonstrate that hTERT is one of the major targets of KLF4 in cancer and stem cells to maintain long-term proliferation potential.
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Affiliation(s)
- Chui-Wei Wong
- Department of Microbiology, College of Medicine, National Taiwan University, Taipei, Taiwan
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12
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Tseng SF, Shen ZJ, Tsai HJ, Lin YH, Teng SC. Rapid Cdc13 turnover and telomere length homeostasis are controlled by Cdk1-mediated phosphorylation of Cdc13. Nucleic Acids Res 2009; 37:3602-11. [PMID: 19359360 PMCID: PMC2699520 DOI: 10.1093/nar/gkp235] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Budding yeast telomerase is mainly activated by Tel1/Mec1 (yeast ATM/ATR) on Cdc13 from late S to G2 phase of the cell cycle. Here, we demonstrated that the telomerase-recruitment domain of Cdc13 is also phosphorylated by Cdk1 at the same cell cycle stage as the Tel1/Mec1-dependent regulation. Phosphor-specific gel analysis demonstrated that Cdk1 phosphorylates residues 308 and 336 of Cdc13. The residue T308 of Cdc13 is critical for efficient Mec1-mediated S306 phosphorylation in vitro. Phenotypic analysis in vivo revealed that the mutations in the Cdc13 S/TP motifs phosphorylated by Cdk1 caused cell cycle delay and telomere shortening and these phenotypes could be partially restored by the replacement with a negative charge residue. In the absence of Ku or Tel1, Cdk1-mediated phosphorylation of Cdc13 showed no effect on telomere length maintenance. Moreover, this Cdk1-mediated phosphorylation was required to promote the regular turnover of Cdc13. Together these results demonstrate that Cdk1 phosphorylates the telomerase recruitment domain of Cdc13, thereby preserves optimal function and expression level of Cdc13 for precise telomere replication and cell cycle progression.
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Affiliation(s)
- Shun-Fu Tseng
- Department of Microbiology, College of Medicine, National Taiwan University, Taipei, Taiwan
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13
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Tseng SF, Gabriel A, Teng SC. Proofreading activity of DNA polymerase Pol2 mediates 3'-end processing during nonhomologous end joining in yeast. PLoS Genet 2008; 4:e1000060. [PMID: 18437220 PMCID: PMC2312331 DOI: 10.1371/journal.pgen.1000060] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2007] [Accepted: 03/26/2008] [Indexed: 02/02/2023] Open
Abstract
Genotoxic agents that cause double-strand breaks (DSBs) often generate damage at the break termini. Processing enzymes, including nucleases and polymerases, must remove damaged bases and/or add new bases before completion of repair. Artemis is a nuclease involved in mammalian nonhomologous end joining (NHEJ), but in Saccharomyces cerevisiae the nucleases and polymerases involved in NHEJ pathways are poorly understood. Only Pol4 has been shown to fill the gap that may form by imprecise pairing of overhanging 3' DNA ends. We previously developed a chromosomal DSB assay in yeast to study factors involved in NHEJ. Here, we use this system to examine DNA polymerases required for NHEJ in yeast. We demonstrate that Pol2 is another major DNA polymerase involved in imprecise end joining. Pol1 modulates both imprecise end joining and more complex chromosomal rearrangements, and Pol3 is primarily involved in NHEJ-mediated chromosomal rearrangements. While Pol4 is the major polymerase to fill the gap that may form by imprecise pairing of overhanging 3' DNA ends, Pol2 is important for the recession of 3' flaps that can form during imprecise pairing. Indeed, a mutation in the 3'-5' exonuclease domain of Pol2 dramatically reduces the frequency of end joins formed with initial 3' flaps. Thus, Pol2 performs a key 3' end-processing step in NHEJ.
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Affiliation(s)
- Shun-Fu Tseng
- Department of Microbiology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Abram Gabriel
- Department of Biochemistry and Molecular Biology, Rutgers University, Piscataway, New Jersey, United States of America
| | - Shu-Chun Teng
- Department of Microbiology, College of Medicine, National Taiwan University, Taipei, Taiwan
- Institute of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan
- * E-mail:
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14
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Tseng SF, Lin JJ, Teng SC. The telomerase-recruitment domain of the telomere binding protein Cdc13 is regulated by Mec1p/Tel1p-dependent phosphorylation. Nucleic Acids Res 2006; 34:6327-36. [PMID: 17108359 PMCID: PMC1669766 DOI: 10.1093/nar/gkl786] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
The DNA damage-responsive protein kinases ATM and ATR phosphorylate SQ/TQ motifs that lie in clusters in most of their in vivo targets. Budding yeast Cdc13p contains two clusters of SQ/TQ motifs, suggesting that it might be a target of Mec1p/Tel1p (yeast ATR/ATM). Here we demonstrated that the telomerase recruitment domain of Cdc13p is phosphorylated by Mec1p and Tel1p. Gel analysis showed that Cdc13p contains a Mec1/Tel1-dependent post-translational modification. Using an immunoprecipitate (IP)-kinase assay, we showed that Mec1p phosphorylates Cdc13p on serine 225, 249, 255 and 306, and Tel1p phosphorylates Cdc13p on serine 225, 249 and 255 in vitro. Phenotypic analysis in vivo revealed that the mutations in the Cdc13p SQ motifs phosphorylated by Mec1p and Tel1p caused multiple telomere and growth defects. In addition, normal telomere length and growth could be restored by expressing a Cdc13-Est1p hybrid protein. These results demonstrate the telomerase recruitment domain of Cdc13p as an important new telomere-specific target of Mec1p/Tel1p.
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Affiliation(s)
- Shun-Fu Tseng
- Department of Microbiology, College of Medicine, National Taiwan UniversityTaipei, Taiwan
| | - Jing-Jer Lin
- Institute of Biopharmaceutical Science, National Yang-Ming UniversityTaipei, Taiwan
| | - Shu-Chun Teng
- Department of Microbiology, College of Medicine, National Taiwan UniversityTaipei, Taiwan
- Institute of Internal Medicine, National Taiwan University HospitalTaipei, Taiwan
- To whom correspondence should be addressed. Tel: +886 2 2312 3456, ext. 8282; Fax: +886 2 23915293;
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15
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Abstract
During the past 20 years, the MRE11-RAD50-NBS1 complex has become an increasingly important focus in basic and clinical cancer research. One main conceptual step forward was made with the discovery of NBS1 and the understanding of its critical pathophysiological role in Nijmegen breakage syndrome. Major efforts were carried out to define the role in DNA repair of this complex. Recently, basic research has continuously extended our understanding of the complexity of the NBS1 complex. MRE11-RAD50-NBS1 complex can no longer be viewed as having a single role in DNA damage repair since it also serves as a sensor and a mediator in cell cycle checkpoint signaling. Meanwhile, studies have challenged the concept that NBS1 only functions as a tumor suppressor in preserving genome integrity in the nucleus. It may also provide an oncogenic role in the cytoplasm which is associated with the PI3-kinase/AKT-activation pathway. Consistent with this aspect, a growing body of clinical evidence suggests that NBS1 contains a deleterious character that depends on its subcellular localization. This review focuses on recent experimental evidences demonstrating how NBS1 is translocated into the nucleus by an importin KPNA2 which mediates NBS1 subcellular localization and the functions of the NBS1 complex in tumorigenesis.
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Affiliation(s)
- Shu-Chun Teng
- Department of Microbiology, College of Medicine, National Taiwan University, No. 1 Sec. 1 Jen-Ai Road, Taipei 10063, Taiwan.
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16
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Tseng SF, Huang TW, Chen CW, Chern MK, Tam MF, Teng SC. ShyA, a membrane protein for proper septation of hyphae in Streptomyces. Biochem Biophys Res Commun 2006; 343:369-77. [PMID: 16545778 DOI: 10.1016/j.bbrc.2006.02.178] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2006] [Accepted: 02/28/2006] [Indexed: 11/20/2022]
Abstract
The life cycle of Streptomyces involves the formation of filamentous substrate and aerial hyphae. Following cessation of growth of an aerial hypha, multiple septation occurs at the tip to produce a chain of unigenomic spores. A gene, shyA, which influences several aspects of this growth, was isolated and partially characterized in Streptomyces coelicolor. The gene product is a representative of a well-conserved family of small actinomycete proteins. The shyA mutant sporulates normally but displays hyper septum formation and altered spore-chain morphology. Biochemical separation experiments and immunofluorescence staining demonstrated that the shyA gene product locates at cell membranes. Moreover, yeast two-hybrid screen and GST-pull-down assay showed that ShyA can interact with itself. Altogether, ShyA belongs to a new family of membrane-associated proteins which plays a role in morphological differentiation in actinomycetes.
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Affiliation(s)
- Shun-Fu Tseng
- Department of Microbiology, College of Medicine, National Taiwan University, Taipei 10063, Taiwan
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17
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Abstract
Telomere maintenance is required for chromosome stability, and telomeres are typically replicated by the action of telomerase. In both mammalian tumor and yeast cells that lack telomerase, telomeres are maintained by an alternative (ALT) recombination mechanism. In yeast, Sgs1p and its associated type IA topoisomerase, Top3p, may work coordinately in removing Holliday junction intermediates from a crossover-producing recombination pathway. Previous studies have also indicated that Sgs1 helicase acts in a telomere recombination pathway. Here we show that topoisomerase III is involved in telomere-telomere recombination. The recovery of telomere recombination-dependent survivors in a telomerase-minus yeast strain was dependent on Top3p catalytic activity. Moreover, the RIF1 and RIF2 genes are required for the establishment of TOP3/SGS1-dependent telomere-telomere recombination. In human Saos-2 ALT cells, human topoisomerase IIIalpha (hTOP3alpha) also contributes to telomere recombination. Strikingly, the telomerase activity is clearly enhanced in surviving si-hTOP3alpha Saos-2 ALT cells. Altogether, the present results suggest a potential role for hTOP3alpha in dissociating telomeric structures in telomerase-deficient cells, providing therapeutic implications in human tumors.
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Affiliation(s)
- Hung-Ji Tsai
- Department of Microbiology, College of Medicine, National Taiwan University, No. 1, Sec. 1, Jen-Ai Road, Taipei 10018, Taiwan
| | - Wei-Hsiang Huang
- Department of Microbiology, College of Medicine, National Taiwan University, No. 1, Sec. 1, Jen-Ai Road, Taipei 10018, Taiwan
| | - Tsai-Kun Li
- Department of Microbiology, College of Medicine, National Taiwan University, No. 1, Sec. 1, Jen-Ai Road, Taipei 10018, Taiwan
| | - Yun-Luen Tsai
- Department of Microbiology, College of Medicine, National Taiwan University, No. 1, Sec. 1, Jen-Ai Road, Taipei 10018, Taiwan
| | - Kou-Juey Wu
- Institute of Biochemistry, National Yang-Ming University, Taipei 11221, Taiwan
| | - Shun-Fu Tseng
- Department of Microbiology, College of Medicine, National Taiwan University, No. 1, Sec. 1, Jen-Ai Road, Taipei 10018, Taiwan
| | - Shu-Chun Teng
- Department of Microbiology, College of Medicine, National Taiwan University, No. 1, Sec. 1, Jen-Ai Road, Taipei 10018, Taiwan; Institute of Internal Medicine, National Taiwan University Hospital, Taipei 10018, Taiwan.
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18
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Wen WY, Tsai HJ, Lin CC, Tseng SF, Wong CW, Teng SC. Telomere configuration influences the choice of telomere maintenance pathways. Biochem Biophys Res Commun 2006; 343:459-66. [PMID: 16546132 DOI: 10.1016/j.bbrc.2006.03.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2006] [Accepted: 03/03/2006] [Indexed: 10/24/2022]
Abstract
Telomere maintenance is required for chromosome stability, and telomeres are typically replicated by the action of telomerase. In yeast cells that lack telomerase, telomeres are maintained by alternative type I and type II recombination mechanisms. Previous studies identified several proteins to control the choice between two types of recombinations. Here, we demonstrate that configuration of telomeres also plays a role to determine the fate of telomere replication in progeny. When diploid yeasts from mating equip with a specific type of telomeric structure in their genomes, they prefer to maintain this type of telomere replication in their descendants. While inherited telomere structure is easier to be utilized in progeny at the beginning stage, the telomeres in type I diploids can gradually switch to the type II cells in liquid culture. Importantly, the TLC1/tlc1 yeast cells develop type II survivors suggesting that haploid insufficiency of telomerase RNA component, which is similar to a type of dyskeratosis congenital in human. Altogether, our results suggest that both protein factors and substrate availability contribute to the choice among telomere replication pathways in yeast.
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Affiliation(s)
- Wan-Ying Wen
- Department of Microbiology, College of Medicine, National Taiwan University, Taipei 100, Taiwan, ROC
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19
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Abstract
Nijmegen breakage syndrome (NBS) is a chromosomal-instability syndrome associated with cancer predisposition, radiosensitivity, microcephaly, and growth retardation. The NBS gene product, NBS1, is a component of the MRE11-RAD50-NBS1 (MRN) complex, a central player associated with double strand break (DSB) repair. In response to radiation, NBS1 is phosphorylated by ATM, and the MRN complex relocalizes to form punctate nuclear foci for DNA repair. NBS1 controls both the nuclear localization of the MRN complexes and radiation-induced focus formation. We report here that the KPNA2 (importin alpha1) is important for the normal nuclear localization of the MRN complex and its proper formation of the nuclear foci. KPNA2 is the only member of the importin alpha family that physically interacts with NBS1, and the KPNA2-mediated nucleus localization sequence (NLS) is mapped to amino acid residues 461-467 of NBS1 that is sufficient for both the interaction with KPNA2 and the proper nuclear localization. Inhibition of KPNA2 or blockage of the KPNA2 interaction with NBS1 results in a reduction of radiation-induced nuclear focus accumulation, DSB repair, and cell cycle checkpoint signaling of NBS1. Collectively, our results strongly suggest that an interaction with KPNA2 contributes to nuclear localization and multiple tumor suppression functions of the NBS1 complex.
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Affiliation(s)
- Shun-Fu Tseng
- Department of Microbiology, College of Medicine, National Taiwan University, No. 1, Section 1, Jen-Ai Road, Taipei 10018, Taiwan
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20
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Lin CY, Chang HH, Wu KJ, Tseng SF, Lin CC, Lin CP, Teng SC. Extrachromosomal telomeric circles contribute to Rad52-, Rad50-, and polymerase delta-mediated telomere-telomere recombination in Saccharomyces cerevisiae. Eukaryot Cell 2005; 4:327-36. [PMID: 15701795 PMCID: PMC549320 DOI: 10.1128/ec.4.2.327-336.2005] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Telomere maintenance is required for chromosome stability, and telomeres are typically replicated by the telomerase reverse transcriptase. In both tumor and yeast cells that lack telomerase, telomeres are maintained by an alternative recombination mechanism. By using an in vivo inducible Cre-loxP system to generate and trace the fate of marked telomeric DNA-containing rings, the efficiency of telomere-telomere recombination can be determined quantitatively. We show that the telomeric loci are the primary sites at which a marked telomeric ring-containing DNA is observed among wild-type and surviving cells lacking telomerase. Marked telomeric DNAs can be transferred to telomeres and form tandem arrays through Rad52-, Rad50-, and polymerase delta-mediated recombination. Moreover, increases of extrachromosomal telomeric and Y' rings were observed in telomerase-deficient cells. These results imply that telomeres can use looped-out telomeric rings to promote telomere-telomere recombination in telomerase-deficient Saccharomyces cerevisiae.
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Affiliation(s)
- Chi-Ying Lin
- Department of Microbiology, National Taiwan University College of Medicine,Taipei 10018, Taiwan
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21
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Lin CC, Tsai YL, Huang MT, Lu YP, Ho CT, Tseng SF, Teng SC. Inhibition of estradiol-induced mammary proliferation by dibenzoylmethane through the E 2 –ER–ERE-dependent pathway. Carcinogenesis 2005; 27:131-6. [PMID: 16051634 DOI: 10.1093/carcin/bgi199] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [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: 11/12/2022] Open
Abstract
The phytochemical dibenzoylmethane (DBM) has been shown to inhibit 7,12-dimethylbenz[a]anthracene induced mammary tumorigenesis in Sencar mice. However, the molecular basis of this activity is still elusive. In the present study, we demonstrated that DBM inhibits estradiol (E2)-induced incorporation of bromodeoxyuridine into mammary DNA in immature female Sencar mice by 52%, when 10 micromol of DBM was intraperitoneally injected into mice prior to the injection of E2. Examination of the influence of DBM on the expressions of E2-ERE-dependent oncogenes in MCF-7 cells indicated that DBM inhibits the E2-induced cell growth as well as the expressions of four oncogenes, telomerase, c-myc, Ha-ras and bcl-2. Further mechanistic study using chromatin immunoprecipitation assay demonstrated that DBM acts as a pure antagonist by attenuating the binding of estrogen receptor to the estrogen response elements in the regulatory regions of c-myc, hTERT and bcl-2 genes in vivo. Taken together, our results strongly suggest that DBM plays an inhibitory role in E2-induced proliferations, which establishes DBM as a model molecule for studying the antiestrogenic drugs.
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MESH Headings
- Animals
- Breast Neoplasms/drug therapy
- Breast Neoplasms/metabolism
- Breast Neoplasms/pathology
- Bromodeoxyuridine
- Cell Proliferation/drug effects
- Chalcones/pharmacology
- Chromatin Immunoprecipitation
- Diet
- Estradiol/pharmacology
- Estrogen Antagonists/pharmacology
- Female
- Genes, ras/genetics
- Humans
- Injections, Intraperitoneal
- Mammary Glands, Animal/cytology
- Mammary Glands, Animal/drug effects
- Mammary Glands, Animal/metabolism
- Mice
- Mice, Inbred SENCAR
- Proto-Oncogene Proteins c-bcl-2/genetics
- Proto-Oncogene Proteins c-bcl-2/metabolism
- Proto-Oncogene Proteins c-myc/genetics
- Proto-Oncogene Proteins c-myc/metabolism
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Receptors, Estrogen/metabolism
- Response Elements
- Reverse Transcriptase Polymerase Chain Reaction
- Signal Transduction/drug effects
- Telomerase/genetics
- Telomerase/metabolism
- Tumor Cells, Cultured
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Affiliation(s)
- Chuan-Chuan Lin
- Department of Food Science, China Institute of Technology, and National Taiwan University Hospital, Taipei, Taiwan
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22
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Teng SC, Chen YY, Su YN, Chou PC, Chiang YC, Tseng SF, Wu KJ. Direct Activation of HSP90A Transcription by c-Myc Contributes to c-Myc-induced Transformation. J Biol Chem 2004; 279:14649-55. [PMID: 14724288 DOI: 10.1074/jbc.m308842200] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The c-myc proto-oncogene encodes a ubiquitous transcription factor involved in the control of cell growth and differentiation and implicated in inducing tumorigenesis. Understanding the function of c-Myc and its role in cancer depends upon the identification of c-Myc target genes. Heat shock protein 90 (HSP90) is involved in the folding of proteins such as signal transduction molecules (Src, Raf1, cdk4) and steroid receptors and in enhancing the activity of telomerase and nitric-oxide synthase. Here we show that c-Myc directly activates HSP90A transcription. c-Myc-mediated induction of HSP90A transcription occurs in different tissues, is independent of cell proliferation, and is mediated by a c-Myc binding site in the proximal promoter region of HSP90A gene. Overexpression of HSP90A in Rat1a cells induces transformation. Short interference RNA of HSP90A/Hsp86alpha reduces transformation activity in HeLa and RatMyc cells. These results indicate that by induction of HSP90A c-Myc may control the activity of multiple signal pathways involved in cellular transformation.
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MESH Headings
- Agar/metabolism
- Animals
- Binding Sites
- Blotting, Northern
- Blotting, Western
- Cell Division
- Cell Line
- Cell Line, Tumor
- Cell Transformation, Neoplastic
- Chromatin/metabolism
- Cloning, Molecular
- Genes, Reporter
- HSP90 Heat-Shock Proteins/metabolism
- HeLa Cells
- Humans
- Luciferases/metabolism
- Mice
- Mice, Nude
- NIH 3T3 Cells
- Plasmids/metabolism
- Precipitin Tests
- Promoter Regions, Genetic
- Proto-Oncogene Mas
- Proto-Oncogene Proteins c-myc/metabolism
- RNA, Small Interfering/metabolism
- Rats
- Signal Transduction
- Transcription, Genetic
- Transfection
- U937 Cells
- Up-Regulation
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Affiliation(s)
- Shu-Chun Teng
- Institute of Biochemistry, National Yang-Ming University, Taipei 112, Taiwan
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23
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Tsai YL, Tseng SF, Chang SH, Lin CC, Teng SC. Involvement of replicative polymerases, Tel1p, Mec1p, Cdc13p, and the Ku complex in telomere-telomere recombination. Mol Cell Biol 2002; 22:5679-87. [PMID: 12138180 PMCID: PMC133992 DOI: 10.1128/mcb.22.16.5679-5687.2002] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.2] [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: 11/20/2022] Open
Abstract
Telomere maintenance is required for chromosome stability, and telomeres are typically replicated by the action of the reverse transcriptase telomerase. In both tumor and yeast cells that lack telomerase, telomeres are maintained by an alternative recombination mechanism. Genetic studies have led to the identification of DNA polymerases, cell cycle checkpoint proteins, and telomere binding proteins involved in the telomerase pathway. However, how these proteins affect telomere-telomere recombination has not been identified to date. Using an assay to trace the in vivo recombinational products throughout the course of survivor development, we show here that three major replicative polymerases, alpha, delta, and epsilon, play roles in telomere-telomere recombination and that each causes different effects and phenotypes when they as well as the telomerase are defective. Polymerase delta appears to be the main activity for telomere extension, since neither type I nor type II survivors arising via telomere-telomere recombination were seen in its absence. The frequency of type I versus type II is altered in the polymerase alpha and epsilon mutants relative to the wild type. Each prefers to develop a particular type of survivor. Moreover, type II recombination is mediated by the cell cycle checkpoint proteins Tel1 and Mec1, and telomere-telomere recombination is regulated by telomere binding protein Cdc13 and the Ku complex. Together, our results suggest that coordination between DNA replication machinery, DNA damage signaling, DNA recombination machinery, and the telomere protein-DNA complex allows telomere recombination to repair telomeric ends in the absence of telomerase.
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Affiliation(s)
- Yun-Luen Tsai
- Department of Microbiology, National Taiwan University College of Medicine, Taipei, Taiwan, Republic of China
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24
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Tseng IJ, Chen YT, Chen MT, Kou HY, Tseng SF. Prevalence of urinary incontinence and intention to seek treatment in the elderly. J Formos Med Assoc 2000; 99:753-8. [PMID: 11061069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023] Open
Abstract
BACKGROUND AND PURPOSE Urinary incontinence (UI) is a common, distressing, and often disabling condition in the elderly. The objectives of this study were to estimate the prevalence and clinical characteristics of UI among elderly individuals living at home and to explore their perceptions of UI and intention to seek medical care. METHODS A total of 504 elderly subjects aged 65 and older residing in Tungkang town (located in the southwestern part of Taiwan) were randomly sampled and surveyed face to face by registered nurses. The prevalence, clinical types, and perceptions of UI, and intention to seek treatment, were compared with chi-square statistics across various sociodemographic characteristics. Logistic regression analyses were conducted to identify factors associated with UI experience and intention to seek treatment. RESULTS About 22% of respondents reported that they had experienced involuntary loss of urine in daily life. Women, people who were overweight, and those who were aged 70 years or older were at higher risk of UI. While women were more likely to suffer from stress incontinence, men were at higher risk of urge incontinence. Women, illiterate individuals, and those who perceived UI as a normal part of the aging process showed low intention to seek treatment for UI. CONCLUSIONS The results of this study suggest that public awareness programs about UI and promotion of available treatment options are necessary to increase the intention to seek treatment among the elderly. Culturally sensitive programs should be designed, particularly for female and illiterate elderly, to provide incentives to seek medical care. The increasing availability of various treatment modalities coupled with education to correct commonly held misconceptions about UI might enable more elderly individuals to receive treatment for this common condition.
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Affiliation(s)
- I J Tseng
- Department of Urology, Affiliated Hospital of Foo-Yin Institute of Technology, Tungkang, Pingtung, Taiwan
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25
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Chen CJ, Tseng SF, Lu CF, Lin HC, You SL, Chen CS, Hwang SJ, Hsieh SF, Hsu ST. Current seroepidemiology of hepatitis D virus infection among hepatitis B surface antigen carriers of general and high-risk populations in Taiwan. J Med Virol 1992; 38:97-101. [PMID: 1460460 DOI: 10.1002/jmv.1890380205] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [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: 12/27/2022]
Abstract
In order to assess the current seroepidemiology of hepatitis D virus (HDV) infection in Taiwan where hepatitis B virus (HBV) is hyperendemic, a total of 756 voluntary blood donors, 641 prostitutes, 1,014 patients with sexually transmitted diseases (STDs), and 628 drug abusers were studied. Radioimmunoassays were used for testing HBV infection markers and antibody against HDV (anti-HDV) among HBsAg carriers. The anti-HDV prevalence among HBsAg carriers was significantly higher in STD patients (9.6%), prostitutes (33.1%), and drug abusers (68.1%) than in blood donors from the general population (2.2%). The prevalence gradually increased with age in blood donors and STD patients, but reached a plateau at a young age in prostitutes and drug abusers. Males had a higher prevalence than females in blood donors (2.7% vs. 0), STD patients (8.2% vs. 7.5%), and drug abusers (69.0% vs. 57.1%), but the difference was not statistically significant. STD patients with syphilis had a higher prevalence (19.5%) than those affected with non-ulcerating STDs (5.3%). While unlicensed prostitutes had a lower prevalence (13.6%) than licensed prostitutes (44.9%), intravenous drug abusers had a higher prevalence (73.1%) than non-intravenous drug abusers (34.6%). There was a twofold increase in anti-HDV prevalence from 1986 to 1989 among prostitutes, but the prevalence remained unchanged in the general population and drug abusers. HDV infection remains limited to the high-risk groups and spread mainly by promiscuity and needle sharing in Taiwan.
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Affiliation(s)
- C J Chen
- Institute of Public Health, National Taiwan University College of Medicine, Republic of China
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26
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Lin JK, Tseng SF. Chromosomal aberrations and sister-chromatid exchanges induced by N-nitroso-2-acetylaminofluorene and their modifications by arsenite and selenite in Chinese hamster ovary cells. Mutat Res 1992; 265:203-10. [PMID: 1370719 DOI: 10.1016/0027-5107(92)90049-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [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: 10/27/2022]
Abstract
The frequencies of chromosomal aberrations (CA) and sister-chromatid exchanges (SCE) in Chinese hamster cells were significantly increased by the direct-acting mutagen N-nitroso-2-acetylaminofluorene (N-NO-AAF) at the concentration of 0.1 mM. N-NO-AAF was prepared by nitrosation of the protohepatocarcinogen 2-acetylaminofluorene. The induced CA, which included chromatid breaks, chromatid exchanges, chromosome breaks, and chromosome ring formation were significantly potentiated by the presence of sodium arsenite (10 microM), but not by hydroxyurea (20 mM) or cytosine arabinoside (25 microM). On the other hand, the clastogenic effect of N-NO-AAF was effectively inhibited by sodium selenite (100 microM). Arsenite (10 microM) was shown to be moderately active in CA induction which was partially blocked by the presence of selenite (10 nM). N-Nitroso compounds such as N-nitroso-N-methylurea, N-nitroso-N-ethylurea and N-methyl-N'-nitro-N-nitrosoguanidine were equally or more active in the induction of CA and SCE in CHO cells when compared with N-NO-AAF. The cell cycle was significantly delayed by the intervention of N-NO-AAF.
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Affiliation(s)
- J K Lin
- Institute of Biochemistry, College of Medicine, National Taiwan University, Taipei, Republic of China
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