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Unnisa A, Greig NH, Kamal MA. Inhibition of Caspase 3 and Caspase 9 Mediated Apoptosis: A Multimodal Therapeutic Target in Traumatic Brain Injury. Curr Neuropharmacol 2023; 21:1001-1012. [PMID: 35339178 PMCID: PMC10227914 DOI: 10.2174/1570159x20666220327222921] [Citation(s) in RCA: 27] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 02/17/2022] [Accepted: 03/23/2022] [Indexed: 02/08/2023] Open
Abstract
Traumatic brain injury (TBI) is one of the significant causes of death and morbidity, and it is hence a focus of translational research. Apoptosis plays an essential part in the pathophysiology of TBI, and its inhibition may help overcome TBI's negative consequences and improve functional recovery. Although physiological neuronal death is necessary for appropriate embryologic development and adult cell turnover, it can also drive neurodegeneration. Caspases are principal mediators of cell death due to apoptosis and are critical for the required cleavage of intracellular proteins of cells committed to die. Caspase-3 is the major executioner Caspase of apoptosis and is regulated by a range of cellular components during physiological and pathological conditions. Activation of Caspase-3 causes proteolyzation of DNA repair proteins, cytoskeletal proteins, and the inhibitor of Caspase-activated DNase (ICAD) during programmed cell death, resulting in morphological alterations and DNA damage that define apoptosis. Caspase-9 is an additional crucial part of the intrinsic pathway, activated in response to several stimuli. Caspases can be altered post-translationally or by modulatory elements interacting with the zymogenic or active form of a Caspase, preventing their activation. The necessity of Caspase-9 and -3 in diverse apoptotic situations suggests that mammalian cells have at least four distinct apoptotic pathways. Continued investigation of these processes is anticipated to disclose new Caspase regulatory mechanisms with consequences far beyond apoptotic cell death control. The present review discusses various Caspase-dependent apoptotic pathways and the treatment strategies to inhibit the Caspases potentially.
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Affiliation(s)
- Aziz Unnisa
- Department of Pharmacology, College of Pharmacy, University of Hail, Hail, KSA;
| | - Nigel H. Greig
- Drug Design & Development Section, Translational Gerontology Branch, Intramural Research Program, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - Mohammad Amjad Kamal
- Institutes for Systems Genetics, Frontiers Science Center for Disease-related Molecular Network, West China Hospital, Sichuan University, Chengdu, China
- King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia
- Department of Pharmacy, Faculty of Allied Health Sciences, Daffodil International University, Dhaka, Bangladesh
- Enzymoics, 7 Peterlee Place, Hebersham, NSW 2770; Novel Global Community Educational Foundation, NSW, Australia
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2
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Shi Q, Ni X, Lei M, Xia Q, Dong Y, Zhang Q, Wang W. Phosphorylation of islet-1 serine 269 by CDK1 increases its transcriptional activity and promotes cell proliferation in gastric cancer. Mol Med 2021; 27:47. [PMID: 33962568 PMCID: PMC8106192 DOI: 10.1186/s10020-021-00302-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Accepted: 04/14/2021] [Indexed: 12/31/2022] Open
Abstract
Background Despite recent advances in diagnostic and therapeutic approaches for gastric cancer (GC), the survival of patients with advanced GC remains very low. Islet-1 (ISL1) is a LIM-homeodomain transcription factor, which is upregulated and promotes cell proliferation in GC. The exact mechanism by which ISL1 influences GC development is unclear. Methods Co-immunoprecipitation (co-IP) and glutathione S-transferase (GST)-pulldown assays were employed to evaluate the interaction of ISL1 with CDK1. Western blot and immunohistochemistry analyses were performed to evaluate the ability of CDK1 to phosphorylate ISL1 at Ser 269 in GC cell and tissue specimens. Chromatin immunoprecipitation (ChIP), ChIP re-IP, luciferase reporter, and CCK-8 assays were combined with flow cytometry cell cycle analysis to detect the transactivation potency of ISL1-S269-p and its ability to promote cell proliferation. The self-stability and interaction with CDK1 of ISL1-S269-p were also determined. Results ISL1 is phosphorylated by CDK1 at serine 269 (S269) in vivo. Phosphorylation of ISL1 by CDK1 on serine 269 strengthened its binding on the cyclin B1 and cyclin B2 promoters and increased its transcriptional activity in GC. Furthermore, CDK1-dependent phosphorylation of ISL1 correlated positively with ISL1 protein self-stability in NIH3T3 cells. Conclusions ISL1-S269-p increased ISL1 transcriptional activity and self-stability while binding to the cyclinB1 and cyclinB2 promoters promotes cell proliferation. ISL1-S269-p is therefore crucial for tumorigenesis and potentially a direct therapeutic target for GC. Supplementary Information The online version contains supplementary material available at 10.1186/s10020-021-00302-6.
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Affiliation(s)
- Qiong Shi
- Clinical Laboratory, The Third Affiliated Hospital, Kunming Medical University & Yunnan Cancer Center, Yunnan, Kunming, P. R. China
| | - Xiaomei Ni
- Clinical Laboratory, The Third Affiliated Hospital, Kunming Medical University & Yunnan Cancer Center, Yunnan, Kunming, P. R. China
| | - Ming Lei
- Clinical Laboratory, The Third Affiliated Hospital, Kunming Medical University & Yunnan Cancer Center, Yunnan, Kunming, P. R. China
| | - Quansong Xia
- Clinical Laboratory, The Third Affiliated Hospital, Kunming Medical University & Yunnan Cancer Center, Yunnan, Kunming, P. R. China
| | - Yan Dong
- Pathology Department, The Third Affiliated Hospital, Kunming Medical University & Yunnan Cancer Center, Yunnan, Kunming, P. R. China
| | - Qiao Zhang
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Kunming Medical University, Yunnan, Kunming, P. R. China
| | - Weiping Wang
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Beijing Key Laboratory of Protein Posttranslational Modifications and Cell Function, Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education of China, Peking University, Beijing, P. R. China.
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3
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Perfetto M, Xu X, Lu C, Shi Y, Yousaf N, Li J, Yien YY, Wei S. The RNA helicase DDX3 induces neural crest by promoting AKT activity. Development 2021; 148:dev.184341. [PMID: 33318149 DOI: 10.1242/dev.184341] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Accepted: 12/02/2020] [Indexed: 01/02/2023]
Abstract
Mutations in the RNA helicase DDX3 have emerged as a frequent cause of intellectual disability in humans. Because many individuals carrying DDX3 mutations have additional defects in craniofacial structures and other tissues containing neural crest (NC)-derived cells, we hypothesized that DDX3 is also important for NC development. Using Xenopus tropicalis as a model, we show that DDX3 is required for normal NC induction and craniofacial morphogenesis by regulating AKT kinase activity. Depletion of DDX3 decreases AKT activity and AKT-dependent inhibitory phosphorylation of GSK3β, leading to reduced levels of β-catenin and Snai1: two GSK3β substrates that are crucial for NC induction. DDX3 function in regulating these downstream signaling events during NC induction is likely mediated by RAC1, a small GTPase whose translation depends on the RNA helicase activity of DDX3. These results suggest an evolutionarily conserved role of DDX3 in NC development by promoting AKT activity, and provide a potential mechanism for the NC-related birth defects displayed by individuals harboring mutations in DDX3 and its downstream effectors in this signaling cascade.
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Affiliation(s)
- Mark Perfetto
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA.,Department of Biology, West Virginia University, Morgantown, WV 26506, USA
| | - Xiaolu Xu
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA
| | - Congyu Lu
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA
| | - Yu Shi
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA
| | - Natasha Yousaf
- Department of Biology, West Virginia University, Morgantown, WV 26506, USA
| | - Jiejing Li
- Department of Biology, West Virginia University, Morgantown, WV 26506, USA.,Department of Clinical Laboratory, The Affiliated Hospital of KMUST, Medical School, Kunming University of Science and Technology, Kunming 650032, China
| | - Yvette Y Yien
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA
| | - Shuo Wei
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA
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4
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Lambert FM, Cardoit L, Courty E, Bougerol M, Thoby-Brisson M, Simmers J, Tostivint H, Le Ray D. Functional limb muscle innervation prior to cholinergic transmitter specification during early metamorphosis in Xenopus. eLife 2018; 7:30693. [PMID: 29845935 PMCID: PMC5997451 DOI: 10.7554/elife.30693] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Accepted: 05/06/2018] [Indexed: 12/28/2022] Open
Abstract
In vertebrates, functional motoneurons are defined as differentiated neurons that are connected to a central premotor network and activate peripheral muscle using acetylcholine. Generally, motoneurons and muscles develop simultaneously during embryogenesis. However, during Xenopus metamorphosis, developing limb motoneurons must reach their target muscles through the already established larval cholinergic axial neuromuscular system. Here, we demonstrate that at metamorphosis onset, spinal neurons retrogradely labeled from the emerging hindlimbs initially express neither choline acetyltransferase nor vesicular acetylcholine transporter. Nevertheless, they are positive for the motoneuronal transcription factor Islet1/2 and exhibit intrinsic and axial locomotor-driven electrophysiological activity. Moreover, the early appendicular motoneurons activate developing limb muscles via nicotinic antagonist-resistant, glutamate antagonist-sensitive, neuromuscular synapses. Coincidently, the hindlimb muscles transiently express glutamate, but not nicotinic receptors. Subsequently, both pre- and postsynaptic neuromuscular partners switch definitively to typical cholinergic transmitter signaling. Thus, our results demonstrate a novel context-dependent re-specification of neurotransmitter phenotype during neuromuscular system development.
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Affiliation(s)
- Francois M Lambert
- Institut de Neurosciences Cognitives et Intégratives d'Aquitaine, Université de Bordeaux, Bordeaux, France
| | - Laura Cardoit
- Institut de Neurosciences Cognitives et Intégratives d'Aquitaine, Université de Bordeaux, Bordeaux, France
| | - Elric Courty
- Institut de Neurosciences Cognitives et Intégratives d'Aquitaine, Université de Bordeaux, Bordeaux, France
| | - Marion Bougerol
- Evolution des Régulations Endocriniennes, Muséum National d'Histoire Naturelle, Paris, France
| | - Muriel Thoby-Brisson
- Institut de Neurosciences Cognitives et Intégratives d'Aquitaine, Université de Bordeaux, Bordeaux, France
| | - John Simmers
- Institut de Neurosciences Cognitives et Intégratives d'Aquitaine, Université de Bordeaux, Bordeaux, France
| | - Hervé Tostivint
- Evolution des Régulations Endocriniennes, Muséum National d'Histoire Naturelle, Paris, France
| | - Didier Le Ray
- Institut de Neurosciences Cognitives et Intégratives d'Aquitaine, Université de Bordeaux, Bordeaux, France
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5
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Zhu X, Li Y, Meng Q. Islet-1 promotes the proliferation and invasion, and inhibits the apoptosis of A375 human melanoma cells. Int J Mol Med 2018; 41:3680-3690. [PMID: 29568936 DOI: 10.3892/ijmm.2018.3569] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Accepted: 03/12/2018] [Indexed: 11/06/2022] Open
Abstract
The aim of this study was to examine the effects of the insulin gene enhancer-binding protein, islet-1 (ISL1), on the proliferation, invasion and apoptosis of the human melanoma cell line, A375. An ISL1 overexpression lentiviral vector was constructed and transfected into the A375 cells. The proliferation of the A375 cells transfected with the ISL1 vector (termed A375/ISL1 cells) was examined by MTT assay, flow cytometry and TUNEL assay, and cell invasion was examined by Transwell assay. The expression levels of matrix metalloproteinase (MMP)-2 and MMP-9 were measured by qPCR and western blot analysis; the expression levels of Akt and p-Akt were measured in the cells treated with vascular endothelial growth factor (VEGF) and the PI3K/Akt inhibitor, LY294002, by western blot analysis. The optical density value of the A375/ISL1 cells was increased after 12 h of culture (P<0.001), as shown by MTT assay. The ratio of apoptotic A375/ISL1 cells was significantly decreased (P<0.001), as shown by flow cytometry and TUNEL assay. In addition, the average penetration rate of the A375/ISL1 cells significantly increased (P<0.001), as shown by Transwell assay. The expression levels of MMP-2 and MMP-9 were significantly increased in the A375/ISL1 cells, as shown by qPCR and western blot analysis (P<0.001). Moreover, treatment of the A375/ISL1 cells with VEGF for 48 h increased the expression of Akt and p-Akt compared with the control cells transfected with A375/green fluorescent protein (GFP) (P<0.05; P<0.001, respectively). In addition, in the A375/ISL1 cells treated with the LY294002 inhibitor for 24 and 48 h, the level of Akt was also found to increase compared to the control A375/GFP cells (P<0.05). On the whole, the findings of this study indicate that the overexpression of ISL1 promotes the proliferation and invasion, and inhibits the apoptosis of A375 melanoma cells. ISL1 thus plays an important role in A375 cell survival, and these effects are possibly mediate via the PI3K/Akt signaling pathway.
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Affiliation(s)
- Xiaoling Zhu
- Department of Dermatology, The First Hospital of Harbin, Harbin, Heilongjiang 150010, P.R. China
| | - Yuzhen Li
- Department of Dermatology, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150081, P.R. China
| | - Qinggang Meng
- Department of Orthopaedic Surgery, The First Hospital of Harbin, Harbin, Heilongjiang 150010, P.R. China
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6
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Shi Y, Li J, Chen C, Xia Y, Li Y, Zhang P, Xu Y, Li T, Zhou W, Song W. Ketamine Modulates Zic5 Expression via the Notch Signaling Pathway in Neural Crest Induction. Front Mol Neurosci 2018; 11:9. [PMID: 29472839 PMCID: PMC5810301 DOI: 10.3389/fnmol.2018.00009] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Accepted: 01/08/2018] [Indexed: 12/23/2022] Open
Abstract
Ketamine is a potent dissociative anesthetic and the most commonly used illicit drug. Many addicts are women at childbearing age. Although ketamine has been extensively studied as a clinical anesthetic, its effects on embryonic development are poorly understood. Here, we applied the Xenopus model to study the effects of ketamine on development. We found that exposure to ketamine from pre-gastrulation (stage 7) to early neural plate (stage 13.5) resulted in disruption of neural crest (NC) derivatives. Ketamine exposure did not affect mesoderm development as indicated by the normal expression of Chordin, Xbra, Wnt8, and Fgf8. However, ketamine treatment significantly inhibited Zic5 and Slug expression at early neural plate stage. Overexpression of Zic5 rescued ketamine-induced Slug inhibition, suggesting the blockage of NC induction was mediated by Zic5. Furthermore, we found Notch signaling was altered by ketamine. Ketamine inhibited the expression of Notch targeted genes including Hes5.2a, Hes5.2b, and ESR1 and ketamine-treated embryos exhibited Notch-deficient somite phenotypes. A 15 bp core binding element upstream of Zic5 was induced by Notch signaling and caused transcriptional activation. These results demonstrated that Zic5 works as a downstream target gene of Notch signaling in Xenopus NC induction. Our study provides a novel teratogenic mechanism whereby ketamine disrupts NC induction via targeting a Notch-Zic5 signaling pathway.
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Affiliation(s)
- Yu Shi
- Department of Clinical Laboratory, Children's Hospital of Chongqing Medical University, Chongqing, China.,Chongqing City Key Lab of Translational Medical Research in Cognitive Development and Learning and Memory Disorders and Ministry of Education Key Lab of Child Development and Disorders, Children's Hospital of Chongqing Medical University, Chongqing, China
| | - Jiejing Li
- Department of Clinical Laboratory, The Affiliated Hospital of KMUST, Medical School, Kunming University of Science and Technology, Kunming, China
| | - Chunjiang Chen
- Chongqing City Key Lab of Translational Medical Research in Cognitive Development and Learning and Memory Disorders and Ministry of Education Key Lab of Child Development and Disorders, Children's Hospital of Chongqing Medical University, Chongqing, China
| | - Yongwu Xia
- Department of Clinical Laboratory, Children's Hospital of Chongqing Medical University, Chongqing, China.,Chongqing City Key Lab of Translational Medical Research in Cognitive Development and Learning and Memory Disorders and Ministry of Education Key Lab of Child Development and Disorders, Children's Hospital of Chongqing Medical University, Chongqing, China
| | - Yanxi Li
- Chongqing City Key Lab of Translational Medical Research in Cognitive Development and Learning and Memory Disorders and Ministry of Education Key Lab of Child Development and Disorders, Children's Hospital of Chongqing Medical University, Chongqing, China
| | - Pan Zhang
- Chongqing City Key Lab of Translational Medical Research in Cognitive Development and Learning and Memory Disorders and Ministry of Education Key Lab of Child Development and Disorders, Children's Hospital of Chongqing Medical University, Chongqing, China.,Department of Anesthesiology, Children's Hospital of Chongqing Medical University, Chongqing, China
| | - Ying Xu
- Department of Anesthesiology, Children's Hospital of Chongqing Medical University, Chongqing, China
| | - Tingyu Li
- Chongqing City Key Lab of Translational Medical Research in Cognitive Development and Learning and Memory Disorders and Ministry of Education Key Lab of Child Development and Disorders, Children's Hospital of Chongqing Medical University, Chongqing, China
| | - Weihui Zhou
- Chongqing City Key Lab of Translational Medical Research in Cognitive Development and Learning and Memory Disorders and Ministry of Education Key Lab of Child Development and Disorders, Children's Hospital of Chongqing Medical University, Chongqing, China
| | - Weihong Song
- Chongqing City Key Lab of Translational Medical Research in Cognitive Development and Learning and Memory Disorders and Ministry of Education Key Lab of Child Development and Disorders, Children's Hospital of Chongqing Medical University, Chongqing, China.,Townsend Family Laboratories, Department of Psychiatry, The University of British Columbia, Vancouver, BC, Canada
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7
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Yang Z, Zhang Q, Lu Q, Jia Z, Chen P, Ma K, Wang W, Zhou C. ISL-1 promotes pancreatic islet cell proliferation by forming an ISL-1/Set7/9/PDX-1 complex. Cell Cycle 2016; 14:3820-9. [PMID: 26176407 PMCID: PMC4825718 DOI: 10.1080/15384101.2015.1069926] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Islet-1 (ISL-1), a LIM-homeodomain transcription factor, has been recently found to be essential for promoting postnatal pancreatic islet proliferation. However, the detailed mechanism has not yet been elucidated. In the present study, we investigated the mechanism by which ISL-1 promotes β-cell proliferation through regulation of CyclinD1 in HIT-T15 and NIT-1 cells, as well in rat islet mass. Our results provide the evidence that ISL-1 promotes adult pancreatic islet β-cell proliferation by activating CyclinD1 transcription through cooperation with Set7/9 and PDX-1 to form an ISL-1/Set7/9/PDX-1 complex. This complex functions in an ISL-1-dependent manner, with Set7/9 functioning not only as a histone methyltransferase, which increases the histone H3K4 tri-methylation of the CyclinD1 promoter region, but also an adaptor to bridge ISL-1 and PDX-1, while PDX-1 functions as a RNA pol II binding modulator. Furthermore, the formation of the ISL-1/Set7/9/PDX-1 complex is positively associated with insulin-like growth factor-1 treatment in NIT and HIT-T15 cells in vitro, while may be negatively correlated with age in vivo.
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Affiliation(s)
- Zhe Yang
- a Department of Biochemistry and Molecular Biology ; School of Basic Medical Sciences; Key Laboratory of Molecular Cardiovascular Sciences; Ministry of Education of China; Peking University ; Beijing , China
| | - Qiao Zhang
- a Department of Biochemistry and Molecular Biology ; School of Basic Medical Sciences; Key Laboratory of Molecular Cardiovascular Sciences; Ministry of Education of China; Peking University ; Beijing , China.,b Current address: Department of Biochemistry and Molecular Biology ; School of Basic Medical Sciences; Kunming Medical University ; Kunming , China
| | - Qin Lu
- a Department of Biochemistry and Molecular Biology ; School of Basic Medical Sciences; Key Laboratory of Molecular Cardiovascular Sciences; Ministry of Education of China; Peking University ; Beijing , China
| | - Zhuqing Jia
- a Department of Biochemistry and Molecular Biology ; School of Basic Medical Sciences; Key Laboratory of Molecular Cardiovascular Sciences; Ministry of Education of China; Peking University ; Beijing , China
| | - Ping Chen
- a Department of Biochemistry and Molecular Biology ; School of Basic Medical Sciences; Key Laboratory of Molecular Cardiovascular Sciences; Ministry of Education of China; Peking University ; Beijing , China
| | - Kangtao Ma
- a Department of Biochemistry and Molecular Biology ; School of Basic Medical Sciences; Key Laboratory of Molecular Cardiovascular Sciences; Ministry of Education of China; Peking University ; Beijing , China
| | - Weiping Wang
- a Department of Biochemistry and Molecular Biology ; School of Basic Medical Sciences; Key Laboratory of Molecular Cardiovascular Sciences; Ministry of Education of China; Peking University ; Beijing , China
| | - Chunyan Zhou
- a Department of Biochemistry and Molecular Biology ; School of Basic Medical Sciences; Key Laboratory of Molecular Cardiovascular Sciences; Ministry of Education of China; Peking University ; Beijing , China
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8
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Guo C, Wang W, Shi Q, Chen P, Zhou C. An abnormally high expression of ISL-1 represents a potential prognostic factor in gastric cancer. Hum Pathol 2015; 46:1282-9. [PMID: 26142548 DOI: 10.1016/j.humpath.2015.05.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2015] [Revised: 05/06/2015] [Accepted: 05/08/2015] [Indexed: 12/15/2022]
Abstract
Insulin gene enhancer binding protein-1 (ISL-1) is a transcription factor involved in development of the heart, motor neurons, and pancreas. Our previous study indicated that ISL-1 was overexpressed in gastric cancer but not in other gastrointestinal tumors. However, no immunohistochemical or clinicopathological studies of ISL-1 in gastric carcinoma have been performed. The aim of this study was to determine the expression and prognostic value of ISL-1 in gastric carcinoma. A nude mouse xenograft model was established to study the role of ISL-1 on cancer genesis and development in vivo. Overexpression of ISL-1 significantly enhanced the tumorigenicity of NIH3T3 cells in vivo. ISL-1 expression was evaluated using immunohistochemistry in 456 human gastric carcinoma and normal tissues. ISL-1 was significantly overexpressed in gastric adenocarcinoma compared with normal gastric tissues. ISL-1 expression was significantly associated with depth of invasion, lymph node metastasis, TNM stage, and histological grade (P < .05, χ(2) test). Positive ISL-1 expression was associated with poorer 5-year overall survival in gastric cancer (P = .001, log-rank test). Multivariate Cox regression analysis demonstrated that ISL-1 expression (P = .047) could be an independent prognostic factor for overall survival in gastric carcinoma. This study suggests that ISL-1 may be a useful prognostic biomarker and may represent a novel therapeutic target for gastric adenocarcinoma.
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Affiliation(s)
- Chen Guo
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Key Laboratory of Molecular Cardiovascular Sciences (Ministry of Education), Key Laboratory of Protein Posttranslational Modifications and Cell Function (Beijing), Peking University,38 Xue Yuan Rd, Beijing 100191, China.
| | - Weiping Wang
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Key Laboratory of Molecular Cardiovascular Sciences (Ministry of Education), Key Laboratory of Protein Posttranslational Modifications and Cell Function (Beijing), Peking University,38 Xue Yuan Rd, Beijing 100191, China.
| | - Qiong Shi
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Key Laboratory of Molecular Cardiovascular Sciences (Ministry of Education), Key Laboratory of Protein Posttranslational Modifications and Cell Function (Beijing), Peking University,38 Xue Yuan Rd, Beijing 100191, China.
| | - Ping Chen
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Key Laboratory of Molecular Cardiovascular Sciences (Ministry of Education), Key Laboratory of Protein Posttranslational Modifications and Cell Function (Beijing), Peking University,38 Xue Yuan Rd, Beijing 100191, China.
| | - Chunyan Zhou
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Key Laboratory of Molecular Cardiovascular Sciences (Ministry of Education), Key Laboratory of Protein Posttranslational Modifications and Cell Function (Beijing), Peking University,38 Xue Yuan Rd, Beijing 100191, China.
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9
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Ediger BN, Du A, Liu J, Hunter CS, Walp ER, Schug J, Kaestner KH, Stein R, Stoffers DA, May CL. Islet-1 Is essential for pancreatic β-cell function. Diabetes 2014; 63:4206-17. [PMID: 25028525 PMCID: PMC4237994 DOI: 10.2337/db14-0096] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Islet-1 (Isl-1) is essential for the survival and ensuing differentiation of pancreatic endocrine progenitors. Isl-1 remains expressed in all adult pancreatic endocrine lineages; however, its specific function in the postnatal pancreas is unclear. Here we determine whether Isl-1 plays a distinct role in the postnatal β-cell by performing physiological and morphometric analyses of a tamoxifen-inducible, β-cell-specific Isl-1 loss-of-function mouse: Isl-1(L/L); Pdx1-CreER(Tm). Ablating Isl-1 in postnatal β-cells reduced glucose tolerance without significantly reducing β-cell mass or increasing β-cell apoptosis. Rather, islets from Isl-1(L/L); Pdx1-CreER(Tm) mice showed impaired insulin secretion. To identify direct targets of Isl-1, we integrated high-throughput gene expression and Isl-1 chromatin occupancy using islets from Isl-1(L/L); Pdx1-CreER(Tm) mice and βTC3 insulinoma cells, respectively. Ablating Isl-1 significantly affected the β-cell transcriptome, including known targets Insulin and MafA as well as novel targets Pdx1 and Slc2a2. Using chromatin immunoprecipitation sequencing and luciferase reporter assays, we found that Isl-1 directly occupies functional regulatory elements of Pdx1 and Slc2a2. Thus Isl-1 is essential for postnatal β-cell function, directly regulates Pdx1 and Slc2a2, and has a mature β-cell cistrome distinct from that of pancreatic endocrine progenitors.
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Affiliation(s)
- Benjamin N Ediger
- Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia, Philadelphia, PA Department of Medicine and Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Aiping Du
- Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia, Philadelphia, PA
| | - Jingxuan Liu
- Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia, Philadelphia, PA
| | - Chad S Hunter
- Department of Molecular Physiology and Biophysics, Vanderbilt University Medical Center, Nashville, TN
| | - Erik R Walp
- Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia, Philadelphia, PA
| | - Jonathan Schug
- Department of Genetics and Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Klaus H Kaestner
- Department of Genetics and Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Roland Stein
- Department of Molecular Physiology and Biophysics, Vanderbilt University Medical Center, Nashville, TN
| | - Doris A Stoffers
- Department of Medicine and Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Catherine L May
- Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia, Philadelphia, PA Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA Janssen Research & Development, Spring House, PA
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10
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Li J, Li Y, Zhang P, Niu H, Shi Y. Nicotinic acid modulates intracellular calcium concentration and disassembles the cytoskeleton. Mol Med Rep 2014; 10:2805-10. [PMID: 25241762 PMCID: PMC4227433 DOI: 10.3892/mmr.2014.2576] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2013] [Accepted: 05/19/2014] [Indexed: 11/16/2022] Open
Abstract
Nicotinic acid (NA), a member of the vitamin B family, is well known for its functions in the treatment and prevention of atherosclerosis due to decreasing plasma levels of low-density lipoprotein cholesterol. In recent years, the major side effect of NA, cutaneous flushing, has also attracted extensive attention. However, the effects of NA in other aspects of physiology or cell biology have remained elusive. The present study provided evidence that high concentrations of NA were able to first reduce and later elevate intracellular [Ca2+] in the NIH3T3 cell line. The reduction of the intracellular Ca2+ concentration was achieved within the initial 10 sec, and was preceded by a gradual elevation of intracellular [Ca2+]. Notably, marked accumulation of opaque materials in the perinuclear region was observed in NIH3T3 cells treated with 70 mM NA. Further analysis revealed that treatment with 70 mM NA for 1 h disassembled the microtubule and F-actin cytoskeleton systems and resulted in β-tubulin degradation in an ubiquitin-proteasome-dependent manner. These data indicated that high concentrations of NA disrupted cytoskeleton structures, which may have contributed to minus end (nucleus region) to plus end (cell membrane region)-directed transport processes and resulted in the deposition of material in the perinuclear region. Artificially increasing [Ca2+] adding CaCl2 to the culture media effected the disassembly of F-actin, while it had no apparent effect on microtubules. These results suggested that the disruption of the cytoskeleton systems was not entirely due to the NA-induced elevation of [Ca2+]. Finally, microinjection of NA into xenopus embryos blocked the transport of melanosomes to the peripheral cellular area. In conclusion, the present study indicated that NA disassembles F-actin and microtubule systems, thereby blocking cytoskeleton-dependent intracellular transport.
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Affiliation(s)
- Jiejing Li
- Department of Clinical Laboratory, Children's Hospital of Chongqing Medical University, Chongqing 400014, P.R. China
| | - Yanxi Li
- Laboratory of Developmental Diseases in Childhood of Education Ministry, Key Laboratory of Pediatrics in Chongqing, Chongqing International Science and Technology Cooperation Center for Child Development and Disorder, Children's Hospital of Chongqing Medical University, Chongqing 400014, P.R. China
| | - Penghui Zhang
- Department of Clinical Laboratory, Children's Hospital of Chongqing Medical University, Chongqing 400014, P.R. China
| | - Hua Niu
- Clinical Laboratory Centre, The First People's Hospital of Yunnan Province, Kunming, Yunnan 650032, P.R. China
| | - Yu Shi
- Department of Clinical Laboratory, Children's Hospital of Chongqing Medical University, Chongqing 400014, P.R. China
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11
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Shi Y, Li J, Chen C, Gong M, Chen Y, Liu Y, Chen J, Li T, Song W. 5-Mehtyltetrahydrofolate rescues alcohol-induced neural crest cell migration abnormalities. Mol Brain 2014; 7:67. [PMID: 25223405 PMCID: PMC4172781 DOI: 10.1186/s13041-014-0067-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Accepted: 08/29/2014] [Indexed: 11/16/2022] Open
Abstract
Background Alcohol is detrimental to early development. Fetal alcohol spectrum disorders (FASD) due to maternal alcohol abuse results in a series of developmental abnormalities including cranial facial dysmorphology, ocular anomalies, congenital heart defects, microcephaly and intellectual disabilities. Previous studies have been shown that ethanol exposure causes neural crest (NC) apoptosis and perturbation of neural crest migration. However, the underlying mechanism remains elusive. In this report we investigated the fetal effect of alcohol on the process of neural crest development in the Xenopus leavis. Results Pre-gastrulation exposure of 2-4% alcohol induces apoptosis in Xenopus embryo whereas 1% alcohol specifically impairs neural crest migration without observing discernible apoptosis. Additionally, 1% alcohol treatment considerably increased the phenotype of small head (43.4% ± 4.4%, total embryo n = 234), and 1.5% and 2.0% dramatically augment the deformation to 81.2% ± 6.5% (n = 205) and 91.6% ± 3.0% (n = 235), respectively (P < 0.05). Significant accumulation of Homocysteine was caused by alcohol treatment in embryos and 5-mehtyltetrahydrofolate restores neural crest migration and alleviates homocysteine accumulation, resulting in inhibition of the alcohol-induced neurocristopathies. Conclusions Our study demonstrates that prenatal alcohol exposure causes neural crest cell migration abnormality and 5-mehtyltetrahydrofolate could be beneficial for treating FASD.
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12
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Moreno RL, Ribera AB. Spinal neurons require Islet1 for subtype-specific differentiation of electrical excitability. Neural Dev 2014; 9:19. [PMID: 25149090 PMCID: PMC4153448 DOI: 10.1186/1749-8104-9-19] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2013] [Accepted: 07/16/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND In the spinal cord, stereotypic patterns of transcription factor expression uniquely identify neuronal subtypes. These transcription factors function combinatorially to regulate gene expression. Consequently, a single transcription factor may regulate divergent development programs by participation in different combinatorial codes. One such factor, the LIM-homeodomain transcription factor Islet1, is expressed in the vertebrate spinal cord. In mouse, chick and zebrafish, motor and sensory neurons require Islet1 for specification of biochemical and morphological signatures. Little is known, however, about the role that Islet1 might play for development of electrical membrane properties in vertebrates. Here we test for a role of Islet1 in differentiation of excitable membrane properties of zebrafish spinal neurons. RESULTS We focus our studies on the role of Islet1 in two populations of early born zebrafish spinal neurons: ventral caudal primary motor neurons (CaPs) and dorsal sensory Rohon-Beard cells (RBs). We take advantage of transgenic lines that express green fluorescent protein (GFP) to identify CaPs, RBs and several classes of interneurons for electrophysiological study. Upon knock-down of Islet1, cells occupying CaP-like and RB-like positions continue to express GFP. With respect to voltage-dependent currents, CaP-like and RB-like neurons have novel repertoires that distinguish them from control CaPs and RBs, and, in some respects, resemble those of neighboring interneurons. The action potentials fired by CaP-like and RB-like neurons also have significantly different properties compared to those elicited from control CaPs and RBs. CONCLUSIONS Overall, our findings suggest that, for both ventral motor and dorsal sensory neurons, Islet1 directs differentiation programs that ultimately specify electrical membrane as well as morphological properties that act together to sculpt neuron identity.
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Affiliation(s)
- Rosa L Moreno
- Department of Physiology, University of Colorado Anschutz Medical Campus, RC-1 North, 7403A, Mailstop 8307, 12800 E 19th Ave,, 80045 Aurora, CO, USA.
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13
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Zhang Q, Yang Z, Wang W, Guo T, Jia Z, Ma K, Zhou C. A positive feedback regulation of ISL-1 in DLBCL but not in pancreatic β-cells. Biochem Biophys Res Commun 2014; 449:295-300. [PMID: 24845569 DOI: 10.1016/j.bbrc.2014.05.021] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2014] [Accepted: 05/09/2014] [Indexed: 12/12/2022]
Abstract
Insulin enhancer binding protein-1 (ISL-1), a LIM-homeodomain transcription factor, has been reported to play essential roles in promoting adult pancreatic β-cells proliferation. Recent studies indicate that ISL-1 may also involve in the occurrence of a variety of tumors. However, whether ISL-1 has any functional effect on tumorigenesis, and what are the differences on ISL-1 function in distinct conditions, are completely unknown. In this study, we found that ISL-1 was highly expressed in human pancreatic β-cells, as well as in diffuse large B cell lymphoma (DLBCL), but to a much less extent in other normal tissues or tumor specimens. Further study revealed that ISL-1 promoted the proliferation of pancreatic β-cells and DLBCL cells, and also accelerated the tumorigenesis of DLBCL in vivo. We also found that ISL-1 could activate c-Myc transcription not only in pancreatic β-cells but also in DLBCL cells. However, a cell-specific feedback regulation was detectable only in DLBCL cells. This auto-regulatory loop was established by the interaction of ISL-1 and c-Myc to form an ISL-1/c-Myc transcriptional complex, and synergistically to promote ISL-1 transcription through binding on the ISL-1 promoter. Taken together, our results demonstrate a positive feedback regulation of ISL-1 in DLBCL but not in pancreatic β-cells, which might result in the functional diversities of ISL-1 in different physiological and pathological processes.
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Affiliation(s)
- Qiao Zhang
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Key Laboratory of Molecular Cardiovascular Sciences (Ministry of Education), Peking University, 38 Xueyuan Road, 100191 Beijing, China.
| | - Zhe Yang
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Key Laboratory of Molecular Cardiovascular Sciences (Ministry of Education), Peking University, 38 Xueyuan Road, 100191 Beijing, China.
| | - Weiping Wang
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Key Laboratory of Molecular Cardiovascular Sciences (Ministry of Education), Peking University, 38 Xueyuan Road, 100191 Beijing, China.
| | - Ting Guo
- Department of Gastrointestinal Translation Research, Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Peking University Cancer Hospital, 52 Fucheng Road, 100142 Beijing, China.
| | - Zhuqing Jia
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Key Laboratory of Molecular Cardiovascular Sciences (Ministry of Education), Peking University, 38 Xueyuan Road, 100191 Beijing, China.
| | - Kangtao Ma
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Key Laboratory of Molecular Cardiovascular Sciences (Ministry of Education), Peking University, 38 Xueyuan Road, 100191 Beijing, China.
| | - Chunyan Zhou
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Key Laboratory of Molecular Cardiovascular Sciences (Ministry of Education), Peking University, 38 Xueyuan Road, 100191 Beijing, China.
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14
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Guo T, Wang W, Zhang H, Liu Y, Chen P, Ma K, Zhou C. ISL1 promotes pancreatic islet cell proliferation. PLoS One 2011; 6:e22387. [PMID: 21829621 PMCID: PMC3150357 DOI: 10.1371/journal.pone.0022387] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2011] [Accepted: 06/20/2011] [Indexed: 11/19/2022] Open
Abstract
Background Islet 1 (ISL1), a LIM-homeodomain transcription factor is essential for promoting pancreatic islets proliferation and maintaining endocrine cells survival in embryonic and postnatal pancreatic islets. However, how ISL1 exerts the role in adult islets is, to date, not clear. Methodology/Principal Findings Our results show that ISL1 expression was up-regulated at the mRNA level both in cultured pancreatic cells undergoing glucose oxidase stimulation as well in type 1 and type 2 diabetes mouse models. The knockdown of ISL1 expression increased the apoptosis level of HIT-T15 pancreatic islet cells. Using HIT-T15 and primary adult islet cells as cell models, we show that ISL1 promoted adult pancreatic islet cell proliferation with increased c-Myc and CyclinD1 transcription, while knockdown of ISL1 increased the proportion of cells in G1 phase and decreased the proportion of cells in G2/M and S phases. Further investigation shows that ISL1 activated both c-Myc and CyclinD1 transcription through direct binding on their promoters. Conclusions/Significance ISL1 promoted adult pancreatic islet cell proliferation and probably by activating c-Myc and CyclinD1 transcription through direct binding on their promoters. Our findings extend the knowledge about the crucial role of ISL1 in maintaining mature islet cells homeostasis. Our results also provide insights into the new regulation relationships between ISL1 and other growth factors.
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Affiliation(s)
- Ting Guo
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education of China, Peking University, Beijing, China
| | - Weiping Wang
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education of China, Peking University, Beijing, China
| | - Hui Zhang
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education of China, Peking University, Beijing, China
| | - Yinan Liu
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education of China, Peking University, Beijing, China
| | - Ping Chen
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education of China, Peking University, Beijing, China
| | - Kangtao Ma
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education of China, Peking University, Beijing, China
| | - Chunyan Zhou
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education of China, Peking University, Beijing, China
- * E-mail:
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15
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Ma P, Zhao S, Zeng W, Yang Q, Li C, Lv X, Zhou Q, Mao B. Xenopus Dbx2 is involved in primary neurogenesis and early neural plate patterning. Biochem Biophys Res Commun 2011; 412:170-4. [PMID: 21806971 DOI: 10.1016/j.bbrc.2011.07.068] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2011] [Accepted: 07/18/2011] [Indexed: 12/19/2022]
Abstract
The evolutionarily conserved Dbx homeodomain-containing proteins play important roles in the development of vertebrate central nervous system. In mouse, Dbx and Nkx6 have been suggested to be cross-repressive partners involved in the patterning of ventral neural tube. Here, we have isolated Xenopus Dbx2 and studied its developmental expression and function during neural development. Like XDbx1, from mid-neurula stage on, XDbx2 is expressed in stripes between the primary motoneurons and interneurons. At the tailbud stages, it is detected in the middle region of the neural tube. XDbx2 acts as a transcriptional repressor in vitro and over-expression of XDbx2 inhibits primary neurogenesis in Xenopus embryos. Over-expression of XDbx genes represses the expression of XNkx6.2 and vise versa. Knockdown of either XDbx1, XDbx2 or both by specific morpholinos induces lateral expansion of XNkx6.2 expression domains. These data reveal conserved roles for Dbx in primary neurogenesis and dorsoventral neural patterning in Xenopus.
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Affiliation(s)
- Pengcheng Ma
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China
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16
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Sîrbulescu RF, Zupanc GKH. Inhibition of caspase-3-mediated apoptosis improves spinal cord repair in a regeneration-competent vertebrate system. Neuroscience 2010; 171:599-612. [PMID: 20837106 DOI: 10.1016/j.neuroscience.2010.09.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2010] [Revised: 08/19/2010] [Accepted: 09/02/2010] [Indexed: 01/06/2023]
Abstract
Teleost fish exhibit an excellent potential for structural and functional recovery after CNS lesions. The function of apoptosis in the process of regeneration remains controversial. While some studies have identified this type of cell death as essential for successful regeneration, other investigations have suggested some degree of functional improvement after inhibition of apoptosis. In the present study, we examined whether inhibition of apoptosis immediately after injury can improve spinal cord regeneration. As a model system, we used Apteronotus leptorhynchus, a regeneration-competent weakly electric fish. To inhibit apoptosis, we employed 2,2'-methylenebis (1,3-cyclohexanedione) (M50054), a compound that prevents caspase-3 activation. Administration of this apoptosis inhibitor led to a significant reduction in the numbers of apoptotic cells at 24 h, 5 days, and 30 days after the lesion. Using triple immunolabeling, we identified a significant reduction in the level of apoptosis at 5 and 30 days after the lesion among the following cellular categories: cells generated shortly after the lesion, existing neurons, and newly differentiated neurons. This reduced rate of apoptosis led to an increase in the relative number of differentiating and surviving neurons at both 5 and 30 days post-injury, compared to the control groups. Functional regeneration, as indicated by the recovery rate of the amplitude of the electric organ discharge (EOD), was significantly improved within the first 20 days after the lesion in the fish treated with M50054. Our data provide the first evidence that modulation of caspase-3 activation can significantly improve neuroregeneration and functional recovery in a regeneration-competent organism.
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Affiliation(s)
- R F Sîrbulescu
- School of Engineering and Science, Jacobs University Bremen, P.O. BOX 750 561, 28725 Bremen, Germany
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Zeng W, Kong Q, Li C, Mao B. Xenopus RCOR2 (REST corepressor 2) interacts with ZMYND8, which is involved in neural differentiation. Biochem Biophys Res Commun 2010; 394:1024-9. [PMID: 20331974 DOI: 10.1016/j.bbrc.2010.03.115] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2010] [Accepted: 03/17/2010] [Indexed: 11/28/2022]
Abstract
Regulation of neuronal gene expression is critical to nervous system development. REST (RE1-silencing transcription factor) regulates neuronal gene expression through interacting with a group of corepressor proteins including REST corepressors (RCOR). Here we show that Xenopus RCOR2 is predominantly expressed in the developing nervous system. Through a yeast two-hybrid screen, we isolated Xenopus ZMYND8 (Zinc finger and MYND domain containing 8) as an XRCOR2 interacting factor. XRCOR2 and XZMYND8 bind each other in co-immunoprecipitation assays and both of them can function as transcriptional repressors. XZMYND8 is co-expressed with XRCOR2 in the nervous system and overexpression of XZMYND8 inhibits neural differentiation in Xenopus embryos. These data reveal a RCOR2/ZMYND8 complex which might be involved in the regulation of neural differentiation.
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Affiliation(s)
- Wanli Zeng
- CAS-Max Planck Junior Scientist Group on Developmental Biology, State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, 32 Jiaochang East Road, Kunming 650223, China
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