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Bou-Rouphael J, Doulazmi M, Eschstruth A, Abdou A, Durand BC. Cerebellar granular neuron progenitors exit their germinative niche via BarH-like1 activity mediated partly by inhibition of T-cell factor. Development 2024; 151:dev202234. [PMID: 38860486 DOI: 10.1242/dev.202234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2023] [Accepted: 06/04/2024] [Indexed: 06/12/2024]
Abstract
Cerebellar granule neuron progenitors (GNPs) originate from the upper rhombic lip (URL), a germinative niche in which developmental defects produce human diseases. T-cell factor (TCF) responsiveness and Notch dependence are hallmarks of self-renewal in neural stem cells. TCF activity, together with transcripts encoding proneural gene repressors hairy and enhancer of split (Hes/Hey), are detected in the URL; however, their functions and regulatory modes are undeciphered. Here, we established amphibian as a pertinent model for studying vertebrate URL development. The amphibian long-lived URL is TCF active, whereas the external granular layer (EGL) is non-proliferative and expresses hes4 and hes5 genes. Using functional and transcriptomic approaches, we show that TCF activity is necessary for URL emergence and maintenance. We establish that the transcription factor Barhl1 controls GNP exit from the URL, acting partly through direct TCF inhibition. Identification of Barhl1 target genes suggests that, besides TCF, Barhl1 inhibits transcription of hes5 genes independently of Notch signaling. Observations in amniotes suggest a conserved role for Barhl in maintenance of the URL and/or EGL via co-regulation of TCF, Hes and Hey genes.
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Affiliation(s)
- Johnny Bou-Rouphael
- Sorbonne Université, CNRS UMR7622, Institut de Biologie Paris-Seine (IBPS) - Laboratoire de Biologie du Développement, 75005 Paris, France
| | - Mohamed Doulazmi
- Sorbonne Université, CNRS UMR8256, Institut de Biologie Paris-Seine (IBPS) - Laboratoire Adaptation Biologique et Vieillissement, 75005 Paris, France
| | - Alexis Eschstruth
- Sorbonne Université, CNRS UMR7622, Institut de Biologie Paris-Seine (IBPS) - Laboratoire de Biologie du Développement, 75005 Paris, France
| | - Asna Abdou
- Sorbonne Université, CNRS UMR7622, Institut de Biologie Paris-Seine (IBPS) - Laboratoire de Biologie du Développement, 75005 Paris, France
| | - Béatrice C Durand
- Sorbonne Université, CNRS UMR7622, Institut de Biologie Paris-Seine (IBPS) - Laboratoire de Biologie du Développement, 75005 Paris, France
- Sorbonne Université, CNRS UMR8256, Institut de Biologie Paris-Seine (IBPS) - Laboratoire Adaptation Biologique et Vieillissement, 75005 Paris, France
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2
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McNerlin C, Guan F, Bronk L, Lei K, Grosshans D, Young DW, Gaber MW, Maletic-Savatic M. Targeting hippocampal neurogenesis to protect astronauts' cognition and mood from decline due to space radiation effects. LIFE SCIENCES IN SPACE RESEARCH 2022; 35:170-179. [PMID: 36336363 DOI: 10.1016/j.lssr.2022.07.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 06/30/2022] [Accepted: 07/26/2022] [Indexed: 06/16/2023]
Abstract
Neurogenesis is an essential, lifelong process during which neural stem cells generate new neurons within the hippocampus, a center for learning, memory, and mood control. Neural stem cells are vulnerable to environmental insults spanning from chronic stress to radiation. These insults reduce their numbers and diminish neurogenesis, leading to memory decline, anxiety, and depression. Preserving neural stem cells could thus help prevent these neurogenesis-associated pathologies, an outcome particularly important for long-term space missions where environmental exposure to radiation is significantly higher than on Earth. Multiple developments, from mechanistic discoveries of radiation injury on hippocampal neurogenesis to new platforms for the development of selective, specific, effective, and safe small molecules as neurogenesis-protective agents hold great promise to minimize radiation damage on neurogenesis. In this review, we summarize the effects of space-like radiation on hippocampal neurogenesis. We then focus on current advances in drug discovery and development and discuss the nuclear receptor TLX/NR2E1 (oleic acid receptor) as an example of a neurogenic target that might rescue neurogenesis following radiation.
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Affiliation(s)
- Clare McNerlin
- Georgetown University School of Medicine, 3900 Reservoir Rd NW, Washington D.C. 20007, United States of America
| | - Fada Guan
- Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT, 06510, United States of America
| | - Lawrence Bronk
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, United States of America
| | - Kevin Lei
- Graduate School for Biomedical Sciences, Baylor College of Medicine, Houston, Texas, 77030, United States of America; Jan and Dan Duncan Neurological Research Institute, 1250 Moursund St. Houston, TX 77030, United States of America
| | - David Grosshans
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, United States of America
| | - Damian W Young
- Jan and Dan Duncan Neurological Research Institute, 1250 Moursund St. Houston, TX 77030, United States of America; Center for Drug Discovery, Department of Pathology and Immunology Baylor College of Medicine, Houston, Texas, 77030, United States of America; Department of Pharmacology and Chemical Biology, Baylor College of Medicine, Houston, Texas 77030, United States of America
| | - M Waleed Gaber
- Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, United States of America.
| | - Mirjana Maletic-Savatic
- Jan and Dan Duncan Neurological Research Institute, 1250 Moursund St. Houston, TX 77030, United States of America; Department of Pediatrics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, United States of America; Department of Neuroscience, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, United States of America.
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3
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Neurogenesis in the adult brain functionally contributes to the maintenance of chronic neuropathic pain. Sci Rep 2021; 11:18549. [PMID: 34535707 PMCID: PMC8448753 DOI: 10.1038/s41598-021-97093-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Accepted: 07/29/2021] [Indexed: 02/06/2023] Open
Abstract
Maladaptive adult neurogenesis in the mammalian brain has been associated with diverse behaviors including disrupted learning, negative mood disorders and psychiatric conditions. However, its functional role in the generation and maintenance of chronic pathological pain has not yet been elucidated. Using an inducible genetic deletion in vivo mouse model, different behavioural paradigms and home cage monitoring systems, we show that an absence of adult neurogenesis does not impact the development of neuropathic injury-induced peripheral nociceptive hypersensitivity, but rather promotes the recovery of pathological pain as well as improves parameters associated with the state of well-being of the injured mice. These results provide a mechanistic insight into the mechanisms of chronic pain and implicate neurogenic processes as a potential therapeutic target for reducing pain and improving the quality of life for patients.
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4
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Neurogenesis of medium spiny neurons in the nucleus accumbens continues into adulthood and is enhanced by pathological pain. Mol Psychiatry 2021; 26:4616-4632. [PMID: 32612250 PMCID: PMC8589654 DOI: 10.1038/s41380-020-0823-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Revised: 05/28/2020] [Accepted: 06/15/2020] [Indexed: 12/11/2022]
Abstract
In mammals, most adult neural stem cells (NSCs) are located in the ventricular-subventricular zone (V-SVZ) along the wall of the lateral ventricles and they are the source of olfactory bulb interneurons. Adult NSCs exhibit an apico-basal polarity; they harbor a short apical process and a long basal process, reminiscent of radial glia morphology. In the adult mouse brain, we detected extremely long radial glia-like fibers that originate from the anterior-ventral V-SVZ and that are directed to the ventral striatum. Interestingly, a fraction of adult V-SVZ-derived neuroblasts dispersed in close association with the radial glia-like fibers in the nucleus accumbens (NAc). Using several in vivo mouse models, we show that newborn neurons integrate into preexisting circuits in the NAc where they mature as medium spiny neurons (MSNs), i.e., a type of projection neurons formerly believed to be generated only during embryonic development. Moreover, we found that the number of newborn neurons in the NAc is dynamically regulated by persistent pain, suggesting that adult neurogenesis of MSNs is an experience-modulated process.
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GPD1 Specifically Marks Dormant Glioma Stem Cells with a Distinct Metabolic Profile. Cell Stem Cell 2019; 25:241-257.e8. [DOI: 10.1016/j.stem.2019.06.004] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Revised: 03/15/2019] [Accepted: 06/07/2019] [Indexed: 12/26/2022]
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Mackeh R, Marr AK, Fadda A, Kino T. C2H2-Type Zinc Finger Proteins: Evolutionarily Old and New Partners of the Nuclear Hormone Receptors. NUCLEAR RECEPTOR SIGNALING 2018; 15:1550762918801071. [PMID: 30718982 PMCID: PMC6348741 DOI: 10.1177/1550762918801071] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Accepted: 02/02/2017] [Indexed: 12/21/2022]
Abstract
Nuclear hormone receptors (NRs) are evolutionarily conserved ligand-dependent
transcription factors. They are essential for human life, mediating the actions
of lipophilic molecules, such as steroid hormones and metabolites of fatty acid,
cholesterol, and external toxic compounds. The C2H2-type zinc finger proteins
(ZNFs) form the largest family of the transcription factors in humans and are
characterized by multiple, tandemly arranged zinc fingers. Many of the C2H2-type
ZNFs are conserved throughout evolution, suggesting their involvement in
preserved biological activities, such as general transcriptional regulation and
development/differentiation of organs/tissues observed in the early embryonic
phase. However, some C2H2-type ZNFs, such as those with the Krüppel-associated
box (KRAB) domain, appeared relatively late in evolution and have significantly
increased family members in mammals including humans, possibly modulating their
complicated transcriptional network and/or supporting the morphological
development/functions specific to them. Such evolutional characteristics of the
C2H2-type ZNFs indicate that these molecules influence the NR functions
conserved through evolution, whereas some also adjust them to meet with specific
needs of higher organisms. We review the interaction between NRs and C2H2-type
ZNFs by focusing on some of the latter molecules.
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7
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Liu H, Li G, Ma C, Chen Y, Wang J, Yang Y. Repetitive magnetic stimulation promotes the proliferation of neural progenitor cells via modulating the expression of miR-106b. Int J Mol Med 2018; 42:3631-3639. [PMID: 30320352 DOI: 10.3892/ijmm.2018.3922] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Accepted: 10/04/2018] [Indexed: 11/05/2022] Open
Abstract
Increasing evidence shows that repetitive transcranial magnetic stimulation (rTMS) promotes neurogenesis and the expression of microRNA (miR)‑106b. The present study investigated whether rTMS promotes the proliferation of neural progenitor cells (NPCs) and whether the effect is associated with the expression of miR‑106b. NPCs were cultured from the rat hippocampus and exposed to rTMS daily, comprising 1,000 stimuli for 3 days at 10 Hz, with 1.75 T output. The proliferation ability of the NPCs was revealed by EdU staining, and the levels of miR‑106b and downstream gene p21 in the NPCs were measured by reverse transcription‑quantitative polymerase chain reaction and western blot analyses. For analysis of the mechanism, the NPCs were transfected with Lenti‑miR‑106b or small interfering RNAs prior to rTMS. The results showed that: i) rTMS increased NPC proliferation, as revealed by the increased proportion of EdU‑positive cells; ii) rTMS was able to upregulate the expression of miR‑106b and downregulate the level of p21 in NPCs; iii) overexpression of miR‑106b further enhanced the effects of rTMS, whereas knockdown of miR‑106b had the opposite effects. Taken together, these data indicated that rTMS can promote NPC proliferation by upregulating the expression of miR‑106b and possibly inhibiting the expression of p21.
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Affiliation(s)
- Hua Liu
- College of Health Science, Wuhan Sports University, Wuhan, Hubei 430079, P.R. China
| | - Gaohua Li
- Graduate School, Wuhan Sports University, Wuhan, Hubei 430079, P.R. China
| | - Chunlian Ma
- College of Health Science, Wuhan Sports University, Wuhan, Hubei 430079, P.R. China
| | - Yanfang Chen
- Department of Pharmacology and Toxicology, Boonshoft School of Medicine, Wright State University, Dayton, OH 45435, USA
| | - Jinju Wang
- Department of Pharmacology and Toxicology, Boonshoft School of Medicine, Wright State University, Dayton, OH 45435, USA
| | - Yi Yang
- College of Health Science, Wuhan Sports University, Wuhan, Hubei 430079, P.R. China
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8
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Ubiquitination of nuclear receptors. Clin Sci (Lond) 2017; 131:917-934. [PMID: 28473472 DOI: 10.1042/cs20160708] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Revised: 01/26/2017] [Accepted: 01/31/2017] [Indexed: 12/17/2022]
Abstract
Nuclear receptors (NRs) are cellular proteins, which upon ligand activation, act to exert regulatory control over transcription and subsequent expression. Organized via systemic classification into seven subfamilies, NRs partake in modulating a vast expanse of physiological functions essential for maintenance of life. NRs display particular characteristics towards ubiquitination, the process of addition of specific ubiquitin tags at appropriate locations. Orchestrated through groups of enzymes harboring a diverse array of specialized structural components, the ubiquitination process emphatically alters the fate or downstream effects of NRs. Such influence is especially prominent in transcriptional processes such as promoter clearing for optimization and degradation pathways eliminating or recycling targeted proteins. Ultimately, the ubiquitination of NRs carries significant implications in terms of generating pathological clinical manifestations. Increasing evidence from studies involving patients and disease models suggests a role for ubiquitinated NRs in virtually every organ system. This supports the broad repertoire of roles that NRs play in the body, including modulatory conductors, facilitators, responders to external agents, and critical constituents for pharmacological or biological interventions. This review aims to cover relevant background and mechanisms of NRs and ubiquitination, with a focus towards elucidating subsequent pathophysiology and therapeutics in clinical disorders encompassing such ubiquitinated NRs.
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9
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Hiramatsu H, Kobayashi K, Kobayashi K, Haraguchi T, Ino Y, Todo T, Iba H. The role of the SWI/SNF chromatin remodeling complex in maintaining the stemness of glioma initiating cells. Sci Rep 2017; 7:889. [PMID: 28420882 PMCID: PMC5429847 DOI: 10.1038/s41598-017-00982-3] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Accepted: 03/17/2017] [Indexed: 12/20/2022] Open
Abstract
Glioma initiating cells (GICs) are thought to contribute to therapeutic resistance and tumor recurrence in glioblastoma, a lethal primary brain tumor in adults. Although the stem-like properties of GICs, such as self-renewal and tumorigenicity, are epigenetically regulated, the role of a major chromatin remodeling complex in human, the SWI/SNF complex, remains unknown in these cells. We here demonstrate that the SWI/SNF core complex, that is associated with a unique corepressor complex through the d4-family proteins, DPF1 or DPF3a, plays essential roles in stemness maintenance in GICs. The serum-induced differentiation of GICs downregulated the endogenous expression of DPF1 and DPF3a, and the shRNA-mediated knockdown of each gene reduced both sphere-forming ability and tumor-forming activity in a mouse xenograft model. Rescue experiments revealed that DPF1 has dominant effects over DPF3a. Notably, whereas we have previously reported that d4-family members can function as adaptor proteins between the SWI/SNF complex and NF-κB dimers, this does not significantly contribute to maintaining the stemness properties of GICs. Instead, these proteins were found to link a corepressor complex containing the nuclear receptor, TLX, and LSD1/RCOR2 with the SWI/SNF core complex. Collectively, our results indicate that DPF1 and DPF3a are potential therapeutic targets for glioblastoma.
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Affiliation(s)
- Hiroaki Hiramatsu
- Division of Host-Parasite Interaction, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, Tokyo, 108-8639, Japan
- Division of RNA Therapy, Medical Mycology Research Center, Chiba University, Chiba, 260-8673, Japan
| | - Kazuyoshi Kobayashi
- Division of Host-Parasite Interaction, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, Tokyo, 108-8639, Japan
- Division of RNA Therapy, Medical Mycology Research Center, Chiba University, Chiba, 260-8673, Japan
| | - Kyousuke Kobayashi
- Division of Host-Parasite Interaction, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, Tokyo, 108-8639, Japan
| | - Takeshi Haraguchi
- Division of Host-Parasite Interaction, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, Tokyo, 108-8639, Japan
- Division of RNA Therapy, Medical Mycology Research Center, Chiba University, Chiba, 260-8673, Japan
| | - Yasushi Ino
- Division of Innovative Cancer Therapy, and Department of Surgical Neuro-Oncology, The Institute of Medical Science, The University of Tokyo, Tokyo, 108-8639, Japan
| | - Tomoki Todo
- Division of Innovative Cancer Therapy, and Department of Surgical Neuro-Oncology, The Institute of Medical Science, The University of Tokyo, Tokyo, 108-8639, Japan
| | - Hideo Iba
- Division of Host-Parasite Interaction, Department of Microbiology and Immunology, The Institute of Medical Science, The University of Tokyo, Tokyo, 108-8639, Japan.
- Division of RNA Therapy, Medical Mycology Research Center, Chiba University, Chiba, 260-8673, Japan.
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10
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Nonaka S, Ando Y, Kanetani T, Hoshi C, Nakai Y, Nainu F, Nagaosa K, Shiratsuchi A, Nakanishi Y. Signaling pathway for phagocyte priming upon encounter with apoptotic cells. J Biol Chem 2017; 292:8059-8072. [PMID: 28325838 DOI: 10.1074/jbc.m116.769745] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2016] [Revised: 03/12/2017] [Indexed: 12/18/2022] Open
Abstract
The phagocytic elimination of cells undergoing apoptosis is an evolutionarily conserved innate immune mechanism for eliminating unnecessary cells. Previous studies showed an increase in the level of engulfment receptors in phagocytes after the phagocytosis of apoptotic cells, which leads to the enhancement of their phagocytic activity. However, precise mechanisms underlying this phenomenon require further clarification. We found that the pre-incubation of a Drosophila phagocyte cell line with the fragments of apoptotic cells enhanced the subsequent phagocytosis of apoptotic cells, accompanied by an augmented expression of the engulfment receptors Draper and integrin αPS3. The DNA-binding activity of the transcription repressor Tailless was transiently raised in those phagocytes, depending on two partially overlapping signal-transduction pathways for the induction of phagocytosis as well as the occurrence of engulfment. The RNAi knockdown of tailless in phagocytes abrogated the enhancement of both phagocytosis and engulfment receptor expression. Furthermore, the hemocyte-specific RNAi of tailless reduced apoptotic cell clearance in Drosophila embryos. Taken together, we propose the following mechanism for the activation of Drosophila phagocytes after an encounter with apoptotic cells: two partially overlapping signal-transduction pathways for phagocytosis are initiated; transcription repressor Tailless is activated; expression of engulfment receptors is stimulated; and phagocytic activity is enhanced. This phenomenon most likely ensures the phagocytic elimination of apoptotic cells by stimulated phagocytes and is thus considered as a mechanism to prime phagocytes in innate immunity.
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Affiliation(s)
- Saori Nonaka
- From the Graduate School of Medical Sciences and
| | - Yuki Ando
- From the Graduate School of Medical Sciences and
| | | | - Chiharu Hoshi
- School of Pharmacy, Kanazawa University, Kanazawa, Ishikawa 920-1192, Japan
| | - Yuji Nakai
- the Institute for Food Sciences, Hirosaki University, Aomori, Aomori 038-0012, Japan, and
| | - Firzan Nainu
- From the Graduate School of Medical Sciences and.,the Faculty of Pharmacy, Hasanuddin University, Makassar, South Sulawesi 90245, Indonesia
| | - Kaz Nagaosa
- the Institute for Food Sciences, Hirosaki University, Aomori, Aomori 038-0012, Japan, and
| | | | - Yoshinobu Nakanishi
- From the Graduate School of Medical Sciences and .,School of Pharmacy, Kanazawa University, Kanazawa, Ishikawa 920-1192, Japan
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11
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O'Leary JD, O'Leary OF, Cryan JF, Nolan YM. Regulation of behaviour by the nuclear receptor TLX. GENES BRAIN AND BEHAVIOR 2016; 17:e12357. [PMID: 27790850 DOI: 10.1111/gbb.12357] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Revised: 09/15/2016] [Accepted: 10/25/2016] [Indexed: 01/10/2023]
Abstract
The orphan nuclear receptor Tlx (Nr2e1) is a key regulator of both embryonic and adult hippocampal neurogenesis. Several different mouse models have been developed which target Tlx in vivo including spontaneous deletion models (from birth) and targeted and conditional knockouts. Although some conflicting findings have been reported, for the most part studies have demonstrated that Tlx is important in regulating processes that underlie neurogenesis, spatial learning, anxiety-like behaviour and interestingly, aggression. More recent data have demonstrated that disrupting Tlx during early life induces hyperactivity and that Tlx plays a role in emotional regulation. Moreover, there are sex- and age-related differences in some behaviours in Tlx knockout mice during adolescence and adulthood. Here, we discuss the role of Tlx in motor-, cognitive-, aggressive- and anxiety-related behaviours during adolescence and adulthood. We examine current evidence which provides insight into Tlx during neurodevelopment, and offer our thoughts on the function of Tlx in brain and behaviour. We further hypothesize that Tlx is a key target in understanding the emergence of neurobiological disorders during adolescence and early adulthood.
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Affiliation(s)
- J D O'Leary
- Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland
| | - O F O'Leary
- Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland.,APC Microbiome Institute, University College Cork, Cork, Ireland
| | - J F Cryan
- Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland.,APC Microbiome Institute, University College Cork, Cork, Ireland
| | - Y M Nolan
- Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland
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12
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Sobhan PK, Zhai Q, Green LC, Hansford LM, Funa K. ASK1 regulates the survival of neuroblastoma cells by interacting with TLX and stabilizing HIF-1α. Cell Signal 2016; 30:104-117. [PMID: 27890558 DOI: 10.1016/j.cellsig.2016.11.018] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2016] [Revised: 11/10/2016] [Accepted: 11/21/2016] [Indexed: 12/13/2022]
Abstract
Elevated expression of TLX (also called as NR2E1) in neuroblastoma (NB) correlates with unfavorable prognosis, and TLX is required for self-renewal of NB cells. Knockdown of TLX has been shown to reduce the NB sphere-forming ability. ASK1 (MAP3K5) and TLX expression are both enhanced in SP (side population) NB and patient-derived primary NB sphere cell lines, but the majority of non-SP NB lines express lower ASK1 expression. We found that ASK1 phosphorylated and stabilized TLX, which led induction of HIF-1α, and its downstream VEGF-A in an Akt dependent manner. In depleting ASK1 upon hypoxia, TLX decreased and the apoptosis ratio of NB cells was enhanced, while low-ASK1-expressing NB cell lines were refractory in TUNEL assay by using flow cytometry. Interestingly, primary NB spheres cell lines express only high levels of active pASK1Thr-838 but the established cell lines expressed inhibitory pASK1Ser-966, and both could be targeted by ASK1 depletion. We report a novel pro-survival role of ASK1 in the tumorigenic NB cell populations, which may be applied as a therapeutic target, inducing apoptosis specifically in cancer stem cells.
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Affiliation(s)
- Praveen K Sobhan
- Sahlgrenska Cancer Center, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, SE 405 30 Gothenburg, Sweden.
| | - Qiwei Zhai
- Sahlgrenska Cancer Center, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, SE 405 30 Gothenburg, Sweden.
| | - Lydia C Green
- Sahlgrenska Cancer Center, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, SE 405 30 Gothenburg, Sweden.
| | - Loen M Hansford
- Program in Neurosciences and Mental Health, The Hospital for Sick Children, University of Toronto, Toronto, Canada.
| | - Keiko Funa
- Sahlgrenska Cancer Center, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, SE 405 30 Gothenburg, Sweden; Oncology Laboratory, Department of Pathology, Sahlgrenska University Hospital, SE 413 45 Gothenburg, Sweden.
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13
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Enhancer Analysis Unveils Genetic Interactions between TLX and SOX2 in Neural Stem Cells and In Vivo Reprogramming. Stem Cell Reports 2016; 5:805-815. [PMID: 26607952 PMCID: PMC4649261 DOI: 10.1016/j.stemcr.2015.09.015] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Revised: 09/16/2015] [Accepted: 09/17/2015] [Indexed: 12/26/2022] Open
Abstract
The orphan nuclear receptor TLX is a master regulator of postnatal neural stem cell (NSC) self-renewal and neurogenesis; however, it remains unclear how TLX expression is precisely regulated in these tissue-specific stem cells. Here, we show that a highly conserved cis-element within the Tlx locus functions to drive gene expression in NSCs. We demonstrate that the transcription factors SOX2 and MYT1 specifically interact with this genomic element to directly regulate Tlx enhancer activity in vivo. Knockdown experiments further reveal that SOX2 dominantly controls endogenous expression of TLX, whereas MYT1 only plays a modulatory role. Importantly, TLX is essential for SOX2-mediated in vivo reprogramming of astrocytes and itself is also sufficient to induce neurogenesis in the adult striatum. Together, these findings unveil functional genetic interactions among transcription factors that are critical to NSCs and in vivo cell reprogramming. An evolutionarily conserved enhancer drives Tlx expression in neural stem cells SOX2 directly activates the identified enhancer and Tlx expression SOX2-mediated in vivo reprogramming of astrocytes to neuroblasts requires TLX
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14
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Wang T, Xiong JQ. The Orphan Nuclear Receptor TLX/NR2E1 in Neural Stem Cells and Diseases. Neurosci Bull 2016; 32:108-14. [PMID: 26769490 DOI: 10.1007/s12264-015-0004-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2015] [Accepted: 09/26/2015] [Indexed: 12/24/2022] Open
Abstract
The human TLX gene encodes an orphan nuclear receptor predominantly expressed in the central nervous system. Tailess and Tlx, the TLX homologues in Drosophila and mouse, play essential roles in body-pattern formation and neurogenesis during early embryogenesis and perform crucial functions in maintaining stemness and controlling the differentiation of adult neural stem cells in the central nervous system, especially the visual system. Multiple target genes and signaling pathways are regulated by TLX and its homologues in specific tissues during various developmental stages. This review aims to summarize previous studies including many recent updates from different aspects concerning TLX and its homologues in Drosophila and mouse.
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Affiliation(s)
- Tao Wang
- Department of Intensive Care, Southwest Hospital, Third Military Medical University, Chongqing, 400038, China
| | - Jian-Qiong Xiong
- Department of Intensive Care, Southwest Hospital, Third Military Medical University, Chongqing, 400038, China.
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TLX-Its Emerging Role for Neurogenesis in Health and Disease. Mol Neurobiol 2016; 54:272-280. [PMID: 26738856 PMCID: PMC5219886 DOI: 10.1007/s12035-015-9608-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Accepted: 12/03/2015] [Indexed: 02/07/2023]
Abstract
The orphan nuclear receptor TLX, also called NR2E1, is a factor important in the regulation of neural stem cell (NSC) self-renewal, neurogenesis, and maintenance. As a transcription factor, TLX is vital for the expression of genes implicated in neurogenesis, such as DNA replication, cell cycle, adhesion and migration. It acts by way of repressing or activating target genes, as well as controlling protein-protein interactions. Growing evidence suggests that dysregulated TLX acts in the initiation and progression of human disorders of the nervous system. This review describes recent knowledge about TLX expression, structure, targets, and biological functions, relevant to maintaining adult neural stem cells related to both neuropsychiatric conditions and certain nervous system tumours.
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Islam MM, Zhang CL. TLX: A master regulator for neural stem cell maintenance and neurogenesis. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2014; 1849:210-6. [PMID: 24930777 DOI: 10.1016/j.bbagrm.2014.06.001] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2014] [Revised: 04/22/2014] [Accepted: 06/05/2014] [Indexed: 10/25/2022]
Abstract
The orphan nuclear receptor TLX, also known as NR2E1, is an essential regulator of neural stem cell (NSC) self-renewal, maintenance, and neurogenesis. In vertebrates, TLX is specifically localized to the neurogenic regions of the forebrain and retina throughout development and adulthood. TLX regulates the expression of genes involved in multiple pathways, such as the cell cycle, DNA replication, and cell adhesion. These roles are primarily performed through the transcriptional repression or activation of downstream target genes. Emerging evidence suggests that the misregulation of TLX might play a role in the onset and progression of human neurological disorders making this factor an ideal therapeutic target. Here, we review the current understanding of TLX function, expression, regulation, and activity significant to NSC maintenance, adult neurogenesis, and brain plasticity. This article is part of a Special Issue entitled: Nuclear receptors in animal development.
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Affiliation(s)
- Mohammed M Islam
- Department of Molecular Biology, 6000 Harry Hines Blvd., Dallas, TX 75390, USA
| | - Chun-Li Zhang
- Department of Molecular Biology, 6000 Harry Hines Blvd., Dallas, TX 75390, USA.
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Ogundele OM, Omoaghe AO, Ajonijebu DC, Ojo AA, Fabiyi TD, Olajide OJ, Falode DT, Adeniyi PA. Glia activation and its role in oxidative stress. Metab Brain Dis 2014; 29:483-93. [PMID: 24218104 DOI: 10.1007/s11011-013-9446-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2013] [Accepted: 10/21/2013] [Indexed: 12/24/2022]
Abstract
Glia activation and neuroinflamation are major factors implicated in the aetiology of most neurodegenerative diseases (NDDs). Several agents and toxins have been known to be capable of inducing glia activation an inflammatory response; most of which are active substances that can cause oxidative stress by inducing production of reactive oxygen species (ROS). Neurogenesis on the other hand involves metabolic and structural interaction between neurogenic and glia cells of the periventricular zone (PVZ); a region around the third ventricle. This study investigates glia activation (GFAP), cell proliferation (Ki-67) and neuronal metabolism (NSE) during neurogenesis and oxidative stress by comparing protein expression in the PVZ against that of the parietal cortex. Adult Wistar Rats were treated with normal saline and 20 mg/Kg KCN for 7 days. The tissue sections were processed for immunohistochemistry to demonstrate glia cells (anti Rat-GFAP), cell proliferation (anti Rat-Ki-67) and neuronal metabolism (anti Rat-NSE) using the antigen retrieval method. The sections from Rats treated with cyanide showed evidence of neurodegeneration both in the PVZ and cortex. The distribution of glia cells (GFAP), Neuron specific Enolase (NSE) and Ki-67 increased with cyanide treatment, although the increases were more pronounced in the neurogenic cell area (PVZ) when compared to the cortex. This suggests the close link between neuronal metabolism and glia activation both in neurogenesis and oxidative stress.
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Affiliation(s)
- Olalekan Michael Ogundele
- Department of Anatomy, College of Medicine and Health Sciences, Afe Babalola University, Ado-Ekiti, Nigeria,
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