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Khudayberdiev S, Weiss K, Heinze A, Colombaretti D, Trausch N, Linne U, Rust MB. The actin-binding protein CAP1 represses MRTF-SRF-dependent gene expression in mouse cerebral cortex. Sci Signal 2024; 17:eadj0032. [PMID: 38713765 DOI: 10.1126/scisignal.adj0032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Accepted: 04/15/2024] [Indexed: 05/09/2024]
Abstract
Serum response factor (SRF) is an essential transcription factor for brain development and function. Here, we explored how an SRF cofactor, the actin monomer-sensing myocardin-related transcription factor MRTF, is regulated in mouse cortical neurons. We found that MRTF-dependent SRF activity in vitro and in vivo was repressed by cyclase-associated protein CAP1. Inactivation of the actin-binding protein CAP1 reduced the amount of actin monomers in the cytoplasm, which promoted nuclear MRTF translocation and MRTF-SRF activation. This function was independent of cofilin1 and actin-depolymerizing factor, and CAP1 loss of function in cortical neurons was not compensated by endogenous CAP2. Transcriptomic and proteomic analyses of cerebral cortex lysates from wild-type and Cap1 knockout mice supported the role of CAP1 in repressing MRTF-SRF-dependent signaling in vivo. Bioinformatic analysis identified likely MRTF-SRF target genes, which aligned with the transcriptomic and proteomic results. Together with our previous studies that implicated CAP1 in axonal growth cone function as well as the morphology and plasticity of excitatory synapses, our findings establish CAP1 as a crucial actin regulator in the brain relevant for formation of neuronal networks.
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Affiliation(s)
- Sharof Khudayberdiev
- Molecular Neurobiology Group, Institute of Physiological Chemistry, Philipps-University of Marburg, 35032 Marburg, Germany
- Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus-Liebig-University Giessen, Hans-Meerwein-Strasse 6, 35032 Marburg, Germany
| | - Kerstin Weiss
- Molecular Neurobiology Group, Institute of Physiological Chemistry, Philipps-University of Marburg, 35032 Marburg, Germany
| | - Anika Heinze
- Molecular Neurobiology Group, Institute of Physiological Chemistry, Philipps-University of Marburg, 35032 Marburg, Germany
| | - Dalila Colombaretti
- Molecular Neurobiology Group, Institute of Physiological Chemistry, Philipps-University of Marburg, 35032 Marburg, Germany
| | - Nathan Trausch
- Molecular Neurobiology Group, Institute of Physiological Chemistry, Philipps-University of Marburg, 35032 Marburg, Germany
| | - Uwe Linne
- Department of Chemistry, Philipps-University Marburg, 35032 Marburg, Germany
| | - Marco B Rust
- Molecular Neurobiology Group, Institute of Physiological Chemistry, Philipps-University of Marburg, 35032 Marburg, Germany
- Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus-Liebig-University Giessen, Hans-Meerwein-Strasse 6, 35032 Marburg, Germany
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2
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Iram T, Garcia MA, Amand J, Kaur A, Atkins M, Iyer M, Lam M, Ambiel N, Jorgens DM, Keller A, Wyss-Coray T, Kern F, Zuchero JB. SRF transcriptionally regulates the oligodendrocyte cytoskeleton during CNS myelination. Proc Natl Acad Sci U S A 2024; 121:e2307250121. [PMID: 38483990 PMCID: PMC10962977 DOI: 10.1073/pnas.2307250121] [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: 05/10/2023] [Accepted: 02/10/2024] [Indexed: 03/19/2024] Open
Abstract
Myelination of neuronal axons is essential for nervous system development. Myelination requires dramatic cytoskeletal dynamics in oligodendrocytes, but how actin is regulated during myelination is poorly understood. We recently identified serum response factor (SRF)-a transcription factor known to regulate expression of actin and actin regulators in other cell types-as a critical driver of myelination in the aged brain. Yet, a major gap remains in understanding the mechanistic role of SRF in oligodendrocyte lineage cells. Here, we show that SRF is required cell autonomously in oligodendrocytes for myelination during development. Combining ChIP-seq with RNA-seq identifies SRF-target genes in oligodendrocyte precursor cells and oligodendrocytes that include actin and other key cytoskeletal genes. Accordingly, SRF knockout oligodendrocytes exhibit dramatically reduced actin filament levels early in differentiation, consistent with its role in actin-dependent myelin sheath initiation. Surprisingly, oligodendrocyte-restricted loss of SRF results in upregulation of gene signatures associated with aging and neurodegenerative diseases. Together, our findings identify SRF as a transcriptional regulator that controls the expression of cytoskeletal genes required in oligodendrocytes for myelination. This study identifies an essential pathway regulating oligodendrocyte biology with high relevance to brain development, aging, and disease.
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Affiliation(s)
- Tal Iram
- Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, CA94305
- Wu Tsai Neurosciences Institute, Stanford University School of Medicine, Stanford, CA94305
| | - Miguel A. Garcia
- Department of Neurosurgery, Stanford University School of Medicine, Stanford, CA94305
| | - Jérémy Amand
- Department of Clinical Bioinformatics, Helmholtz Institute for Pharmaceutical Research Saarland–Helmholtz Centre for Infection Research, Saarland University Campus, Saarbrücken66123, Germany
- Clinical Bioinformatics, Saarland University, Saarbrücken66123, Germany
| | - Achint Kaur
- Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, CA94305
- Wu Tsai Neurosciences Institute, Stanford University School of Medicine, Stanford, CA94305
| | - Micaiah Atkins
- Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, CA94305
- Wu Tsai Neurosciences Institute, Stanford University School of Medicine, Stanford, CA94305
| | - Manasi Iyer
- Department of Neurosurgery, Stanford University School of Medicine, Stanford, CA94305
| | - Mable Lam
- Department of Neurosurgery, Stanford University School of Medicine, Stanford, CA94305
| | - Nicholas Ambiel
- Department of Neurosurgery, Stanford University School of Medicine, Stanford, CA94305
| | | | - Andreas Keller
- Department of Clinical Bioinformatics, Helmholtz Institute for Pharmaceutical Research Saarland–Helmholtz Centre for Infection Research, Saarland University Campus, Saarbrücken66123, Germany
- Clinical Bioinformatics, Saarland University, Saarbrücken66123, Germany
| | - Tony Wyss-Coray
- Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, CA94305
- Wu Tsai Neurosciences Institute, Stanford University School of Medicine, Stanford, CA94305
| | - Fabian Kern
- Department of Clinical Bioinformatics, Helmholtz Institute for Pharmaceutical Research Saarland–Helmholtz Centre for Infection Research, Saarland University Campus, Saarbrücken66123, Germany
- Clinical Bioinformatics, Saarland University, Saarbrücken66123, Germany
| | - J. Bradley Zuchero
- Department of Neurosurgery, Stanford University School of Medicine, Stanford, CA94305
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Song J, Dikwella N, Sinske D, Roselli F, Knöll B. SRF deletion results in earlier disease onset in a mouse model of amyotrophic lateral sclerosis. JCI Insight 2023; 8:e167694. [PMID: 37339001 PMCID: PMC10445689 DOI: 10.1172/jci.insight.167694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Accepted: 06/16/2023] [Indexed: 06/22/2023] Open
Abstract
Changes in neuronal activity modulate the vulnerability of motoneurons (MNs) in neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS). So far, the molecular basis of neuronal activity's impact in ALS is poorly understood. Herein, we investigated the impact of deleting the neuronal activity-stimulated transcription factor (TF) serum response factor (SRF) in MNs of SOD1G93A mice. SRF was present in vulnerable MMP9+ MNs. Ablation of SRF in MNs induced an earlier disease onset starting around 7-8 weeks after birth, as revealed by enhanced weight loss and decreased motor ability. This earlier disease onset in SRF-depleted MNs was accompanied by a mild elevation of neuroinflammation and neuromuscular synapse degeneration, whereas overall MN numbers and mortality were unaffected. In SRF-deficient mice, MNs showed impaired induction of autophagy-encoding genes, suggesting a potentially new SRF function in transcriptional regulation of autophagy. Complementary, constitutively active SRF-VP16 enhanced autophagy-encoding gene transcription and autophagy progression in cells. Furthermore, SRF-VP16 decreased ALS-associated aggregate induction. Chemogenetic modulation of neuronal activity uncovered SRF as having important TF-mediating activity-dependent effects, which might be beneficial to reduce ALS disease burden. Thus, our data identify SRF as a gene regulator connecting neuronal activity with the cellular autophagy program initiated in degenerating MNs.
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Affiliation(s)
- Jialei Song
- Institute of Neurobiochemistry and
- Department of Neurology, Ulm University, Ulm, Germany
| | - Natalie Dikwella
- Institute of Neurobiochemistry and
- Department of Neurology, Ulm University, Ulm, Germany
| | | | - Francesco Roselli
- Department of Neurology, Ulm University, Ulm, Germany
- German Center for Neurodegenerative Diseases-Ulm (DZNE-Ulm), Ulm, Germany
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Avraham O, Le J, Leahy K, Li T, Zhao G, Cavalli V. Analysis of neuronal injury transcriptional response identifies CTCF and YY1 as co-operating factors regulating axon regeneration. Front Mol Neurosci 2022; 15:967472. [PMID: 36081575 PMCID: PMC9446241 DOI: 10.3389/fnmol.2022.967472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2022] [Accepted: 07/28/2022] [Indexed: 11/13/2022] Open
Abstract
Injured sensory neurons activate a transcriptional program necessary for robust axon regeneration and eventual target reinnervation. Understanding the transcriptional regulators that govern this axon regenerative response may guide therapeutic strategies to promote axon regeneration in the injured nervous system. Here, we used cultured dorsal root ganglia neurons to identify pro-regenerative transcription factors. Using RNA sequencing, we first characterized this neuronal culture and determined that embryonic day 13.5 DRG (eDRG) neurons cultured for 7 days are similar to e15.5 DRG neurons in vivo and that all neuronal subtypes are represented. This eDRG neuronal culture does not contain other non-neuronal cell types. Next, we performed RNA sequencing at different time points after in vitro axotomy. Analysis of differentially expressed genes revealed upregulation of known regeneration associated transcription factors, including Jun, Atf3 and Rest, paralleling the axon injury response in vivo. Analysis of transcription factor binding sites in differentially expressed genes revealed other known transcription factors promoting axon regeneration, such as Myc, Hif1α, Pparγ, Ascl1a, Srf, and Ctcf, as well as other transcription factors not yet characterized in axon regeneration. We next tested if overexpression of novel candidate transcription factors alone or in combination promotes axon regeneration in vitro. Our results demonstrate that expression of Ctcf with Yy1 or E2f2 enhances in vitro axon regeneration. Our analysis highlights that transcription factor interaction and chromatin architecture play important roles as a regulator of axon regeneration.
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Affiliation(s)
- Oshri Avraham
- Department of Neuroscience, Washington University School of Medicine, St. Louis, MO, United States
| | - Jimmy Le
- Department of Neuroscience, Washington University School of Medicine, St. Louis, MO, United States
| | - Kathleen Leahy
- Department of Neuroscience, Washington University School of Medicine, St. Louis, MO, United States
| | - Tiandao Li
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO, United States
- Center of Regenerative Medicine, Washington University School of Medicine, St. Louis, MO, United States
| | - Guoyan Zhao
- Department of Neuroscience, Washington University School of Medicine, St. Louis, MO, United States
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, United States
| | - Valeria Cavalli
- Department of Neuroscience, Washington University School of Medicine, St. Louis, MO, United States
- Center of Regenerative Medicine, Washington University School of Medicine, St. Louis, MO, United States
- Hope Center for Neurological Disorders, Washington University School of Medicine, St. Louis, MO, United States
- *Correspondence: Valeria Cavalli,
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Tabuchi A, Ihara D. SRF in Neurochemistry: Overview of Recent Advances in Research on the Nervous System. Neurochem Res 2022; 47:2545-2557. [PMID: 35668335 DOI: 10.1007/s11064-022-03632-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 04/20/2022] [Accepted: 05/07/2022] [Indexed: 10/18/2022]
Abstract
Serum response factor (SRF) is a representative transcription factor that plays crucial roles in various biological phenomena by regulating immediate early genes (IEGs) and genes related to cell morphology and motility, among others. Over the years, the signal transduction pathways activating SRF have been clarified and SRF-target genes have been identified. In this overview, we initially briefly summarize the basic biology of SRF and its cofactors, ternary complex factor (TCF) and megakaryoblastic leukemia (MKL)/myocardin-related transcription factor (MRTF). Progress in the generation of nervous system-specific knockout (KO) or genetically modified mice as well as genetic analyses over the last few decades has not only identified novel SRF-target genes but also highlighted the neurochemical importance of SRF and its cofactors. Therefore, here we next present the phenotypes of mice with nervous system-specific KO of SRF or its cofactors by depicting recent findings associated with brain development, plasticity, epilepsy, stress response, and drug addiction, all of which result from function or dysfunction of the SRF axis. Last, we develop a hypothesis regarding the possible involvement of SRF and its cofactors in human neurological disorders including neurodegenerative, psychiatric, and neurodevelopmental diseases. This overview should deepen our understanding, highlight promising future directions for developing novel therapeutic strategies, and lead to illumination of the mechanisms underlying higher brain functions based on neuronal structure and function.
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Affiliation(s)
- Akiko Tabuchi
- Laboratory of Molecular Neurobiology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama, 930-0194, Japan.
| | - Daisuke Ihara
- Laboratory of Molecular Neurobiology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama, 930-0194, Japan
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Tabuchi A, Ihara D. Regulation of Dendritic Synaptic Morphology and Transcription by the SRF Cofactor MKL/MRTF. Front Mol Neurosci 2021; 14:767842. [PMID: 34795561 PMCID: PMC8593110 DOI: 10.3389/fnmol.2021.767842] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Accepted: 10/11/2021] [Indexed: 12/12/2022] Open
Abstract
Accumulating evidence suggests that the serum response factor (SRF) cofactor megakaryoblastic leukemia (MKL)/myocardin-related transcription factor (MRTF) has critical roles in many physiological and pathological processes in various cell types. MKL/MRTF molecules comprise MKL1/MRTFA and MKL2/MRTFB, which possess actin-binding motifs at the N-terminus, and SRF-binding domains and a transcriptional activation domain (TAD) at the C-terminus. Several studies have reported that, in association with actin rearrangement, MKL/MRTF translocates from the cytoplasm to the nucleus, where it regulates SRF-mediated gene expression and controls cell motility. Therefore, it is important to elucidate the roles of MKL/MRTF in the nervous system with regard to its structural and functional regulation by extracellular stimuli. We demonstrated that MKL/MRTF is highly expressed in the brain, especially the synapses, and is involved in dendritic complexity and dendritic spine maturation. In addition to the positive regulation of dendritic complexity, we identified several MKL/MRTF isoforms that negatively regulate dendritic complexity in cortical neurons. We found that the MKL/MRTF isoforms were expressed differentially during brain development and the impacts of these isoforms on the immediate early genes including Arc/Arg3.1, were different. Here, we review the roles of MKL/MRTF in the nervous system, with a special focus on the MKL/MRTF-mediated fine-tuning of neuronal morphology and gene transcription. In the concluding remarks, we briefly discuss the future perspectives and the possible involvement of MKL/MRTF in neurological disorders such as schizophrenia and autism spectrum disorder.
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Affiliation(s)
- Akiko Tabuchi
- Laboratory of Molecular Neurobiology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan
| | - Daisuke Ihara
- Laboratory of Molecular Neurobiology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan
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7
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Namme JN, Bepari AK, Takebayashi H. Cofilin Signaling in the CNS Physiology and Neurodegeneration. Int J Mol Sci 2021; 22:ijms221910727. [PMID: 34639067 PMCID: PMC8509315 DOI: 10.3390/ijms221910727] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 09/26/2021] [Accepted: 09/29/2021] [Indexed: 12/18/2022] Open
Abstract
All eukaryotic cells are composed of the cytoskeleton, which plays crucial roles in coordinating diverse cellular functions such as cell division, morphology, migration, macromolecular stabilization, and protein trafficking. The cytoskeleton consists of microtubules, intermediate filaments, and actin filaments. Cofilin, an actin-depolymerizing protein, is indispensable for regulating actin dynamics in the central nervous system (CNS) development and function. Cofilin activities are spatiotemporally orchestrated by numerous extra- and intra-cellular factors. Phosphorylation at Ser-3 by kinases attenuate cofilin’s actin-binding activity. In contrast, dephosphorylation at Ser-3 enhances cofilin-induced actin depolymerization. Cofilin functions are also modulated by various binding partners or reactive oxygen species. Although the mechanism of cofilin-mediated actin dynamics has been known for decades, recent research works are unveiling the profound impacts of cofilin dysregulation in neurodegenerative pathophysiology. For instance, oxidative stress-induced increase in cofilin dephosphorylation is linked to the accumulation of tau tangles and amyloid-beta plaques in Alzheimer’s disease. In Parkinson’s disease, cofilin activation by silencing its upstream kinases increases α-synuclein-fibril entry into the cell. This review describes the molecular mechanism of cofilin-mediated actin dynamics and provides an overview of cofilin’s importance in CNS physiology and pathophysiology.
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Affiliation(s)
- Jannatun Nayem Namme
- Department of Pharmaceutical Sciences, North South University, Dhaka 1229, Bangladesh;
| | - Asim Kumar Bepari
- Department of Pharmaceutical Sciences, North South University, Dhaka 1229, Bangladesh;
- Correspondence: (A.K.B.); (H.T.)
| | - Hirohide Takebayashi
- Division of Neurobiology and Anatomy, Graduate School of Medical and Dental Sciences, Niigata University, Niigata 951-8510, Japan
- Correspondence: (A.K.B.); (H.T.)
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Kiyoshi C, Tedeschi A. Axon growth and synaptic function: A balancing act for axonal regeneration and neuronal circuit formation in CNS trauma and disease. Dev Neurobiol 2020; 80:277-301. [PMID: 32902152 PMCID: PMC7754183 DOI: 10.1002/dneu.22780] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 08/29/2020] [Accepted: 08/31/2020] [Indexed: 12/13/2022]
Abstract
Axons in the adult mammalian central nervous system (CNS) fail to regenerate inside out due to intrinsic and extrinsic neuronal determinants. During CNS development, axon growth, synapse formation, and function are tightly regulated processes allowing immature neurons to effectively grow an axon, navigate toward target areas, form synaptic contacts and become part of information processing networks that control behavior in adulthood. Not only immature neurons are able to precisely control the expression of a plethora of genes necessary for axon extension and pathfinding, synapse formation and function, but also non-neuronal cells such as astrocytes and microglia actively participate in sculpting the nervous system through refinement, consolidation, and elimination of synaptic contacts. Recent evidence indicates that a balancing act between axon regeneration and synaptic function may be crucial for rebuilding functional neuronal circuits after CNS trauma and disease in adulthood. Here, we review the role of classical and new intrinsic and extrinsic neuronal determinants in the context of CNS development, injury, and disease. Moreover, we discuss strategies targeting neuronal and non-neuronal cell behaviors, either alone or in combination, to promote axon regeneration and neuronal circuit formation in adulthood.
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Affiliation(s)
- Conrad Kiyoshi
- Department of Neuroscience, Wexner Medical Center, The Ohio State University, Columbus, OH 43210, USA
| | - Andrea Tedeschi
- Department of Neuroscience, Wexner Medical Center, The Ohio State University, Columbus, OH 43210, USA
- Discovery Theme on Chronic Brain Injury, The Ohio State University, Columbus, OH 43210, USA
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Interference with SRF expression in skeletal muscles reduces peripheral nerve regeneration in mice. Sci Rep 2020; 10:5281. [PMID: 32210317 PMCID: PMC7093445 DOI: 10.1038/s41598-020-62231-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Accepted: 03/09/2020] [Indexed: 11/24/2022] Open
Abstract
Traumatic injury of peripheral nerves typically also damages nerve surrounding tissue including muscles. Hence, molecular and cellular interactions of neighboring damaged tissues might be decisive for successful axonal regeneration of injured nerves. So far, the contribution of muscles and muscle-derived molecules to peripheral nerve regeneration has only poorly been studied. Herein, we conditionally ablated SRF (serum response factor), an important myofiber transcription factor, in skeletal muscles of mice. Subsequently, the impact of this myofiber-restricted SRF deletion on peripheral nerve regeneration, i.e. facial nerve injury was analyzed. Quantification of facial nerve regeneration by retrograde tracer transport, inspection of neuromuscular junctions (NMJs) and recovery of whisker movement revealed reduced axonal regeneration upon muscle specific Srf deletion. In contrast, responses in brainstem facial motor neuron cell bodies such as regeneration-associated gene (RAG) induction of Atf3, synaptic stripping and neuroinflammation were not overly affected by SRF deficiency. Mechanistically, SRF in myofibers appears to stimulate nerve regeneration through regulation of muscular satellite cell (SC) proliferation. In summary, our data suggest a role of muscle cells and SRF expression within muscles for regeneration of injured peripheral nerves.
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Filomena MC, Yamamoto DL, Caremani M, Kadarla VK, Mastrototaro G, Serio S, Vydyanath A, Mutarelli M, Garofalo A, Pertici I, Knöll R, Nigro V, Luther PK, Lieber RL, Beck MR, Linari M, Bang M. Myopalladin promotes muscle growth through modulation of the serum response factor pathway. J Cachexia Sarcopenia Muscle 2020; 11:169-194. [PMID: 31647200 PMCID: PMC7015241 DOI: 10.1002/jcsm.12486] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Revised: 07/01/2019] [Accepted: 07/22/2019] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Myopalladin (MYPN) is a striated muscle-specific, immunoglobulin-containing protein located in the Z-line and I-band of the sarcomere as well as the nucleus. Heterozygous MYPN gene mutations are associated with hypertrophic, dilated, and restrictive cardiomyopathy, and homozygous loss-of-function truncating mutations have recently been identified in patients with cap myopathy, nemaline myopathy, and congenital myopathy with hanging big toe. METHODS Constitutive MYPN knockout (MKO) mice were generated, and the role of MYPN in skeletal muscle was studied through molecular, cellular, biochemical, structural, biomechanical, and physiological studies in vivo and in vitro. RESULTS MKO mice were 13% smaller compared with wild-type controls and exhibited a 48% reduction in myofibre cross-sectional area (CSA) and significantly increased fibre number. Similarly, reduced myotube width was observed in MKO primary myoblast cultures. Biomechanical studies showed reduced isometric force and power output in MKO mice as a result of the reduced CSA, whereas the force developed by each myosin molecular motor was unaffected. While the performance by treadmill running was similar in MKO and wild-type mice, MKO mice showed progressively decreased exercise capability, Z-line damage, and signs of muscle regeneration following consecutive days of downhill running. Additionally, MKO muscle exhibited progressive Z-line widening starting from 8 months of age. RNA-sequencing analysis revealed down-regulation of serum response factor (SRF)-target genes in muscles from postnatal MKO mice, important for muscle growth and differentiation. The SRF pathway is regulated by actin dynamics as binding of globular actin to the SRF-cofactor myocardin-related transcription factor A (MRTF-A) prevents its translocation to the nucleus where it binds and activates SRF. MYPN was found to bind and bundle filamentous actin as well as interact with MRTF-A. In particular, while MYPN reduced actin polymerization, it strongly inhibited actin depolymerization and consequently increased MRTF-A-mediated activation of SRF signalling in myogenic cells. Reduced myotube width in MKO primary myoblast cultures was rescued by transduction with constitutive active SRF, demonstrating that MYPN promotes skeletal muscle growth through activation of the SRF pathway. CONCLUSIONS Myopalladin plays a critical role in the control of skeletal muscle growth through its effect on actin dynamics and consequently the SRF pathway. In addition, MYPN is important for the maintenance of Z-line integrity during exercise and aging. These results suggest that muscle weakness in patients with biallelic MYPN mutations may be associated with reduced myofibre CSA and SRF signalling and that the disease phenotype may be aggravated by exercise.
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Affiliation(s)
- Maria Carmela Filomena
- Institute of Genetic and Biomedical Research (IRGB), Milan UnitNational Research CouncilMilanItaly
- Humanitas Clinical and Research CenterRozzanoMilanItaly
| | - Daniel L. Yamamoto
- Institute of Genetic and Biomedical Research (IRGB), Milan UnitNational Research CouncilMilanItaly
| | - Marco Caremani
- Department of BiologyUniversity of FlorenceSesto FiorentinoFlorenceItaly
| | | | | | - Simone Serio
- Humanitas Clinical and Research CenterRozzanoMilanItaly
| | | | | | - Arcamaria Garofalo
- Telethon Institute of Genetics and Medicine (TIGEM)PozzuoliItaly
- Department of Precision MedicineUniversity of Campania “Luigi Vanvitelli”NaplesItaly
| | - Irene Pertici
- Department of BiologyUniversity of FlorenceSesto FiorentinoFlorenceItaly
| | - Ralph Knöll
- Integrated Cardio Metabolic Centre (ICMC), Myocardial GeneticsKarolinska Institutet, University Hospital, Heart and Vascular ThemeSweden
- Research and Early Development, Cardiovascular, Renal and Metabolic Diseases (CVRM), Biopharmaceuticals R&DAstraZenecaMölndalSweden
| | - Vincenzo Nigro
- Telethon Institute of Genetics and Medicine (TIGEM)PozzuoliItaly
- Department of Precision MedicineUniversity of Campania “Luigi Vanvitelli”NaplesItaly
| | | | - Richard L. Lieber
- Shirley Ryan AbilityLab and Hines V.A. Medical Center ChicagoChicagoILUSA
- Department of Physical Medicine and RehabilitationNorthwestern UniversityChicagoILUSA
- Department of Orthopaedic SurgeryUniversity of California San DiegoLa JollaCAUSA
| | - Moriah R. Beck
- Department of ChemistryWichita State UniversityWichitaKSUSA
| | - Marco Linari
- Department of BiologyUniversity of FlorenceSesto FiorentinoFlorenceItaly
| | - Marie‐Louise Bang
- Institute of Genetic and Biomedical Research (IRGB), Milan UnitNational Research CouncilMilanItaly
- Humanitas Clinical and Research CenterRozzanoMilanItaly
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11
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Förstner P, Knöll B. Interference of neuronal activity-mediated gene expression through serum response factor deletion enhances mortality and hyperactivity after traumatic brain injury. FASEB J 2020; 34:3855-3873. [PMID: 31930559 DOI: 10.1096/fj.201902257rr] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Revised: 12/19/2019] [Accepted: 12/23/2019] [Indexed: 12/31/2022]
Abstract
Traumatic brain injury (TBI) is one of the most frequent causes of brain injury and mortality in young adults with detrimental sequelae such as cognitive impairments, epilepsy, and attention-deficit hyperactivity disorder. TBI modulates the neuronal excitability resulting in propagation of a neuronal activity-driven gene expression program. However, the impact of such neuronal activity mediated gene expression in TBI has been poorly studied. In this study we analyzed mouse mutants of the prototypical neuronal activity-dependent transcription factor SRF (serum response factor) in a weight-drop TBI model. Neuron-restricted SRF deletion elevated TBI inflicted mortality suggesting a neuroprotective SRF function during TBI. Behavioral inspection uncovered elevated locomotor activity in Srf mutant mice after TBI in contrast to hypoactivity observed in wild-type littermates. This indicates an SRF role in modulation of TBI-associated alterations in locomotor activity. Finally, induction of a neuronal activity induced gene expression program composed of immediate early genes (IEGs) such as Egr1, Egr2, Egr3, Npas4, Atf3, Arc, Ptgs2, and neuronal pentraxins (Nptx2) was compromised upon SRF depletion. Overall, our data show a role of neuronal activity-mediated gene transcription during TBI and suggest a molecular link between TBI and such post-TBI neurological comorbidities involving hyperactivity phenotypes.
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Affiliation(s)
- Philip Förstner
- Institute of Physiological Chemistry, Ulm University, Ulm, Germany
| | - Bernd Knöll
- Institute of Physiological Chemistry, Ulm University, Ulm, Germany
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Ni HY, Song YX, Lin YH, Cao B, Wang DL, Zhang Y, Dong J, Liang HY, Xu K, Li TY, Chang L, Wu HY, Luo CX, Zhu DY. Dissociating nNOS (Neuronal NO Synthase)-CAPON (Carboxy-Terminal Postsynaptic Density-95/Discs Large/Zona Occludens-1 Ligand of nNOS) Interaction Promotes Functional Recovery After Stroke via Enhanced Structural Neuroplasticity. Stroke 2019; 50:728-737. [PMID: 30727847 DOI: 10.1161/strokeaha.118.022647] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Background and Purpose- Stroke is a major public health concern worldwide. Although clinical treatments have improved in the acute period after stroke, long-term therapeutics remain limited to physical rehabilitation in the delayed phase. This study is aimed to determine whether nNOS (neuronal NO synthase)-CAPON (carboxy-terminal postsynaptic density-95/discs large/zona occludens-1 ligand of nNOS) interaction may serve as a new therapeutic target in the delayed phase for stroke recovery. Methods- Photothrombotic stroke and transient middle cerebral artery occlusion were induced in mice. Adeno-associated virus (AAV)-cytomegalovirus (CMV)-CAPON-125C-GFP (green fluorescent protein)-3Flag and the other 2 drugs (Tat-CAPON-12C and ZLc-002) were microinjected into the peri-infarct cortex immediately and 4 to 10 days after photothrombotic stroke, respectively. ZLc-002 was also systemically injected 4 to 10 days after transient middle cerebral artery occlusion. Grid-walking task and cylinder task were conducted to assess motor function. Western blotting, immunohistochemistry, Golgi staining, and electrophysiology recordings were performed to uncover the mechanisms. Results- Stroke increased nNOS-CAPON association in the peri-infarct cortex in the delayed period. Inhibiting the ischemia-induced nNOS-CAPON association substantially decreased the number of foot faults in the grid-walking task and forelimb asymmetry in the cylinder task, suggesting the promotion of functional recovery from stroke. Moreover, dissociating nNOS-CAPON significantly facilitated dendritic remodeling and synaptic transmission, indicated by increased dendritic spine density, dendritic branching, and length and miniature excitatory postsynaptic current frequency but did not affect stroke-elicited neuronal loss, infarct size, or cerebral edema, suggesting that nNOS-CAPON interaction may function via regulating structural neuroplasticity, rather than neuroprotection. Furthermore, ZLc-002 reversed the transient middle cerebral artery occlusion-induced impairment of motor function. Conclusions- Our results reveal that nNOS-CAPON coupling can serve as a novel pharmacological target for functional restoration after stroke.
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Affiliation(s)
- Huan-Yu Ni
- From the Institution of Stem Cells and Neuroregeneration (H.-Y.N., Y.-X.S., Y.-H.L., B.C., D.-L.W., Y.Z., J.D., H.-Y.L., K.X., T.-Y.L., L.C., H.-Y.W., C.-X.L., D.-Y.Z.), Nanjing Medical University, China.,Department of Pharmacology, School of Pharmacy (H.-Y.N., Y.-X.S., Y.-H.L., B.C., D.-L.W., Y.Z., J.D., H.-Y.L., K.X., T.-Y.L., L.C., H.-Y.W., C.-X.L., D.-Y.Z.), Nanjing Medical University, China
| | - Yi-Xuan Song
- From the Institution of Stem Cells and Neuroregeneration (H.-Y.N., Y.-X.S., Y.-H.L., B.C., D.-L.W., Y.Z., J.D., H.-Y.L., K.X., T.-Y.L., L.C., H.-Y.W., C.-X.L., D.-Y.Z.), Nanjing Medical University, China.,Department of Pharmacology, School of Pharmacy (H.-Y.N., Y.-X.S., Y.-H.L., B.C., D.-L.W., Y.Z., J.D., H.-Y.L., K.X., T.-Y.L., L.C., H.-Y.W., C.-X.L., D.-Y.Z.), Nanjing Medical University, China
| | - Yu-Hui Lin
- From the Institution of Stem Cells and Neuroregeneration (H.-Y.N., Y.-X.S., Y.-H.L., B.C., D.-L.W., Y.Z., J.D., H.-Y.L., K.X., T.-Y.L., L.C., H.-Y.W., C.-X.L., D.-Y.Z.), Nanjing Medical University, China.,Department of Pharmacology, School of Pharmacy (H.-Y.N., Y.-X.S., Y.-H.L., B.C., D.-L.W., Y.Z., J.D., H.-Y.L., K.X., T.-Y.L., L.C., H.-Y.W., C.-X.L., D.-Y.Z.), Nanjing Medical University, China
| | - Bo Cao
- From the Institution of Stem Cells and Neuroregeneration (H.-Y.N., Y.-X.S., Y.-H.L., B.C., D.-L.W., Y.Z., J.D., H.-Y.L., K.X., T.-Y.L., L.C., H.-Y.W., C.-X.L., D.-Y.Z.), Nanjing Medical University, China.,Department of Pharmacology, School of Pharmacy (H.-Y.N., Y.-X.S., Y.-H.L., B.C., D.-L.W., Y.Z., J.D., H.-Y.L., K.X., T.-Y.L., L.C., H.-Y.W., C.-X.L., D.-Y.Z.), Nanjing Medical University, China
| | - Dong-Liang Wang
- From the Institution of Stem Cells and Neuroregeneration (H.-Y.N., Y.-X.S., Y.-H.L., B.C., D.-L.W., Y.Z., J.D., H.-Y.L., K.X., T.-Y.L., L.C., H.-Y.W., C.-X.L., D.-Y.Z.), Nanjing Medical University, China.,Department of Pharmacology, School of Pharmacy (H.-Y.N., Y.-X.S., Y.-H.L., B.C., D.-L.W., Y.Z., J.D., H.-Y.L., K.X., T.-Y.L., L.C., H.-Y.W., C.-X.L., D.-Y.Z.), Nanjing Medical University, China
| | - Yu Zhang
- From the Institution of Stem Cells and Neuroregeneration (H.-Y.N., Y.-X.S., Y.-H.L., B.C., D.-L.W., Y.Z., J.D., H.-Y.L., K.X., T.-Y.L., L.C., H.-Y.W., C.-X.L., D.-Y.Z.), Nanjing Medical University, China.,Department of Pharmacology, School of Pharmacy (H.-Y.N., Y.-X.S., Y.-H.L., B.C., D.-L.W., Y.Z., J.D., H.-Y.L., K.X., T.-Y.L., L.C., H.-Y.W., C.-X.L., D.-Y.Z.), Nanjing Medical University, China
| | - Jian Dong
- From the Institution of Stem Cells and Neuroregeneration (H.-Y.N., Y.-X.S., Y.-H.L., B.C., D.-L.W., Y.Z., J.D., H.-Y.L., K.X., T.-Y.L., L.C., H.-Y.W., C.-X.L., D.-Y.Z.), Nanjing Medical University, China.,Department of Pharmacology, School of Pharmacy (H.-Y.N., Y.-X.S., Y.-H.L., B.C., D.-L.W., Y.Z., J.D., H.-Y.L., K.X., T.-Y.L., L.C., H.-Y.W., C.-X.L., D.-Y.Z.), Nanjing Medical University, China
| | - Hai-Ying Liang
- From the Institution of Stem Cells and Neuroregeneration (H.-Y.N., Y.-X.S., Y.-H.L., B.C., D.-L.W., Y.Z., J.D., H.-Y.L., K.X., T.-Y.L., L.C., H.-Y.W., C.-X.L., D.-Y.Z.), Nanjing Medical University, China.,Department of Pharmacology, School of Pharmacy (H.-Y.N., Y.-X.S., Y.-H.L., B.C., D.-L.W., Y.Z., J.D., H.-Y.L., K.X., T.-Y.L., L.C., H.-Y.W., C.-X.L., D.-Y.Z.), Nanjing Medical University, China
| | - Ke Xu
- From the Institution of Stem Cells and Neuroregeneration (H.-Y.N., Y.-X.S., Y.-H.L., B.C., D.-L.W., Y.Z., J.D., H.-Y.L., K.X., T.-Y.L., L.C., H.-Y.W., C.-X.L., D.-Y.Z.), Nanjing Medical University, China.,Department of Pharmacology, School of Pharmacy (H.-Y.N., Y.-X.S., Y.-H.L., B.C., D.-L.W., Y.Z., J.D., H.-Y.L., K.X., T.-Y.L., L.C., H.-Y.W., C.-X.L., D.-Y.Z.), Nanjing Medical University, China
| | - Ting-You Li
- From the Institution of Stem Cells and Neuroregeneration (H.-Y.N., Y.-X.S., Y.-H.L., B.C., D.-L.W., Y.Z., J.D., H.-Y.L., K.X., T.-Y.L., L.C., H.-Y.W., C.-X.L., D.-Y.Z.), Nanjing Medical University, China.,Department of Pharmacology, School of Pharmacy (H.-Y.N., Y.-X.S., Y.-H.L., B.C., D.-L.W., Y.Z., J.D., H.-Y.L., K.X., T.-Y.L., L.C., H.-Y.W., C.-X.L., D.-Y.Z.), Nanjing Medical University, China.,Department of Medicinal Chemistry, School of Pharmacy (T.-Y.L.), Nanjing Medical University, China.,Collaborative Innovation Center for Cardiovascular Disease Translational Medicine, Nanjing, China (T.-Y.L., C.-X.L., D.-Y.Z.)
| | - Lei Chang
- From the Institution of Stem Cells and Neuroregeneration (H.-Y.N., Y.-X.S., Y.-H.L., B.C., D.-L.W., Y.Z., J.D., H.-Y.L., K.X., T.-Y.L., L.C., H.-Y.W., C.-X.L., D.-Y.Z.), Nanjing Medical University, China.,Department of Pharmacology, School of Pharmacy (H.-Y.N., Y.-X.S., Y.-H.L., B.C., D.-L.W., Y.Z., J.D., H.-Y.L., K.X., T.-Y.L., L.C., H.-Y.W., C.-X.L., D.-Y.Z.), Nanjing Medical University, China
| | - Hai-Yin Wu
- From the Institution of Stem Cells and Neuroregeneration (H.-Y.N., Y.-X.S., Y.-H.L., B.C., D.-L.W., Y.Z., J.D., H.-Y.L., K.X., T.-Y.L., L.C., H.-Y.W., C.-X.L., D.-Y.Z.), Nanjing Medical University, China.,Department of Pharmacology, School of Pharmacy (H.-Y.N., Y.-X.S., Y.-H.L., B.C., D.-L.W., Y.Z., J.D., H.-Y.L., K.X., T.-Y.L., L.C., H.-Y.W., C.-X.L., D.-Y.Z.), Nanjing Medical University, China
| | - Chun-Xia Luo
- From the Institution of Stem Cells and Neuroregeneration (H.-Y.N., Y.-X.S., Y.-H.L., B.C., D.-L.W., Y.Z., J.D., H.-Y.L., K.X., T.-Y.L., L.C., H.-Y.W., C.-X.L., D.-Y.Z.), Nanjing Medical University, China.,Department of Pharmacology, School of Pharmacy (H.-Y.N., Y.-X.S., Y.-H.L., B.C., D.-L.W., Y.Z., J.D., H.-Y.L., K.X., T.-Y.L., L.C., H.-Y.W., C.-X.L., D.-Y.Z.), Nanjing Medical University, China.,Collaborative Innovation Center for Cardiovascular Disease Translational Medicine, Nanjing, China (T.-Y.L., C.-X.L., D.-Y.Z.)
| | - Dong-Ya Zhu
- From the Institution of Stem Cells and Neuroregeneration (H.-Y.N., Y.-X.S., Y.-H.L., B.C., D.-L.W., Y.Z., J.D., H.-Y.L., K.X., T.-Y.L., L.C., H.-Y.W., C.-X.L., D.-Y.Z.), Nanjing Medical University, China.,Department of Pharmacology, School of Pharmacy (H.-Y.N., Y.-X.S., Y.-H.L., B.C., D.-L.W., Y.Z., J.D., H.-Y.L., K.X., T.-Y.L., L.C., H.-Y.W., C.-X.L., D.-Y.Z.), Nanjing Medical University, China.,Collaborative Innovation Center for Cardiovascular Disease Translational Medicine, Nanjing, China (T.-Y.L., C.-X.L., D.-Y.Z.)
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Abstract
Permanent disabilities following CNS injuries result from the failure of injured axons to regenerate and rebuild functional connections with their original targets. By contrast, injury to peripheral nerves is followed by robust regeneration, which can lead to recovery of sensory and motor functions. This regenerative response requires the induction of widespread transcriptional and epigenetic changes in injured neurons. Considerable progress has been made in recent years in understanding how peripheral axon injury elicits these widespread changes through the coordinated actions of transcription factors, epigenetic modifiers and, to a lesser extent, microRNAs. Although many questions remain about the interplay between these mechanisms, these new findings provide important insights into the pivotal role of coordinated gene expression and chromatin remodelling in the neuronal response to injury.
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Affiliation(s)
- Marcus Mahar
- Department of Neuroscience, Hope Center for Neurological Disorders and Center of Regenerative Medicine, Washington University School of Medicine, St Louis, MO, USA
| | - Valeria Cavalli
- Department of Neuroscience, Hope Center for Neurological Disorders and Center of Regenerative Medicine, Washington University School of Medicine, St Louis, MO, USA.
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14
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Abstract
Traumatic brain and spinal cord injuries cause permanent disability. Although progress has been made in understanding the cellular and molecular mechanisms underlying the pathophysiological changes that affect both structure and function after injury to the brain or spinal cord, there are currently no cures for either condition. This may change with the development and application of multi-layer omics, new sophisticated bioinformatics tools, and cutting-edge imaging techniques. Already, these technical advances, when combined, are revealing an unprecedented number of novel cellular and molecular targets that could be manipulated alone or in combination to repair the injured central nervous system with precision. In this review, we highlight recent advances in applying these new technologies to the study of axon regeneration and rebuilding of injured neural circuitry. We then discuss the challenges ahead to translate results produced by these technologies into clinical application to help improve the lives of individuals who have a brain or spinal cord injury.
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Affiliation(s)
- Andrea Tedeschi
- Department of Neuroscience and Discovery Themes Initiative, College of Medicine, Ohio State University, Columbus, Ohio, 43210, USA
| | - Phillip G Popovich
- Center for Brain and Spinal Cord Repair, Institute for Behavioral Medicine Research, Ohio State University, Columbus, Ohio, 43210, USA
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15
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Gey M, Wanner R, Schilling C, Pedro MT, Sinske D, Knöll B. Atf3 mutant mice show reduced axon regeneration and impaired regeneration-associated gene induction after peripheral nerve injury. Open Biol 2017; 6:rsob.160091. [PMID: 27581653 PMCID: PMC5008009 DOI: 10.1098/rsob.160091] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Accepted: 08/01/2016] [Indexed: 12/27/2022] Open
Abstract
Axon injury in the peripheral nervous system (PNS) induces a regeneration-associated gene (RAG) response. Atf3 (activating transcription factor 3) is such a RAG and ATF3's transcriptional activity might induce ‘effector’ RAGs (e.g. small proline rich protein 1a (Sprr1a), Galanin (Gal), growth-associated protein 43 (Gap43)) facilitating peripheral axon regeneration. We provide a first analysis of Atf3 mouse mutants in peripheral nerve regeneration. In Atf3 mutant mice, facial nerve regeneration and neurite outgrowth of adult ATF3-deficient primary dorsal root ganglia neurons was decreased. Using genome-wide transcriptomics, we identified a neuropeptide-encoding RAG cluster (vasoactive intestinal peptide (Vip), Ngf, Grp, Gal, Pacap) regulated by ATF3. Exogenous administration of neuropeptides enhanced neurite growth of Atf3 mutant mice suggesting that these molecules might be effector RAGs of ATF3's pro-regenerative function. In addition to the induction of growth-promoting molecules, we present data that ATF3 suppresses growth-inhibiting molecules such as chemokine (C-C motif) ligand 2. In summary, we show a pro-regenerative ATF3 function during PNS nerve regeneration involving transcriptional activation of a neuropeptide-encoding RAG cluster. ATF3 is a general injury-inducible factor, therefore ATF3-mediated mechanisms identified herein might apply to other cell and injury types.
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Affiliation(s)
- Manuel Gey
- Institute of Physiological Chemistry, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany
| | - Renate Wanner
- Institute of Physiological Chemistry, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany
| | - Corinna Schilling
- Institute of Physiological Chemistry, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany
| | - Maria T Pedro
- Department of Neurosurgery, Bezirkskrankenhaus Günzburg, Ulm University, 89081 Ulm, Germany
| | - Daniela Sinske
- Institute of Physiological Chemistry, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany
| | - Bernd Knöll
- Institute of Physiological Chemistry, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany
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16
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Djordjevic D, Kusumi K, Ho JWK. XGSA: A statistical method for cross-species gene set analysis. Bioinformatics 2017; 32:i620-i628. [PMID: 27587682 DOI: 10.1093/bioinformatics/btw428] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
MOTIVATION Gene set analysis is a powerful tool for determining whether an experimentally derived set of genes is statistically significantly enriched for genes in other pre-defined gene sets, such as known pathways, gene ontology terms, or other experimentally derived gene sets. Current gene set analysis methods do not facilitate comparing gene sets across different organisms as they do not explicitly deal with homology mapping between species. There lacks a systematic investigation about the effect of complex gene homology on cross-species gene set analysis. RESULTS In this study, we show that not accounting for the complex homology structure when comparing gene sets in two species can lead to false positive discoveries, especially when comparing gene sets that have complex gene homology relationships. To overcome this bias, we propose a straightforward statistical approach, called XGSA, that explicitly takes the cross-species homology mapping into consideration when doing gene set analysis. Simulation experiments confirm that XGSA can avoid false positive discoveries, while maintaining good statistical power compared to other ad hoc approaches for cross-species gene set analysis. We further demonstrate the effectiveness of XGSA with two real-life case studies that aim to discover conserved or species-specific molecular pathways involved in social challenge and vertebrate appendage regeneration. AVAILABILITY AND IMPLEMENTATION The R source code for XGSA is available under a GNU General Public License at http://github.com/VCCRI/XGSA CONTACT: jho@victorchang.edu.au.
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Affiliation(s)
- Djordje Djordjevic
- Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia, St Vincent's Clinical School, University of New South Wales Australia, Darlinghurst, NSW 2010, Australia
| | - Kenro Kusumi
- School of Life Sciences, Arizona State University, Tempe, AZ 85287, USA
| | - Joshua W K Ho
- Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia, St Vincent's Clinical School, University of New South Wales Australia, Darlinghurst, NSW 2010, Australia
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17
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Lösing P, Niturad CE, Harrer M, Reckendorf CMZ, Schatz T, Sinske D, Lerche H, Maljevic S, Knöll B. SRF modulates seizure occurrence, activity induced gene transcription and hippocampal circuit reorganization in the mouse pilocarpine epilepsy model. Mol Brain 2017; 10:30. [PMID: 28716058 PMCID: PMC5513048 DOI: 10.1186/s13041-017-0310-2] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Accepted: 06/28/2017] [Indexed: 11/10/2022] Open
Abstract
A hallmark of temporal lobe epilepsy (TLE) is hippocampal neuronal demise and aberrant mossy fiber sprouting. In addition, unrestrained neuronal activity in TLE patients induces gene expression including immediate early genes (IEGs) such as Fos and Egr1. We employed the mouse pilocarpine model to analyze the transcription factor (TF) serum response factor (SRF) in epileptogenesis, seizure induced histopathology and IEG induction. SRF is a neuronal activity regulated TF stimulating IEG expression as well as nerve fiber growth and guidance. Adult conditional SRF deficient mice (SrfCaMKCreERT2) were more refractory to initial status epilepticus (SE) acquisition. Further, SRF deficient mice developed more spontaneous recurrent seizures (SRS). Genome-wide transcriptomic analysis uncovered a requirement of SRF for SE and SRS induced IEG induction (e.g. Fos, Egr1, Arc, Npas4, Btg2, Atf3). SRF was required for epilepsy associated neurodegeneration, mossy fiber sprouting and inflammation. We uncovered MAP kinase signaling as SRF target during epilepsy. Upon SRF ablation, seizure evoked induction of dual specific phosphatases (Dusp5 and Dusp6) was reduced. Lower expression of these negative ERK kinase regulators correlated with altered P-ERK levels in epileptic Srf mutant animals. Overall, this study uncovered an SRF contribution to several processes of epileptogenesis in the pilocarpine model.
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Affiliation(s)
- Pascal Lösing
- Institute of Physiological Chemistry, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Cristina Elena Niturad
- Department of Neurology and Epileptology, Hertie-Institute of Clinical Brain Research, University of Tübingen, Hoppe-Seyler-Straße 3, 72076, Tübingen, Germany
| | - Merle Harrer
- Department of Neurology and Epileptology, Hertie-Institute of Clinical Brain Research, University of Tübingen, Hoppe-Seyler-Straße 3, 72076, Tübingen, Germany
| | | | - Theresa Schatz
- Institute of Physiological Chemistry, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Daniela Sinske
- Institute of Physiological Chemistry, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Holger Lerche
- Department of Neurology and Epileptology, Hertie-Institute of Clinical Brain Research, University of Tübingen, Hoppe-Seyler-Straße 3, 72076, Tübingen, Germany
| | - Snezana Maljevic
- Department of Neurology and Epileptology, Hertie-Institute of Clinical Brain Research, University of Tübingen, Hoppe-Seyler-Straße 3, 72076, Tübingen, Germany.,Present address: The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville VIC, Melbourne, 3052, Australia
| | - Bernd Knöll
- Institute of Physiological Chemistry, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany.
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18
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Functional and Molecular Characterization of a Novel Traumatic Peripheral Nerve–Muscle Injury Model. Neuromolecular Med 2017; 19:357-374. [DOI: 10.1007/s12017-017-8450-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Accepted: 07/01/2017] [Indexed: 10/19/2022]
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19
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Motti D, Lerch JK, Danzi MC, Gans JH, Kuo F, Slepak TI, Bixby JL, Lemmon VP. Identification of miRNAs involved in DRG neurite outgrowth and their putative targets. FEBS Lett 2017; 591:2091-2105. [PMID: 28626869 PMCID: PMC5864114 DOI: 10.1002/1873-3468.12718] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Revised: 06/07/2017] [Accepted: 06/11/2017] [Indexed: 12/14/2022]
Abstract
Peripheral neurons regenerate their axons after injury. Transcriptional regulation by microRNAs (miRNAs) is one possible mechanism controlling regeneration. We profiled miRNA expression in mouse dorsal root ganglion neurons after a sciatic nerve crush, and identified 49 differentially expressed miRNAs. We evaluated the functional role of each miRNA using a phenotypic analysis approach. To predict the targets of the miRNAs we employed RNA-Sequencing and examined transcription at the isoform level. We identify thousands of differentially expressed isoforms and bioinformatically associate the miRNAs that modulate neurite growth with their putative target isoforms to outline a network of regulatory events underlying peripheral nerve regeneration. MiR-298, let-7a, and let-7f enhance neurite growth and target the majority of isoforms in the differentially expressed network.
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Affiliation(s)
- Dario Motti
- The Miami Project To Cure Paralysis, The University of Miami Miller School of Medicine, Miami, FL
| | - Jessica K. Lerch
- The Department of Neuroscience, The Ohio State University, Columbus, OH
| | - Matt C. Danzi
- The Miami Project To Cure Paralysis, The University of Miami Miller School of Medicine, Miami, FL
| | - Jared H. Gans
- The Miami Project To Cure Paralysis, The University of Miami Miller School of Medicine, Miami, FL
| | - Frank Kuo
- The Miami Project To Cure Paralysis, The University of Miami Miller School of Medicine, Miami, FL
| | - Tatiana I. Slepak
- The Miami Project To Cure Paralysis, The University of Miami Miller School of Medicine, Miami, FL
| | - John L. Bixby
- The Miami Project To Cure Paralysis, The University of Miami Miller School of Medicine, Miami, FL
- The Department of Molecular and Cellular Pharmacology, The University of Miami Miller School of Medicine, Miami, FL
- The Department of Neurological Surgery, The University of Miami Miller School of Medicine, Miami, FL
- The Center for Computational Science, The University of Miami, Miami, FL
| | - Vance P. Lemmon
- The Miami Project To Cure Paralysis, The University of Miami Miller School of Medicine, Miami, FL
- The Department of Neurological Surgery, The University of Miami Miller School of Medicine, Miami, FL
- The Center for Computational Science, The University of Miami, Miami, FL
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20
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Ryba DM, Li J, Cowan CL, Russell B, Wolska BM, Solaro RJ. Long-Term Biased β-Arrestin Signaling Improves Cardiac Structure and Function in Dilated Cardiomyopathy. Circulation 2017; 135:1056-1070. [PMID: 28104714 DOI: 10.1161/circulationaha.116.024482] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Accepted: 01/12/2017] [Indexed: 12/20/2022]
Abstract
BACKGROUND Biased agonism of the angiotensin II receptor is known to promote cardiac contractility. Our laboratory indicated that these effects may be attributable to changes at the level of the myofilaments. However, these signaling mechanisms remain unknown. Because a common finding in dilated cardiomyopathy is a reduction in the myofilament-Ca2+ response, we hypothesized that β-arrestin signaling would increase myofilament-Ca2+ responsiveness in a model of familial dilated cardiomyopathy and improve cardiac function and morphology. METHODS We treated a dilated cardiomyopathy-linked mouse model expressing a mutant tropomyosin (Tm-E54K) for 3 months with either TRV120067, a β-arrestin 2-biased ligand of the angiotensin II receptor, or losartan, an angiotensin II receptor blocker. At the end of the treatment protocol, we assessed cardiac function using echocardiography, the myofilament-Ca2+ response of detergent-extracted fiber bundles, and used proteomic approaches to understand changes in posttranslational modifications of proteins that may explain functional changes. We also assessed signaling pathways altered in vivo and by using isolated myocytes. RESULTS TRV120067- treated Tm-E54K mice showed improved cardiac structure and function, whereas losartan-treated mice had no improvement. Myofilaments of TRV120067-treated Tm-E54K mice had significantly improved myofilament-Ca2+ responsiveness, which was depressed in untreated Tm-E54K mice. We attributed these changes to increased MLC2v and MYPT1/2 phosphorylation seen only in TRV120067-treated mice. We found that the functional changes were attributable to an activation of ERK1/2-RSK3 signaling, mediated through β-arrestin, which may have a novel role in increasing MLC2v phosphorylation through a previously unrecognized interaction of β-arrestin localized to the sarcomere. CONCLUSIONS Long-term β-arrestin 2-biased agonism of the angiotensin II receptor may be a viable approach to the treatment of dilated cardiomyopathy by not only preventing maladaptive signaling, but also improving cardiac function by altering the myofilament-Ca2+ response via β-arrestin signaling pathways.
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Affiliation(s)
- David M Ryba
- From Department of Physiology and Biophysics and Center for Cardiovascular Research, University of Illinois at Chicago (D.M.R., J.L., B.R., B.M.W., R.J.S.); Department of Medicine, Division of Cardiology, University of Illinois at Chicago (B.M.W.); and Trevena, Inc. King of Prussia, PA (B.M.W.)
| | - Jieli Li
- From Department of Physiology and Biophysics and Center for Cardiovascular Research, University of Illinois at Chicago (D.M.R., J.L., B.R., B.M.W., R.J.S.); Department of Medicine, Division of Cardiology, University of Illinois at Chicago (B.M.W.); and Trevena, Inc. King of Prussia, PA (B.M.W.)
| | - Conrad L Cowan
- From Department of Physiology and Biophysics and Center for Cardiovascular Research, University of Illinois at Chicago (D.M.R., J.L., B.R., B.M.W., R.J.S.); Department of Medicine, Division of Cardiology, University of Illinois at Chicago (B.M.W.); and Trevena, Inc. King of Prussia, PA (B.M.W.)
| | - Brenda Russell
- From Department of Physiology and Biophysics and Center for Cardiovascular Research, University of Illinois at Chicago (D.M.R., J.L., B.R., B.M.W., R.J.S.); Department of Medicine, Division of Cardiology, University of Illinois at Chicago (B.M.W.); and Trevena, Inc. King of Prussia, PA (B.M.W.)
| | - Beata M Wolska
- From Department of Physiology and Biophysics and Center for Cardiovascular Research, University of Illinois at Chicago (D.M.R., J.L., B.R., B.M.W., R.J.S.); Department of Medicine, Division of Cardiology, University of Illinois at Chicago (B.M.W.); and Trevena, Inc. King of Prussia, PA (B.M.W.)
| | - R John Solaro
- From Department of Physiology and Biophysics and Center for Cardiovascular Research, University of Illinois at Chicago (D.M.R., J.L., B.R., B.M.W., R.J.S.); Department of Medicine, Division of Cardiology, University of Illinois at Chicago (B.M.W.); and Trevena, Inc. King of Prussia, PA (B.M.W.).
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21
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Sivadasan R, Hornburg D, Drepper C, Frank N, Jablonka S, Hansel A, Lojewski X, Sterneckert J, Hermann A, Shaw PJ, Ince PG, Mann M, Meissner F, Sendtner M. C9ORF72 interaction with cofilin modulates actin dynamics in motor neurons. Nat Neurosci 2016; 19:1610-1618. [PMID: 27723745 DOI: 10.1038/nn.4407] [Citation(s) in RCA: 118] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Accepted: 09/08/2016] [Indexed: 12/14/2022]
Abstract
Intronic hexanucleotide expansions in C9ORF72 are common in amyotrophic lateral sclerosis (ALS) and frontotemporal dementia, but it is unknown whether loss of function, toxicity by the expanded RNA or dipeptides from non-ATG-initiated translation are responsible for the pathophysiology. We determined the interactome of C9ORF72 in motor neurons and found that C9ORF72 was present in a complex with cofilin and other actin binding proteins. Phosphorylation of cofilin was enhanced in C9ORF72-depleted motor neurons, in patient-derived lymphoblastoid cells, induced pluripotent stem cell-derived motor neurons and post-mortem brain samples from ALS patients. C9ORF72 modulates the activity of the small GTPases Arf6 and Rac1, resulting in enhanced activity of LIM-kinases 1 and 2 (LIMK1/2). This results in reduced axonal actin dynamics in C9ORF72-depleted motor neurons. Dominant negative Arf6 rescues this defect, suggesting that C9ORF72 acts as a modulator of small GTPases in a pathway that regulates axonal actin dynamics.
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Affiliation(s)
- Rajeeve Sivadasan
- Institute of Clinical Neurobiology, University Hospital of Wuerzburg, Wuerzburg, Germany
| | | | - Carsten Drepper
- Institute of Clinical Neurobiology, University Hospital of Wuerzburg, Wuerzburg, Germany
| | - Nicolas Frank
- Institute of Clinical Neurobiology, University Hospital of Wuerzburg, Wuerzburg, Germany
| | - Sibylle Jablonka
- Institute of Clinical Neurobiology, University Hospital of Wuerzburg, Wuerzburg, Germany
| | - Anna Hansel
- Institute of Clinical Neurobiology, University Hospital of Wuerzburg, Wuerzburg, Germany
| | - Xenia Lojewski
- Department of Neurology, Technische Universität Dresden, Dresden, Germany
| | - Jared Sterneckert
- Center for Regenerative Therapies Dresden (CRTD), Technische Universität Dresden, Dresden, Germany
| | - Andreas Hermann
- Department of Neurology, Technische Universität Dresden, Dresden, Germany.,Center for Regenerative Therapies Dresden (CRTD), Technische Universität Dresden, Dresden, Germany.,German Center for Neurodegenerative Diseases (DZNE), Dresden, Germany
| | - Pamela J Shaw
- Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, Sheffield, UK
| | - Paul G Ince
- Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, Sheffield, UK
| | - Matthias Mann
- Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Felix Meissner
- Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Michael Sendtner
- Institute of Clinical Neurobiology, University Hospital of Wuerzburg, Wuerzburg, Germany
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22
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Wang D, Cheng Z, Zhao X, Li Z, Wang J, Dong A, Zhou Z, Zhang F. Association between MKL1 rs6001946 and schizophrenia in a Han Chinese population. Neurosci Lett 2016; 631:36-39. [PMID: 27507698 DOI: 10.1016/j.neulet.2016.08.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Revised: 07/16/2016] [Accepted: 08/05/2016] [Indexed: 10/21/2022]
Abstract
Megakaryoblastic leukemia 1 (MKL1) is highly expressed in the nervous system and plays a potentially principal role in neuronal migration and morphology. A recent study showed that some genetic loci within the MKL1 gene, especially single nucleotide polymorphism (SNP) rs6001946, may increase schizophrenia susceptibility. Here, we sought to determine whether the polymorphism rs6001946 was associated with schizophrenia in a Han Chinese population using the ligase detection reaction-polymerase chain reaction method to genotype SNP rs6001946 in the MKL1 gene. We observed that there was a marginally significant association between SNP rs6001946 and the risk of schizophrenia (P=0.077). Our results indicated that SNP rs6001946 of the MKL1 gene is likely a risk factor for schizophrenia, but the role of SNP rs6001946 in the development of schizophrenia in Han Chinese should be interpreted cautiously. Further studies with larger sample sizes are needed to determine the involvement of the MKL1 polymorphism in schizophrenia susceptibility.
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Affiliation(s)
- Dong Wang
- Wuxi Mental Health Center, Nanjing Medical University, Wuxi, 214151, Jiangsu Province, China
| | - Zaohuo Cheng
- Wuxi Mental Health Center, Nanjing Medical University, Wuxi, 214151, Jiangsu Province, China
| | - Xingfu Zhao
- Wuxi Mental Health Center, Nanjing Medical University, Wuxi, 214151, Jiangsu Province, China
| | - Zongchang Li
- Institute of Mental Health of the second Xiangya hospital, National Laboratory for Psychiatry Disease Diagnosis and Treatment, Key Laboratory of Psychiatry and Mental Health of Hunan Province, The Central South University, Changsha, China
| | - Jun Wang
- Wuxi Mental Health Center, Nanjing Medical University, Wuxi, 214151, Jiangsu Province, China
| | - Aiguo Dong
- Wuxi Mental Health Center, Nanjing Medical University, Wuxi, 214151, Jiangsu Province, China
| | - Zhenhe Zhou
- Wuxi Mental Health Center, Nanjing Medical University, Wuxi, 214151, Jiangsu Province, China
| | - Fuquan Zhang
- Wuxi Mental Health Center, Nanjing Medical University, Wuxi, 214151, Jiangsu Province, China.
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23
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Anastasiadou S, Knöll B. The multiple sclerosis drug fingolimod (FTY720) stimulates neuronal gene expression, axonal growth and regeneration. Exp Neurol 2016; 279:243-260. [PMID: 26980486 DOI: 10.1016/j.expneurol.2016.03.012] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Revised: 03/03/2016] [Accepted: 03/11/2016] [Indexed: 11/30/2022]
Abstract
Fingolimod (FTY720) is a new generation oral treatment for multiple sclerosis (MS). So far, FTY720 was mainly considered to target trafficking of immune cells but not brain cells such as neurons. Herein, we analyzed FTY720's potential to directly alter neuronal function. In CNS neurons, we identified a FTY720 governed gene expression response. FTY720 upregulated immediate early genes (IEGs) encoding for neuronal activity associated transcription factors such as c-Fos, FosB, Egr1 and Egr2 and induced actin cytoskeleton associated genes (actin isoforms, tropomyosin, calponin). Stimulation of primary neurons with FTY720 enhanced neurite growth and altered growth cone morphology. In accordance, FTY720 enhanced axon regeneration in mice upon facial nerve axotomy. We identified components of a FTY720 engaged signaling cascade including S1P receptors, G12/13G-proteins, RhoA-GTPases and the transcription factors SRF/MRTF. In summary, we uncovered a broader cellular and therapeutic operation mode of FTY720, suggesting beneficial FTY720 effects also on CNS neurons during MS therapy and for treatment of other neurodegenerative diseases requiring neuroprotective and neurorestorative processes.
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Affiliation(s)
- Sofia Anastasiadou
- Institute of Physiological Chemistry, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany
| | - Bernd Knöll
- Institute of Physiological Chemistry, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany.
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24
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Knierim E, Hirata H, Wolf NI, Morales-Gonzalez S, Schottmann G, Tanaka Y, Rudnik-Schöneborn S, Orgeur M, Zerres K, Vogt S, van Riesen A, Gill E, Seifert F, Zwirner A, Kirschner J, Goebel HH, Hübner C, Stricker S, Meierhofer D, Stenzel W, Schuelke M. Mutations in Subunits of the Activating Signal Cointegrator 1 Complex Are Associated with Prenatal Spinal Muscular Atrophy and Congenital Bone Fractures. Am J Hum Genet 2016; 98:473-489. [PMID: 26924529 DOI: 10.1016/j.ajhg.2016.01.006] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Accepted: 01/05/2016] [Indexed: 12/31/2022] Open
Abstract
Transcriptional signal cointegrators associate with transcription factors or nuclear receptors and coregulate tissue-specific gene transcription. We report on recessive loss-of-function mutations in two genes (TRIP4 and ASCC1) that encode subunits of the nuclear activating signal cointegrator 1 (ASC-1) complex. We used autozygosity mapping and whole-exome sequencing to search for pathogenic mutations in four families. Affected individuals presented with prenatal-onset spinal muscular atrophy (SMA), multiple congenital contractures (arthrogryposis multiplex congenita), respiratory distress, and congenital bone fractures. We identified homozygous and compound-heterozygous nonsense and frameshift TRIP4 and ASCC1 mutations that led to a truncation or the entire absence of the respective proteins and cosegregated with the disease phenotype. Trip4 and Ascc1 have identical expression patterns in 17.5-day-old mouse embryos with high expression levels in the spinal cord, brain, paraspinal ganglia, thyroid, and submandibular glands. Antisense morpholino-mediated knockdown of either trip4 or ascc1 in zebrafish disrupted the highly patterned and coordinated process of α-motoneuron outgrowth and formation of myotomes and neuromuscular junctions and led to a swimming defect in the larvae. Immunoprecipitation of the ASC-1 complex consistently copurified cysteine and glycine rich protein 1 (CSRP1), a transcriptional cofactor, which is known to be involved in spinal cord regeneration upon injury in adult zebrafish. ASCC1 mutant fibroblasts downregulated genes associated with neurogenesis, neuronal migration, and pathfinding (SERPINF1, DAB1, SEMA3D, SEMA3A), as well as with bone development (TNFRSF11B, RASSF2, STC1). Our findings indicate that the dysfunction of a transcriptional coactivator complex can result in a clinical syndrome affecting the neuromuscular system.
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Affiliation(s)
- Ellen Knierim
- Department of Neuropediatrics, Charité Universitätsmedizin Berlin, 10117 Berlin, Germany; NeuroCure Clinical Research Center, Charité Universitätsmedizin Berlin, 10117 Berlin, Germany
| | - Hiromi Hirata
- Department of Chemistry and Biological Science, College of Science and Engineering, Aoyama Gakuin University, Sagamihara 252-5258, Japan; Center for Frontier Research, National Institute of Genetics, Precursory Research for Embryonic Science and Technology, Japan Science and Technology Agency, Mishima 411-8540, Japan.
| | - Nicole I Wolf
- Department of Child Neurology, Neuroscience Campus Amsterdam, VU University Medical Center, 1007 MB Amsterdam, the Netherlands
| | - Susanne Morales-Gonzalez
- Department of Neuropediatrics, Charité Universitätsmedizin Berlin, 10117 Berlin, Germany; NeuroCure Clinical Research Center, Charité Universitätsmedizin Berlin, 10117 Berlin, Germany
| | - Gudrun Schottmann
- Department of Neuropediatrics, Charité Universitätsmedizin Berlin, 10117 Berlin, Germany; NeuroCure Clinical Research Center, Charité Universitätsmedizin Berlin, 10117 Berlin, Germany
| | - Yu Tanaka
- Department of Chemistry and Biological Science, College of Science and Engineering, Aoyama Gakuin University, Sagamihara 252-5258, Japan
| | - Sabine Rudnik-Schöneborn
- Institute of Human Genetics and University Hospital, Rheinisch-Westfälische Technische Hochschule Aachen University, 52074 Aachen, Germany; Division of Human Genetics, Medical University Innsbruck, 6020 Innsbruck, Austria
| | - Mickael Orgeur
- Max Planck Institute for Molecular Genetics, 14195 Berlin, Germany; Free University Berlin, Institute for Chemistry and Biochemistry, 14195 Berlin, Germany
| | - Klaus Zerres
- Institute of Human Genetics and University Hospital, Rheinisch-Westfälische Technische Hochschule Aachen University, 52074 Aachen, Germany
| | - Stefanie Vogt
- Medizinisches Versorgungszentrum Dr. Eberhard & Partner, 44137 Dortmund, Germany
| | - Anne van Riesen
- Department of Neuropediatrics, Charité Universitätsmedizin Berlin, 10117 Berlin, Germany
| | - Esther Gill
- Department of Neuropediatrics, Charité Universitätsmedizin Berlin, 10117 Berlin, Germany; NeuroCure Clinical Research Center, Charité Universitätsmedizin Berlin, 10117 Berlin, Germany
| | - Franziska Seifert
- Department of Neuropediatrics, Charité Universitätsmedizin Berlin, 10117 Berlin, Germany; NeuroCure Clinical Research Center, Charité Universitätsmedizin Berlin, 10117 Berlin, Germany
| | - Angelika Zwirner
- Department of Neuropediatrics, Charité Universitätsmedizin Berlin, 10117 Berlin, Germany; NeuroCure Clinical Research Center, Charité Universitätsmedizin Berlin, 10117 Berlin, Germany
| | - Janbernd Kirschner
- Department of Neuropediatrics and Muscle Disorders, University Medical Center Freiburg, 79106 Freiburg, Germany
| | - Hans Hilmar Goebel
- Department of Neuropathology, Charité Universitätsmedizin Berlin, 10117 Berlin, Germany
| | - Christoph Hübner
- Department of Neuropediatrics, Charité Universitätsmedizin Berlin, 10117 Berlin, Germany
| | - Sigmar Stricker
- Max Planck Institute for Molecular Genetics, 14195 Berlin, Germany; Free University Berlin, Institute for Chemistry and Biochemistry, 14195 Berlin, Germany
| | - David Meierhofer
- Max Planck Institute for Molecular Genetics, 14195 Berlin, Germany
| | - Werner Stenzel
- Department of Neuropathology, Charité Universitätsmedizin Berlin, 10117 Berlin, Germany
| | - Markus Schuelke
- Department of Neuropediatrics, Charité Universitätsmedizin Berlin, 10117 Berlin, Germany; NeuroCure Clinical Research Center, Charité Universitätsmedizin Berlin, 10117 Berlin, Germany.
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Abstract
UNLABELLED Understanding why adult CNS neurons fail to regenerate their axons following injury remains a central challenge of neuroscience research. A more complete appreciation of the biological mechanisms shaping the injured nervous system is a crucial prerequisite for the development of robust therapies to promote neural repair. Historically, the identification of regeneration associated signaling pathways has been impeded by the limitations of available genetic and molecular tools. As we progress into an era in which the high-throughput interrogation of gene expression is commonplace and our knowledge base of interactome data is rapidly expanding, we can now begin to assemble a more comprehensive view of the complex biology governing axon regeneration. Here, we highlight current and ongoing work featuring transcriptomic approaches toward the discovery of novel molecular mechanisms that can be manipulated to promote neural repair. SIGNIFICANCE STATEMENT Transcriptional profiling is a powerful technique with broad applications in the field of neuroscience. Recent advances such as single-cell transcriptomics, CNS cell type-specific and developmental stage-specific expression libraries are rapidly enhancing the power of transcriptomics for neuroscience applications. However, extracting biologically meaningful information from large transcriptomic datasets remains a formidable challenge. This mini-symposium will highlight current work using transcriptomic approaches to identify regulatory networks in the injured nervous system. We will discuss analytical strategies for transcriptomics data, the significance of noncoding RNA networks, and the utility of multiomic data integration. Though the studies featured here specifically focus on neural repair, the approaches highlighted in this mini-symposium will be of broad interest and utility to neuroscientists working in diverse areas of the field.
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26
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Meyer zu Reckendorf C, Anastasiadou S, Bachhuber F, Franz-Wachtel M, Macek B, Knöll B. Proteomic analysis of SRF associated transcription complexes identified TFII-I as modulator of SRF function in neurons. Eur J Cell Biol 2016; 95:42-56. [DOI: 10.1016/j.ejcb.2015.11.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Revised: 10/30/2015] [Accepted: 11/05/2015] [Indexed: 11/25/2022] Open
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Luo XJ, Huang L, van den Oord EJ, Aberg KA, Gan L, Zhao Z, Yao YG. Common variants in the MKL1 gene confer risk of schizophrenia. Schizophr Bull 2015; 41:715-27. [PMID: 25380769 PMCID: PMC4393692 DOI: 10.1093/schbul/sbu156] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Genome-wide association studies (GWAS) of schizophrenia have identified multiple risk variants with robust association signals for schizophrenia. However, these variants could explain only a small proportion of schizophrenia heritability. Furthermore, the effect size of these risk variants is relatively small (eg, most of them had an OR less than 1.2), suggesting that additional risk variants may be detected when increasing sample size in analysis. Here, we report the identification of a genome-wide significant schizophrenia risk locus at 22q13.1 by combining 2 large-scale schizophrenia cohort studies. Our meta-analysis revealed that 7 single nucleotide polymorphism (SNPs) on chromosome 22q13.1 reached the genome-wide significance level (P < 5.0×10(-8)) in the combined samples (a total of 38441 individuals). Among them, SNP rs6001946 had the most significant association with schizophrenia (P = 2.04×10(-8)). Interestingly, all 7 SNPs are in high linkage disequilibrium and located in the MKL1 gene. Expression analysis showed that MKL1 is highly expressed in human and mouse brains. We further investigated functional links between MKL1 and proteins encoded by other schizophrenia susceptibility genes in the whole human protein interaction network. We found that MKL1 physically interacts with GSK3B, a protein encoded by a well-characterized schizophrenia susceptibility gene. Collectively, our results revealed that genetic variants in MKL1 might confer risk to schizophrenia. Further investigation of the roles of MKL1 in the pathogenesis of schizophrenia is warranted.
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Affiliation(s)
- Xiong-jian Luo
- Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences & Yunnan Province, Kunming Institute of Zoology, Kunming, Yunnan, China;,*To whom correspondence should be addressed; Key Laboratory of Animal Models and Human Disease Mechanisms, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan 650223, China; tel: 86-871-65180085, fax: 86-871-65180085, e-mail:
| | - Liang Huang
- First Affiliated Hospital of Gannan Medical University, Ganzhou, Jiangxi 341000, China
| | - Edwin J. van den Oord
- Center for Biomarker Research and Personalized Medicine, Virginia Commonwealth University, Richmond, VA 23298, USA
| | - Karolina A. Aberg
- Center for Biomarker Research and Personalized Medicine, Virginia Commonwealth University, Richmond, VA 23298, USA
| | - Lin Gan
- Flaum Eye Institute and Department of Ophthalmology, University of Rochester, Rochester, NY 14642, USA
| | - Zhongming Zhao
- Departments of Biomedical Informatics and Psychiatry, Vanderbilt University School of Medicine, Nashville, TN
| | - Yong-Gang Yao
- Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences & Yunnan Province, Kunming Institute of Zoology, Kunming, Yunnan, China
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28
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Speranza L, Giuliano T, Volpicelli F, De Stefano ME, Lombardi L, Chambery A, Lacivita E, Leopoldo M, Bellenchi GC, di Porzio U, Crispino M, Perrone-Capano C. Activation of 5-HT7 receptor stimulates neurite elongation through mTOR, Cdc42 and actin filaments dynamics. Front Behav Neurosci 2015; 9:62. [PMID: 25814944 PMCID: PMC4356071 DOI: 10.3389/fnbeh.2015.00062] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2014] [Accepted: 02/23/2015] [Indexed: 12/02/2022] Open
Abstract
Recent studies have indicated that the serotonin receptor subtype 7 (5-HT7R) plays a crucial role in shaping neuronal morphology during embryonic and early postnatal life. Here we show that pharmacological stimulation of 5-HT7R using a highly selective agonist, LP-211, enhances neurite outgrowth in neuronal primary cultures from the cortex, hippocampus and striatal complex of embryonic mouse brain, through multiple signal transduction pathways. All these signaling systems, involving mTOR, the Rho GTPase Cdc42, Cdk5, and ERK, are known to converge on the reorganization of cytoskeletal proteins that subserve neurite outgrowth. Indeed, our data indicate that neurite elongation stimulated by 5-HT7R is modulated by drugs affecting actin polymerization. In addition, we show, by 2D Western blot analyses, that treatment of neuronal cultures with LP-211 alters the expression profile of cofilin, an actin binding protein involved in microfilaments dynamics. Furthermore, by using microfluidic chambers that physically separate axons from the soma and dendrites, we demonstrate that agonist-dependent activation of 5-HT7R stimulates axonal elongation. Our results identify for the first time several signal transduction pathways, activated by stimulation of 5-HT7R, that converge to promote cytoskeleton reorganization and consequent modulation of axonal elongation. Therefore, the activation of 5-HT7R might represent one of the key elements regulating CNS connectivity and plasticity during development.
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Affiliation(s)
- Luisa Speranza
- Department of Biology, University of Naples Federico II Naples, Italy ; Institute of Genetics and Biophysics "Adriano Buzzati Traverso", CNR Naples, Italy
| | - Teresa Giuliano
- Institute of Genetics and Biophysics "Adriano Buzzati Traverso", CNR Naples, Italy
| | - Floriana Volpicelli
- Institute of Genetics and Biophysics "Adriano Buzzati Traverso", CNR Naples, Italy ; Department of Pharmacy, University of Naples Federico II Naples, Italy
| | - M Egle De Stefano
- Department of Biology and Biotechnology "Charles Darwin", Istituto Pasteur Fondazione Cenci Bolognetti, University of Rome La Sapienza Rome, Italy
| | - Loredana Lombardi
- Department of Biology and Biotechnology "Charles Darwin", Istituto Pasteur Fondazione Cenci Bolognetti, University of Rome La Sapienza Rome, Italy
| | - Angela Chambery
- Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, Second University of Naples Naples, Italy ; IRCCS, Multimedica Milano, Italy
| | - Enza Lacivita
- Department of Pharmacy - Pharmaceutical Sciences, University of Bari Bari, Italy
| | - Marcello Leopoldo
- Department of Pharmacy - Pharmaceutical Sciences, University of Bari Bari, Italy
| | - Gian C Bellenchi
- Institute of Genetics and Biophysics "Adriano Buzzati Traverso", CNR Naples, Italy
| | - Umberto di Porzio
- Institute of Genetics and Biophysics "Adriano Buzzati Traverso", CNR Naples, Italy
| | - Marianna Crispino
- Department of Biology, University of Naples Federico II Naples, Italy
| | - Carla Perrone-Capano
- Department of Biology, University of Naples Federico II Naples, Italy ; Institute of Genetics and Biophysics "Adriano Buzzati Traverso", CNR Naples, Italy
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29
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Anastasiadou S, Liebenehm S, Sinske D, Meyer zu Reckendorf C, Moepps B, Nordheim A, Knöll B. Neuronal expression of the transcription factor serum response factor modulates myelination in a mouse multiple sclerosis model. Glia 2015; 63:958-76. [PMID: 25639799 DOI: 10.1002/glia.22794] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Revised: 01/08/2015] [Accepted: 01/08/2015] [Indexed: 12/14/2022]
Abstract
In multiple sclerosis (MS), neurons in addition to inflammatory cells are now considered to mediate disease origin and progression. So far, molecular and cellular mechanisms of neuronal MS contributions are poorly understood. Herein we analyzed whether neuron-restricted signaling by the neuroprotective transcription factor serum response factor (SRF) modulates de- and remyelination in a rodent MS model. In the mouse cuprizone model, neuron- (Srf (flox/flox;CaMKCreERT2)) but not glia-specific (Srf (flox/flox;PlpCreERT2)) SRF depletion impaired demyelination suggesting impaired debris clearance by astrocytes and microglia. This supports an important role of SRF expression in neurons but not oligodendrocytes in de- and remyelination. During remyelination, NG2- and OLIG2-positive cells of the oligodendrocyte lineage as well as de novo mRNA synthesis of myelin genes were also reduced in neuron-specific Srf mutants. Using the stripe assay, we demonstrate that cortices of cuprizone-fed wild-type mice elicited astrocyte and microglia activation whereas this was abrogated in cuprizone-fed neuron-specific Srf mutants. We identified CCL chemokines (e.g. CCL2) as neuron-derived SRF-regulated paracrine signals rescuing immune cell activation upon neuronal SRF deletion. In summary, we uncovered important roles of neurons and neuronally expressed SRF in MS associated de- and remyelination.
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Affiliation(s)
- Sofia Anastasiadou
- Institute of Physiological Chemistry, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany
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30
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Stern S, Knöll B. CNS axon regeneration inhibitors stimulate an immediate early gene response via MAP kinase-SRF signaling. Mol Brain 2014; 7:86. [PMID: 25406759 PMCID: PMC4243276 DOI: 10.1186/s13041-014-0086-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Accepted: 11/11/2014] [Indexed: 12/24/2022] Open
Abstract
Background CNS axon regeneration inhibitors such as Nogo and CSPGs (Chondroitin Sulfate Proteoglycans) are major extrinsic factors limiting outgrowth of severed nerve fibers. However, knowledge on intracellular signaling cascades and gene expression programs activated by these inhibitors in neurons is sparse. Herein we studied intracellular signaling cascades activated by total myelin, Nogo and CSPGs in primary mouse CNS neurons. Results Total myelin, Nogo and CSPGs stimulated gene expression activity of the serum response factor (SRF), a central gene regulator of immediate early (IEG) and actin cytoskeletal gene transcription. As demonstrated by pharmacological interference, SRF-mediated IEG activation by myelin, Nogo or CSPGs depended on MAP kinase, to a lesser extent on Rho-GTPase but not on PKA signaling. Stimulation of neurons with all three axon growth inhibitors activated the MAP kinase ERK. In addition to ERK activation, myelin activated the IEG c-Fos, an important checkpoint of neuronal survival vs. apoptosis. Employing Srf deficient neurons revealed that myelin-induced IEG activation requires SRF. This suggests an SRF function in mediating neuronal signaling evoked by axon regeneration associated inhibitors. Besides being a signaling target of axon growth inhibitors, we show that constitutively-active SRF-VP16 can be employed to circumvent neurite growth inhibition imposed by myelin, Nogo and CSPGs. Conclusion In sum, our data demonstrate that axon regeneration inhibitors such as Nogo trigger gene expression programs including an SRF-dependent IEG response via MAP kinases and Rho-GTPases.
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Affiliation(s)
- Sina Stern
- Department Molecular Biology, Eberhard-Karls-University Tübingen, Interfaculty Institute for Cell Biology, Auf der Morgenstelle 15, 72076, Tübingen, Germany. .,Current address: German Centre for Neurodegenerative Diseases (DZNE), Ludwig-Erhard-Allee 2, 53175, Bonn, Germany.
| | - Bernd Knöll
- Department Molecular Biology, Eberhard-Karls-University Tübingen, Interfaculty Institute for Cell Biology, Auf der Morgenstelle 15, 72076, Tübingen, Germany. .,Current address: Ulm University, Institute for Physiological Chemistry, 89081, Ulm, Germany.
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Li L, Zhang W, Chai X, Zhang Q, Xie J, Chen S, Zhao S. Neuronal maturation and laminar formation in the chicken optic tectum are accompanied by the transition of phosphorylated cofilin from cytoplasm to nucleus. Gene Expr Patterns 2014; 16:75-85. [PMID: 25290739 DOI: 10.1016/j.gep.2014.09.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Revised: 09/23/2014] [Accepted: 09/25/2014] [Indexed: 11/17/2022]
Abstract
Laminar formation in the chicken optic tectum requires processes that coordinate proliferation, migration and differentiation of neurons, in which the dynamics of actin filaments are crucial. Cofilin plays pivotal roles in regulating actin arrangement via its phosphorylation on Ser3. Given poor studies on the profile of phosphorylated cofilin (p-cofilin) in the developing tectum, we investigated its expression pattern. As determined by immunofluorescence histochemistry and western blotting, p-cofilin could be detected in most tectal layers except for the neural epithelium. In addition, we found p-cofilin was expressed both in the cytoplasm and the nucleus. During development, the expression of the cytoplasmic p-cofilin was decreasing and the nuclear p-cofilin was gradually increasing, but the total level of p-cofilin was down regulated. Double-labeling experiments revealed that the nuclear p-cofilin could be labeled in mature neurons but undetected in immature neurons. Furthermore, the number of cells co-stained with nuclear p-cofilin and NeuN was up-regulated during lamination and 60% cells were detected to be mature neurons that can express nuclear p-cofilin just at the first appearance of completed laminae. Our results demonstrate that the maturation of neurons is accompanied by this cytoplasm-to-nucleus transition of p-cofilin, and the nuclear p-cofilin can work effectively as a marker in the laminar formation of the chicken optic tectum.
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Affiliation(s)
- Lingling Li
- College of Veterinary Medicine, Northwest A&F University, Yangling, 712100 Shaanxi, China
| | - Wei Zhang
- College of Veterinary Medicine, Northwest A&F University, Yangling, 712100 Shaanxi, China
| | - Xuejun Chai
- Institute for Structural Neurobiology, Center for Molecular Neurobiology Hamburg (ZMNH), Universitätsklinikum Hamburg-Eppendorf, Hamburg, Germany
| | - Qi Zhang
- College of Veterinary Medicine, Northwest A&F University, Yangling, 712100 Shaanxi, China
| | - Jiongfang Xie
- College of Veterinary Medicine, Northwest A&F University, Yangling, 712100 Shaanxi, China
| | - Shulin Chen
- College of Veterinary Medicine, Northwest A&F University, Yangling, 712100 Shaanxi, China
| | - Shanting Zhao
- College of Veterinary Medicine, Northwest A&F University, Yangling, 712100 Shaanxi, China.
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Regulating Set-β's Subcellular Localization Toggles Its Function between Inhibiting and Promoting Axon Growth and Regeneration. J Neurosci 2014; 34:7361-74. [PMID: 24849368 DOI: 10.1523/jneurosci.3658-13.2014] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
The failure of the CNS neurons to regenerate axons after injury or stroke is a major clinical problem. Transcriptional regulators like Set-β are well positioned to regulate intrinsic axon regeneration capacity, which declines developmentally in maturing CNS neurons. Set-β also functions at cellular membranes and its subcellular localization is disrupted in Alzheimer's disease, but many of its biological mechanisms have not been explored in neurons. We found that Set-β was upregulated postnatally in CNS neurons, and was primarily localized to the nucleus but was also detected in the cytoplasm and adjacent to the plasma membrane. Remarkably, nuclear Set-β suppressed, whereas Set-β localized to cytoplasmic membranes promoted neurite growth in rodent retinal ganglion cells and hippocampal neurons. Mimicking serine 9 phosphorylation, as found in Alzheimer's disease brains, delayed nuclear import and furthermore blocked the ability of nuclear Set-β to suppress neurite growth. We also present data on gene regulation and protein binding partner recruitment by Set-β in primary neurons, raising the hypothesis that nuclear Set-β may preferentially regulate gene expression whereas Set-β at cytoplasmic membranes may regulate unique cofactors, including PP2A, which we show also regulates axon growth in vitro. Finally, increasing recruitment of Set-β to cellular membranes promoted adult rat optic nerve axon regeneration after injury in vivo. Thus, Set-β differentially regulates axon growth and regeneration depending on subcellular localization and phosphorylation.
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Abstract
The growth of axons is an intricately regulated process involving intracellular signaling cascades and gene transcription. We had previously shown that the stimulus-dependent transcription factor, serum response factor (SRF), plays a critical role in regulating axon growth in the mammalian brain. However, the molecular mechanisms underlying SRF-dependent axon growth remains unknown. Here we report that SRF is phosphorylated and activated by GSK-3 to promote axon outgrowth in mouse hippocampal neurons. GSK-3 binds to and directly phosphorylates SRF on a highly conserved serine residue. This serine phosphorylation is necessary for SRF activity and for its interaction with MKL-family cofactors, MKL1 and MKL2, but not with TCF-family cofactor, ELK-1. Axonal growth deficits caused by GSK-3 inhibition could be rescued by expression of a constitutively active SRF. The SRF target gene and actin-binding protein, vinculin, is sufficient to overcome the axonal growth deficits of SRF-deficient and GSK-3-inhibited neurons. Furthermore, short hairpin RNA-mediated knockdown of vinculin also attenuated axonal growth. Thus, our findings reveal a novel phosphorylation and activation of SRF by GSK-3 that is critical for SRF-dependent axon growth in mammalian central neurons.
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