1
|
Wu S, Liu P, Cvetanovic M, Lin W. Endoplasmic reticulum associated degradation preserves neurons viability by maintaining endoplasmic reticulum homeostasis. Front Neurosci 2024; 18:1437854. [PMID: 39135735 PMCID: PMC11317260 DOI: 10.3389/fnins.2024.1437854] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2024] [Accepted: 07/19/2024] [Indexed: 08/15/2024] Open
Abstract
Endoplasmic reticulum-associated degradation (ERAD) is a principal quality-control mechanism responsible for targeting misfolded ER proteins for cytosolic degradation. Evidence suggests that impairment of ERAD contributes to neuron dysfunction and death in neurodegenerative diseases, many of which are characterized by accumulation and aggregation of misfolded proteins. However, the physiological role of ERAD in neurons remains unclear. The Sel1L-Hrd1 complex consisting of the E3 ubiquitin ligase Hrd1 and its adaptor protein Sel1L is the best-characterized ERAD machinery. Herein, we showed that Sel1L deficiency specifically in neurons of adult mice impaired the ERAD activity of the Sel1L-Hrd1 complex and led to disruption of ER homeostasis, ER stress and activation of the unfold protein response (UPR). Adult mice with Sel1L deficiency in neurons exhibited weight loss and severe motor dysfunction, and rapidly succumbed to death. Interestingly, Sel1L deficiency in neurons caused global brain atrophy, particularly cerebellar and hippocampal atrophy, in adult mice. Moreover, we found that cerebellar and hippocampal atrophy in these mice resulted from degeneration of Purkinje neurons and hippocampal neurons, respectively. These findings indicate that ERAD is required for maintaining ER homeostasis and the viability and function of neurons in adults under physiological conditions.
Collapse
Affiliation(s)
- Shuangchan Wu
- Department of Neuroscience, University of Minnesota, Minneapolis, MN, United States
- Institute for Translational Neuroscience, University of Minnesota, Minneapolis, MN, United States
| | - Pingting Liu
- Department of Neuroscience, University of Minnesota, Minneapolis, MN, United States
- Institute for Translational Neuroscience, University of Minnesota, Minneapolis, MN, United States
| | - Marija Cvetanovic
- Department of Neuroscience, University of Minnesota, Minneapolis, MN, United States
- Institute for Translational Neuroscience, University of Minnesota, Minneapolis, MN, United States
| | - Wensheng Lin
- Department of Neuroscience, University of Minnesota, Minneapolis, MN, United States
- Institute for Translational Neuroscience, University of Minnesota, Minneapolis, MN, United States
| |
Collapse
|
2
|
Wang Y, Halawani D, Estill M, Ramakrishnan A, Shen L, Friedel RH, Zou H. Aryl hydrocarbon receptor restricts axon regeneration of DRG neurons in response to injury. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.04.565649. [PMID: 37961567 PMCID: PMC10635160 DOI: 10.1101/2023.11.04.565649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
Injured neurons sense environmental cues to balance neural protection and axon regeneration, but the mechanisms are unclear. Here, we unveil aryl hydrocarbon receptor (AhR), a ligand-activated bHLH-PAS transcription factor, as molecular sensor and key regulator of acute stress response at the expense of axon regeneration. We demonstrate responsiveness of DRG sensory neurons to ligand-mediated AhR signaling, which functions to inhibit axon regeneration. Ahr deletion mimics the conditioning lesion in priming DRG to initiate axonogenesis gene programs; upon peripheral axotomy, Ahr ablation suppresses inflammation and stress signaling while augmenting pro-growth pathways. Moreover, comparative transcriptomics revealed signaling interactions between AhR and HIF-1α, two structurally related bHLH-PAS α units that share the dimerization partner Arnt/HIF-1β. Functional assays showed that the growth advantage of AhR-deficient DRG neurons requires HIF-1α; but in the absence of Arnt, DRG neurons can still mount a regenerative response. We further unveil a link between bHLH-PAS transcription factors and DNA hydroxymethylation in response to peripheral axotomy, while neuronal single cell RNA-seq analysis revealed a link of the AhR regulon to RNA polymerase III regulation and integrated stress response (ISR). Altogether, AhR activation favors stress coping and inflammation at the expense of axon regeneration; targeting AhR can enhance nerve repair.
Collapse
Affiliation(s)
- Yiqun Wang
- Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, USA
- Current address: Sport Medicine Center, Honghui Hospital, Xi’an Jiaotong University, Xi’an, China
| | - Dalia Halawani
- Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, USA
| | - Molly Estill
- Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, USA
| | - Aarthi Ramakrishnan
- Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, USA
| | - Li Shen
- Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, USA
| | - Roland H. Friedel
- Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, USA
- Department of Neurosurgery, Icahn School of Medicine at Mount Sinai, New York, USA
| | - Hongyan Zou
- Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, USA
- Department of Neurosurgery, Icahn School of Medicine at Mount Sinai, New York, USA
| |
Collapse
|
3
|
Chang C, Sell LB, Shi Q, Bhat MA. Mouse models of human CNTNAP1-associated congenital hypomyelinating neuropathy and genetic restoration of murine neurological deficits. Cell Rep 2023; 42:113274. [PMID: 37862170 PMCID: PMC10873044 DOI: 10.1016/j.celrep.2023.113274] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 08/14/2023] [Accepted: 09/28/2023] [Indexed: 10/22/2023] Open
Abstract
The Contactin-associated protein 1 (Cntnap1) mouse mutants fail to establish proper axonal domains in myelinated axons. Human CNTNAP1 mutations are linked to hypomyelinating neuropathy-3, which causes severe neurological deficits. To understand the human neuropathology and to model human CNTNAP1C323R and CNTNAP1R764C mutations, we generated Cntnap1C324R and Cntnap1R765C mouse mutants, respectively. Both Cntnap1 mutants show weight loss, reduced nerve conduction, and progressive motor dysfunction. The paranodal ultrastructure shows everted myelin loops and the absence of axo-glial junctions. Biochemical analysis reveals that these Cntnap1 mutant proteins are nearly undetectable in the paranodes, have reduced surface expression and stability, and are retained in the neuronal soma. Postnatal transgenic expression of Cntnap1 in the mutant backgrounds rescues the phenotypes and restores the organization of axonal domains with improved motor function. This study uncovers the mechanistic impact of two human CNTNAP1 mutations in a mouse model and provides proof of concept for gene therapy for CNTNAP1 patients.
Collapse
Affiliation(s)
- Cheng Chang
- Department of Cellular and Integrative Physiology University of Texas Health Science Center San Antonio, 7703 Floyd Curl Drive, San Antonio, TX 78229, USA; The Second Xiangya Hospital of Central South University, Changsha 410011, Hunan, China
| | - Lacey B Sell
- Department of Cellular and Integrative Physiology University of Texas Health Science Center San Antonio, 7703 Floyd Curl Drive, San Antonio, TX 78229, USA; IBMS Neuroscience Graduate Program, Joe R. and Teresa Lozano Long School of Medicine, University of Texas Health Science Center San Antonio, 7703 Floyd Curl Drive, San Antonio, TX 78229, USA
| | - Qian Shi
- Department of Cellular and Integrative Physiology University of Texas Health Science Center San Antonio, 7703 Floyd Curl Drive, San Antonio, TX 78229, USA; IBMS Neuroscience Graduate Program, Joe R. and Teresa Lozano Long School of Medicine, University of Texas Health Science Center San Antonio, 7703 Floyd Curl Drive, San Antonio, TX 78229, USA
| | - Manzoor A Bhat
- Department of Cellular and Integrative Physiology University of Texas Health Science Center San Antonio, 7703 Floyd Curl Drive, San Antonio, TX 78229, USA; IBMS Neuroscience Graduate Program, Joe R. and Teresa Lozano Long School of Medicine, University of Texas Health Science Center San Antonio, 7703 Floyd Curl Drive, San Antonio, TX 78229, USA.
| |
Collapse
|
4
|
Halawani D, Wang Y, Ramakrishnan A, Estill M, He X, Shen L, Friedel RH, Zou H. Circadian clock regulator Bmal1 gates axon regeneration via Tet3 epigenetics in mouse sensory neurons. Nat Commun 2023; 14:5165. [PMID: 37620297 PMCID: PMC10449865 DOI: 10.1038/s41467-023-40816-7] [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: 10/25/2022] [Accepted: 08/11/2023] [Indexed: 08/26/2023] Open
Abstract
Axon regeneration of dorsal root ganglia (DRG) neurons after peripheral axotomy involves reconfiguration of gene regulatory circuits to establish regenerative gene programs. However, the underlying mechanisms remain unclear. Here, through an unbiased survey, we show that the binding motif of Bmal1, a central transcription factor of the circadian clock, is enriched in differentially hydroxymethylated regions (DhMRs) of mouse DRG after peripheral lesion. By applying conditional deletion of Bmal1 in neurons, in vitro and in vivo neurite outgrowth assays, as well as transcriptomic profiling, we demonstrate that Bmal1 inhibits axon regeneration, in part through a functional link with the epigenetic factor Tet3. Mechanistically, we reveal that Bmal1 acts as a gatekeeper of neuroepigenetic responses to axonal injury by limiting Tet3 expression and restricting 5hmC modifications. Bmal1-regulated genes not only concern axon growth, but also stress responses and energy homeostasis. Furthermore, we uncover an epigenetic rhythm of diurnal oscillation of Tet3 and 5hmC levels in DRG neurons, corresponding to time-of-day effect on axon growth potential. Collectively, our studies demonstrate that targeting Bmal1 enhances axon regeneration.
Collapse
Affiliation(s)
- Dalia Halawani
- Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Yiqun Wang
- Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Orthopedics, Second Affiliated Hospital of Xi'an Jiaotong University, Shaanxi, China
| | - Aarthi Ramakrishnan
- Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Molly Estill
- Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Xijing He
- Department of Orthopedics, Second Affiliated Hospital of Xi'an Jiaotong University, Shaanxi, China
- Department of Orthopedics, Xi'an International Medical Center Hospital, Xi'an, China
| | - Li Shen
- Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Roland H Friedel
- Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Neurosurgery, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Hongyan Zou
- Nash Family Department of Neuroscience, Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
- Department of Neurosurgery, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
| |
Collapse
|
5
|
Liu P, Karim MR, Covelo A, Yue Y, Lee MK, Lin W. The UPR Maintains Proteostasis and the Viability and Function of Hippocampal Neurons in Adult Mice. Int J Mol Sci 2023; 24:11542. [PMID: 37511300 PMCID: PMC10380539 DOI: 10.3390/ijms241411542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2023] [Revised: 07/05/2023] [Accepted: 07/13/2023] [Indexed: 07/30/2023] Open
Abstract
The unfolded protein response (UPR), which comprises three branches: PERK, ATF6α, and IRE1, is a major mechanism for maintaining cellular proteostasis. Many studies show that the UPR is a major player in regulating neuron viability and function in various neurodegenerative diseases; however, its role in neurodegeneration is highly controversial. Moreover, while evidence suggests activation of the UPR in neurons under normal conditions, deficiency of individual branches of the UPR has no major effect on brain neurons in animals. It remains unclear whether or how the UPR participates in regulating neuronal proteostasis under normal and disease conditions. To determine the physiological role of the UPR in neurons, we generated mice with double deletion of PERK and ATF6α in neurons. We found that inactivation of PERK and ATF6α in neurons caused lysosomal dysfunction (as evidenced by decreased expression of the V0a1 subunit of v-ATPase and decreased activation of cathepsin D), impairment of autophagic flux (as evidenced by increased ratio of LC3-II/LC3-I and increased p62 level), and accumulation of p-tau and Aβ42 in the hippocampus, and led to impairment of spatial memory, impairment of hippocampal LTP, and hippocampal degeneration in adult mice. These results suggest that the UPR is required for maintaining neuronal proteostasis (particularly tau and Aβ homeostasis) and the viability and function of neurons in the hippocampus of adult mice.
Collapse
Affiliation(s)
- Pingting Liu
- Department of Neuroscience, University of Minnesota, Minneapolis, MN 55455, USA
- Institute for Translational Neuroscience, University of Minnesota, 2101 6th Street SE, WMBB4-140, Minneapolis, MN 55455, USA
| | - Md Razaul Karim
- Department of Neuroscience, University of Minnesota, Minneapolis, MN 55455, USA
- Institute for Translational Neuroscience, University of Minnesota, 2101 6th Street SE, WMBB4-140, Minneapolis, MN 55455, USA
| | - Ana Covelo
- Department of Neuroscience, University of Minnesota, Minneapolis, MN 55455, USA
| | - Yuan Yue
- Department of Neuroscience, University of Minnesota, Minneapolis, MN 55455, USA
- Institute for Translational Neuroscience, University of Minnesota, 2101 6th Street SE, WMBB4-140, Minneapolis, MN 55455, USA
| | - Michael K Lee
- Department of Neuroscience, University of Minnesota, Minneapolis, MN 55455, USA
- Institute for Translational Neuroscience, University of Minnesota, 2101 6th Street SE, WMBB4-140, Minneapolis, MN 55455, USA
| | - Wensheng Lin
- Department of Neuroscience, University of Minnesota, Minneapolis, MN 55455, USA
- Institute for Translational Neuroscience, University of Minnesota, 2101 6th Street SE, WMBB4-140, Minneapolis, MN 55455, USA
| |
Collapse
|
6
|
Bhaskaran S, Kumar G, Thadathil N, Piekarz KM, Mohammed S, Lopez SD, Qaisar R, Walton D, Brown JL, Murphy A, Smith N, Saunders D, Beckstead MJ, Plafker S, Lewis TL, Towner R, Deepa SS, Richardson A, Axtell RC, Van Remmen H. Neuronal deletion of MnSOD in mice leads to demyelination, inflammation and progressive paralysis that mimics phenotypes associated with progressive multiple sclerosis. Redox Biol 2023; 59:102550. [PMID: 36470129 PMCID: PMC9720104 DOI: 10.1016/j.redox.2022.102550] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 11/17/2022] [Accepted: 11/21/2022] [Indexed: 11/27/2022] Open
Abstract
Neuronal oxidative stress has been implicated in aging and neurodegenerative disease. Here we investigated the impact of elevated oxidative stress induced in mouse spinal cord by deletion of Mn-Superoxide dismutase (MnSOD) using a neuron specific Cre recombinase in Sod2 floxed mice (i-mn-Sod2 KO). Sod2 deletion in spinal cord neurons was associated with mitochondrial alterations and peroxide generation. Phenotypically, i-mn-Sod2 KO mice experienced hindlimb paralysis and clasping behavior associated with extensive demyelination and reduced nerve conduction velocity, axonal degeneration, enhanced blood brain barrier permeability, elevated inflammatory cytokines, microglia activation, infiltration of neutrophils and necroptosis in spinal cord. In contrast, spinal cord motor neuron number, innervation of neuromuscular junctions, muscle mass, and contractile function were not altered. Overall, our findings show that loss of MnSOD in spinal cord promotes a phenotype of demyelination, inflammation and progressive paralysis that mimics phenotypes associated with progressive multiple sclerosis.
Collapse
Affiliation(s)
- Shylesh Bhaskaran
- Aging & Metabolism Research Program, Oklahoma Medical Research Foundation, OK, USA
| | - Gaurav Kumar
- Arthritis & Clinical Immunology, Oklahoma Medical Research Foundation, OK, USA
| | - Nidheesh Thadathil
- Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, OK, USA
| | - Katarzyna M Piekarz
- Aging & Metabolism Research Program, Oklahoma Medical Research Foundation, OK, USA
| | - Sabira Mohammed
- Stephenson Cancer Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | | | - Rizwan Qaisar
- Aging & Metabolism Research Program, Oklahoma Medical Research Foundation, OK, USA
| | - Dorothy Walton
- Aging & Metabolism Research Program, Oklahoma Medical Research Foundation, OK, USA
| | - Jacob L Brown
- Aging & Metabolism Research Program, Oklahoma Medical Research Foundation, OK, USA; Oklahoma City VA Medical Center, Oklahoma City, OK, USA
| | - Ashley Murphy
- Aging & Metabolism Research Program, Oklahoma Medical Research Foundation, OK, USA
| | - Nataliya Smith
- Advanced Magnetic Resonance Center, Oklahoma Medical Research Foundation, OK, USA
| | - Debra Saunders
- Advanced Magnetic Resonance Center, Oklahoma Medical Research Foundation, OK, USA
| | - Michael J Beckstead
- Aging & Metabolism Research Program, Oklahoma Medical Research Foundation, OK, USA; Oklahoma City VA Medical Center, Oklahoma City, OK, USA
| | - Scott Plafker
- Aging & Metabolism Research Program, Oklahoma Medical Research Foundation, OK, USA
| | - Tommy L Lewis
- Aging & Metabolism Research Program, Oklahoma Medical Research Foundation, OK, USA
| | - Rheal Towner
- Advanced Magnetic Resonance Center, Oklahoma Medical Research Foundation, OK, USA
| | - Sathyaseelan S Deepa
- Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, OK, USA; Stephenson Cancer Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Arlan Richardson
- Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, OK, USA; Stephenson Cancer Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA; Oklahoma City VA Medical Center, Oklahoma City, OK, USA
| | - Robert C Axtell
- Arthritis & Clinical Immunology, Oklahoma Medical Research Foundation, OK, USA.
| | - Holly Van Remmen
- Aging & Metabolism Research Program, Oklahoma Medical Research Foundation, OK, USA; Oklahoma City VA Medical Center, Oklahoma City, OK, USA.
| |
Collapse
|
7
|
Arias A, Manubens-Gil L, Dierssen M. Fluorescent transgenic mouse models for whole-brain imaging in health and disease. Front Mol Neurosci 2022; 15:958222. [PMID: 36211979 PMCID: PMC9538927 DOI: 10.3389/fnmol.2022.958222] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 08/08/2022] [Indexed: 11/25/2022] Open
Abstract
A paradigm shift is occurring in neuroscience and in general in life sciences converting biomedical research from a descriptive discipline into a quantitative, predictive, actionable science. Living systems are becoming amenable to quantitative description, with profound consequences for our ability to predict biological phenomena. New experimental tools such as tissue clearing, whole-brain imaging, and genetic engineering technologies have opened the opportunity to embrace this new paradigm, allowing to extract anatomical features such as cell number, their full morphology, and even their structural connectivity. These tools will also allow the exploration of new features such as their geometrical arrangement, within and across brain regions. This would be especially important to better characterize brain function and pathological alterations in neurological, neurodevelopmental, and neurodegenerative disorders. New animal models for mapping fluorescent protein-expressing neurons and axon pathways in adult mice are key to this aim. As a result of both developments, relevant cell populations with endogenous fluorescence signals can be comprehensively and quantitatively mapped to whole-brain images acquired at submicron resolution. However, they present intrinsic limitations: weak fluorescent signals, unequal signal strength across the same cell type, lack of specificity of fluorescent labels, overlapping signals in cell types with dense labeling, or undetectable signal at distal parts of the neurons, among others. In this review, we discuss the recent advances in the development of fluorescent transgenic mouse models that overcome to some extent the technical and conceptual limitations and tradeoffs between different strategies. We also discuss the potential use of these strains for understanding disease.
Collapse
Affiliation(s)
- Adrian Arias
- Department of System Biology, Centre for Genomic Regulation, The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Linus Manubens-Gil
- Institute for Brain and Intelligence, Southeast University, Nanjing, China
| | - Mara Dierssen
- Department of System Biology, Centre for Genomic Regulation, The Barcelona Institute of Science and Technology, Barcelona, Spain
- Department of Experimental and Health Sciences, University Pompeu Fabra, Barcelona, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Barcelona, Spain
- *Correspondence: Mara Dierssen,
| |
Collapse
|
8
|
Evans RC, Chen L, Na R, Yoo K, Ran Q. The Gpx4NIKO Mouse Is a Versatile Model for Testing Interventions Targeting Ferroptotic Cell Death of Spinal Motor Neurons. Neurotox Res 2022; 40:373-383. [PMID: 35043381 PMCID: PMC9035057 DOI: 10.1007/s12640-021-00469-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 12/09/2021] [Accepted: 12/27/2021] [Indexed: 12/13/2022]
Abstract
The degeneration and death of motor neurons lead to motor neuron diseases such as amyotrophic lateral sclerosis (ALS). Although the exact mechanism by which motor neuron degeneration occurs is not well understood, emerging evidence implicates the involvement of ferroptosis, an iron-dependent oxidative mode of cell death. We reported previously that treating Gpx4NIKO mice with tamoxifen to ablate the ferroptosis regulator glutathione peroxidase 4 (GPX4) in neurons produces a severe paralytic model resembling an accelerated form of ALS that appears to be caused by ferroptotic cell death of spinal motor neurons. In this study, in support of the role of ferroptosis in this model, we found that the paralytic symptoms and spinal motor neuron death of Gpx4NIKO mice were attenuated by a chemical inhibitor of ferroptosis. In addition, we observed that the paralytic symptoms of Gpx4NIKO mice were malleable and could be tapered by lowering the dose of tamoxifen, allowing for the generation of a mild paralytic model without a rapid onset of death. We further used both models to evaluate mitochondrial reactive oxygen species (mtROS) in the ferroptosis of spinal motor neurons and showed that overexpression of peroxiredoxin 3, a mitochondrial antioxidant defense enzyme, ameliorated symptoms of the mild but not the severe model of the Gpx4NIKO mice. Our results thus indicate that the Gpx4NIKO mouse is a versatile model for testing interventions that target ferroptotic death of spinal motor neurons in vivo.
Collapse
Affiliation(s)
- Robert Cole Evans
- Department of Cell Systems & Anatomy, University of Texas Health San Antonio, San Antonio, TX, USA
| | - Liuji Chen
- Department of Cell Systems & Anatomy, University of Texas Health San Antonio, San Antonio, TX, USA
| | - Ren Na
- Department of Cell Systems & Anatomy, University of Texas Health San Antonio, San Antonio, TX, USA
| | - Kwangsun Yoo
- Department of Cell Systems & Anatomy, University of Texas Health San Antonio, San Antonio, TX, USA
| | - Qitao Ran
- Department of Cell Systems & Anatomy, University of Texas Health San Antonio, San Antonio, TX, USA.
- Research Service, South Texas Veterans Health Care System, San Antonio, TX, USA.
| |
Collapse
|
9
|
Robert BJA, Moreau MM, Dos Santos Carvalho S, Barthet G, Racca C, Bhouri M, Quiedeville A, Garret M, Atchama B, Al Abed AS, Guette C, Henderson DJ, Desmedt A, Mulle C, Marighetto A, Montcouquiol M, Sans N. Vangl2 in the Dentate Network Modulates Pattern Separation and Pattern Completion. Cell Rep 2021; 31:107743. [PMID: 32521268 PMCID: PMC7296350 DOI: 10.1016/j.celrep.2020.107743] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 03/13/2020] [Accepted: 05/15/2020] [Indexed: 12/13/2022] Open
Abstract
The organization of spatial information, including pattern completion and pattern separation processes, relies on the hippocampal circuits, yet the molecular and cellular mechanisms underlying these two processes are elusive. Here, we find that loss of Vangl2, a core PCP gene, results in opposite effects on pattern completion and pattern separation processes. Mechanistically, we show that Vangl2 loss maintains young postmitotic granule cells in an immature state, providing increased cellular input for pattern separation. The genetic ablation of Vangl2 disrupts granule cell morpho-functional maturation and further prevents CaMKII and GluA1 phosphorylation, disrupting the stabilization of AMPA receptors. As a functional consequence, LTP at lateral perforant path-GC synapses is impaired, leading to defects in pattern completion behavior. In conclusion, we show that Vangl2 exerts a bimodal regulation on young and mature GCs, and its disruption leads to an imbalance in hippocampus-dependent pattern completion and separation processes. Vangl2-dependent PCP signaling controls granule cell maturation and network integration Vangl2 stabilizes GluA1-containing receptors at the surface of dendritic spines Granule cells require Vangl2-dependent signaling to elicit LTP Vangl2 loss has opposite functional effects on pattern completion/separation processes
Collapse
Affiliation(s)
- Benjamin J A Robert
- INSERM, Neurocentre Magendie, U1215, 33000 Bordeaux, France; Université Bordeaux, Neurocentre Magendie, 33000 Bordeaux, France
| | - Maïté M Moreau
- INSERM, Neurocentre Magendie, U1215, 33000 Bordeaux, France; Université Bordeaux, Neurocentre Magendie, 33000 Bordeaux, France
| | - Steve Dos Santos Carvalho
- INSERM, Neurocentre Magendie, U1215, 33000 Bordeaux, France; Université Bordeaux, Neurocentre Magendie, 33000 Bordeaux, France
| | - Gael Barthet
- CNRS, IINS, UMR 5297, 33000 Bordeaux, France; Université Bordeaux, IINS, 33000 Bordeaux, France
| | - Claudia Racca
- Biosciences Institute, Newcastle University, Medical School, Newcastle upon Tyne, NE2 4HH, UK
| | - Mehdi Bhouri
- INSERM, Neurocentre Magendie, U1215, 33000 Bordeaux, France; Université Bordeaux, Neurocentre Magendie, 33000 Bordeaux, France
| | - Anne Quiedeville
- INSERM, Neurocentre Magendie, U1215, 33000 Bordeaux, France; Université Bordeaux, Neurocentre Magendie, 33000 Bordeaux, France
| | - Maurice Garret
- CNRS, INCIA, 33000 Bordeaux, France; Université Bordeaux, INCIA, 30000 Bordeaux, France
| | - Bénédicte Atchama
- INSERM, Neurocentre Magendie, U1215, 33000 Bordeaux, France; Université Bordeaux, Neurocentre Magendie, 33000 Bordeaux, France
| | - Alice Shaam Al Abed
- INSERM, Neurocentre Magendie, U1215, 33000 Bordeaux, France; Université Bordeaux, Neurocentre Magendie, 33000 Bordeaux, France
| | - Christelle Guette
- INSERM, Neurocentre Magendie, U1215, 33000 Bordeaux, France; Université Bordeaux, Neurocentre Magendie, 33000 Bordeaux, France
| | - Deborah J Henderson
- Biosciences Institute, Newcastle University, Centre for Life, Newcastle upon Tyne, NE1 4EP, UK
| | - Aline Desmedt
- INSERM, Neurocentre Magendie, U1215, 33000 Bordeaux, France; Université Bordeaux, Neurocentre Magendie, 33000 Bordeaux, France
| | - Christophe Mulle
- CNRS, IINS, UMR 5297, 33000 Bordeaux, France; Université Bordeaux, IINS, 33000 Bordeaux, France
| | - Aline Marighetto
- INSERM, Neurocentre Magendie, U1215, 33000 Bordeaux, France; Université Bordeaux, Neurocentre Magendie, 33000 Bordeaux, France
| | - Mireille Montcouquiol
- INSERM, Neurocentre Magendie, U1215, 33000 Bordeaux, France; Université Bordeaux, Neurocentre Magendie, 33000 Bordeaux, France.
| | - Nathalie Sans
- INSERM, Neurocentre Magendie, U1215, 33000 Bordeaux, France; Université Bordeaux, Neurocentre Magendie, 33000 Bordeaux, France.
| |
Collapse
|
10
|
Neuronal fibroblast growth factor 22 signaling during development, but not in adults, is involved in anhedonia. Neuroreport 2021; 31:125-130. [PMID: 31895747 DOI: 10.1097/wnr.0000000000001399] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Growth factor signaling in the brain is implicated in many neuropsychiatric disorders, including depression, autism, and epilepsy. Fibroblast growth factor 22 is a growth factor that regulates excitatory synapse development and neurogenesis in the brain. We have previously shown that adult mice in which fibroblast growth factor 22 is constitutively inactivated in all cells throughout life (fibroblast growth factor 22-null mice) show anhedonia, a core feature of depression in humans, suggesting that fibroblast growth factor 22 signaling contributes to the regulation of affective behavior. Here we asked (1) whether inactivation of fibroblast growth factor 22 specifically in neurons is sufficient to induce anhedonia in mice and (2) whether fibroblast growth factor 22 signaling is important during development or in adults for the regulation of affective behavior. To address these questions, we performed the sucrose preference test, which is used as an indicator of anhedonia, with neuron-specific conditional fibroblast growth factor 22 knockout mice, in which fibroblast growth factor 22 is inactivated in neurons at birth (neonatal-fibroblast growth factor 22-knockout mice) or in adults (adult-fibroblast growth factor 22-knockout mice). We found that neonatal-fibroblast growth factor 22-knockout mice show anhedonia (decreased preference for sucrose), while adult-fibroblast growth factor 22-knockout mice do not. Therefore, neuronal fibroblast growth factor 22 signaling is critical during development, and not in adults, for the regulation of affective behavior. Our work also implies that defects in growth factor-dependent synapse development, neurogenesis, or both may underlie depression of a developmental origin.
Collapse
|
11
|
Kharouf Q, Phillips AM, Bleakley LE, Morrisroe E, Oyrer J, Jia L, Ludwig A, Jin L, Nicolazzo JA, Cerbai E, Romanelli MN, Petrou S, Reid CA. The hyperpolarization-activated cyclic nucleotide-gated 4 channel as a potential anti-seizure drug target. Br J Pharmacol 2020; 177:3712-3729. [PMID: 32364262 DOI: 10.1111/bph.15088] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 03/24/2020] [Accepted: 04/16/2020] [Indexed: 01/03/2023] Open
Abstract
BACKGROUND AND PURPOSE Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels are encoded by four genes (HCN1-4) with distinct biophysical properties and functions within the brain. HCN4 channels activate slowly at robust hyperpolarizing potentials, making them more likely to be engaged during hyperexcitable neuronal network activity seen during seizures. HCN4 channels are also highly expressed in thalamic nuclei, a brain region implicated in seizure generalization. Here, we assessed the utility of targeting the HCN4 channel as an anti-seizure strategy using pharmacological and genetic approaches. EXPERIMENTAL APPROACH The impact of reducing HCN4 channel function on seizure susceptibility and neuronal network excitability was studied using an HCN4 channel preferring blocker (EC18) and a conditional brain specific HCN4 knockout mouse model. KEY RESULTS EC18 (10 mg·kg-1 ) and brain-specific HCN4 channel knockout reduced seizure susceptibility and proconvulsant-mediated cortical spiking recorded using electrocorticography, with minimal effects on other mouse behaviours. EC18 (10 μM) decreased neuronal network bursting in mouse cortical cultures. Importantly, EC18 was not protective against proconvulsant-mediated seizures in the conditional HCN4 channel knockout mouse and did not reduce bursting behaviour in AAV-HCN4 shRNA infected mouse cortical cultures. CONCLUSIONS AND IMPLICATIONS These data suggest the HCN4 channel as a potential pharmacologically relevant target for anti-seizure drugs that is likely to have a low side-effect liability in the CNS.
Collapse
Affiliation(s)
- Qays Kharouf
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria, Australia
| | - A Marie Phillips
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria, Australia.,School of Biosciences, University of Melbourne, Parkville, Victoria, Australia
| | - Lauren E Bleakley
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria, Australia
| | - Emma Morrisroe
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria, Australia
| | - Julia Oyrer
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria, Australia
| | - Linghan Jia
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria, Australia
| | - Andreas Ludwig
- Institut für Experimentelle und Klinische Pharmakologie und Toxikologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Liang Jin
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia
| | - Joseph A Nicolazzo
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia
| | - Elisabetta Cerbai
- Department of Neurosciences, Psychology, Drug Research and Child Health, (NEUROFARBA), University of Florence, Florence, Italy
| | - M Novella Romanelli
- Department of Neurosciences, Psychology, Drug Research and Child Health, (NEUROFARBA), University of Florence, Florence, Italy
| | - Steven Petrou
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria, Australia
| | - Christopher A Reid
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Victoria, Australia
| |
Collapse
|
12
|
Shi L, Bergson CM. Neuregulin 1: an intriguing therapeutic target for neurodevelopmental disorders. Transl Psychiatry 2020; 10:190. [PMID: 32546684 PMCID: PMC7297728 DOI: 10.1038/s41398-020-00868-5] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 05/14/2020] [Accepted: 05/22/2020] [Indexed: 12/14/2022] Open
Abstract
Neurodevelopmental psychiatric disorders including schizophrenia (Sz) and attention deficit hyperactivity disorder (ADHD) are chronic mental illnesses, which place costly and painful burdens on patients, their families and society. In recent years, the epidermal growth factor (EGF) family member Neuregulin 1 (NRG1) and one of its receptors, ErbB4, have received considerable attention due to their regulation of inhibitory local neural circuit mechanisms important for information processing, attention, and cognitive flexibility. Here we examine an emerging body of work indicating that either decreasing NRG1-ErbB4 signaling in fast-spiking parvalbumin positive (PV+) interneurons or increasing it in vasoactive intestinal peptide positive (VIP+) interneurons could reactivate cortical plasticity, potentially making it a future target for gene therapy in adults with neurodevelopmental disorders. We propose preclinical studies to explore this model in prefrontal cortex (PFC), but also review the many challenges in pursuing cell type and brain-region-specific therapeutic approaches for the NRG1 system.
Collapse
Affiliation(s)
- Liang Shi
- grid.410427.40000 0001 2284 9329Department of Pharmacology and Toxicology, Medical College of Georgia at Augusta University, 1460 Laney Walker Boulevard, Augusta, GA 30912 USA ,grid.189967.80000 0001 0941 6502Present Address: Department of Cell Biology, Emory University School of Medicine, Atlanta, GA USA
| | - Clare M. Bergson
- grid.410427.40000 0001 2284 9329Department of Pharmacology and Toxicology, Medical College of Georgia at Augusta University, 1460 Laney Walker Boulevard, Augusta, GA 30912 USA
| |
Collapse
|
13
|
Santosa SM, Guo K, Yamakawa M, Ivakhnitskaia E, Chawla N, Nguyen T, Han KY, Ema M, Rosenblatt MI, Chang JH, Azar DT. Simultaneous fluorescence imaging of distinct nerve and blood vessel patterns in dual Thy1-YFP and Flt1-DsRed transgenic mice. Angiogenesis 2020; 23:459-477. [PMID: 32372335 DOI: 10.1007/s10456-020-09724-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Accepted: 04/23/2020] [Indexed: 02/08/2023]
Abstract
Blood vessels and nerve tissues are critical to the development and functionality of many vital organs. However, little is currently known about their interdependency during development and after injury. In this study, dual fluorescence transgenic reporter mice were utilized to observe blood vessels and nervous tissues in organs postnatally. Thy1-YFP and Flt1-DsRed (TYFD) mice were interbred to achieve dual fluorescence in the offspring, with Thy1-YFP yellow fluorescence expressed primarily in nerves, and Flt1-DsRed fluorescence expressed selectively in blood vessels. Using this dual fluorescent mouse strain, we were able to visualize the networks of nervous and vascular tissue simultaneously in various organ systems both in the physiological state and after injury. Using ex vivo high-resolution imaging in this dual fluorescent strain, we characterized the organizational patterns of both nervous and vascular systems in a diverse set of organs and tissues. In the cornea, we also observed the dynamic patterns of nerve and blood vessel networks following epithelial debridement injury. These findings highlight the versatility of this dual fluorescent strain for characterizing the relationship between nerve and blood vessel growth and organization.
Collapse
Affiliation(s)
- Samuel M Santosa
- Department of Ophthalmology and Visual Sciences, Illinois Eye and Ear Infirmary, College of Medicine, University of Illinois at Chicago, Chicago, IL, USA
| | - Kai Guo
- Department of Ophthalmology and Visual Sciences, Illinois Eye and Ear Infirmary, College of Medicine, University of Illinois at Chicago, Chicago, IL, USA
| | - Michael Yamakawa
- Department of Ophthalmology and Visual Sciences, Illinois Eye and Ear Infirmary, College of Medicine, University of Illinois at Chicago, Chicago, IL, USA
| | - Evguenia Ivakhnitskaia
- Department of Ophthalmology and Visual Sciences, Illinois Eye and Ear Infirmary, College of Medicine, University of Illinois at Chicago, Chicago, IL, USA
| | - Neeraj Chawla
- Department of Ophthalmology and Visual Sciences, Illinois Eye and Ear Infirmary, College of Medicine, University of Illinois at Chicago, Chicago, IL, USA
| | - Tara Nguyen
- Department of Ophthalmology and Visual Sciences, Illinois Eye and Ear Infirmary, College of Medicine, University of Illinois at Chicago, Chicago, IL, USA
| | - Kyu-Yeon Han
- Department of Ophthalmology and Visual Sciences, Illinois Eye and Ear Infirmary, College of Medicine, University of Illinois at Chicago, Chicago, IL, USA
| | - Masatsugu Ema
- Department of Stem Cells and Human Disease Models, Shiga University of Medical Science, Seta, Tsukinowa-cho, Otsu, Shiga, Japan
| | - Mark I Rosenblatt
- Department of Ophthalmology and Visual Sciences, Illinois Eye and Ear Infirmary, College of Medicine, University of Illinois at Chicago, Chicago, IL, USA
| | - Jin-Hong Chang
- Department of Ophthalmology and Visual Sciences, Illinois Eye and Ear Infirmary, College of Medicine, University of Illinois at Chicago, Chicago, IL, USA.
| | - Dimitri T Azar
- Department of Ophthalmology and Visual Sciences, Illinois Eye and Ear Infirmary, College of Medicine, University of Illinois at Chicago, Chicago, IL, USA.
| |
Collapse
|
14
|
Abstract
Autophagy is a lysosomal degradation pathway that plays an essential role in neuronal homeostasis and is perturbed in many neurological diseases. Transcriptional downregulation of fat was previously observed in a Drosophila model of the polyglutamine disease Dentatorubral-pallidoluysian atrophy (DRPLA) and this was shown to be partially responsible for autophagy defects and neurodegeneration. However, it is still unclear whether a downregulation of mammalian Fat orthologues is associated with neurodegeneration in mice. We hereby show that all four Fat orthologues are transcriptionally downregulated in the cerebellum in a mouse model of DRPLA. To elucidate the possible roles of single Fat genes, this study concentrates on Fat3. This fat homologue is shown to be the most widely expressed in the brain. Conditional knockout (KO) of Fat3 in brains of adult mice was attempted using the inducible Thy1Cre(ERT2) SLICK H line. Behavioral and biochemical analysis revealed that mice with conditional KO of Fat3 in the brain display no abnormalities. This may be ascribed either to the limited efficiency of the KO strategy pursued or to the lack of effect of Fat3 KO on autophagy.
Collapse
|
15
|
Scott J, Thakar S, Mao Y, Qin H, Hejran H, Lee SY, Yu T, Klezovitch O, Cheng H, Mu Y, Ghosh S, Vasioukhin V, Zou Y. Apical-Basal Polarity Signaling Components, Lgl1 and aPKCs, Control Glutamatergic Synapse Number and Function. iScience 2019; 20:25-41. [PMID: 31546104 PMCID: PMC6817635 DOI: 10.1016/j.isci.2019.09.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Revised: 08/25/2019] [Accepted: 09/04/2019] [Indexed: 12/17/2022] Open
Abstract
Normal synapse formation is fundamental to brain function. We show here that an apical-basal polarity (A-BP) protein, Lgl1, is present in the postsynaptic density and negatively regulates glutamatergic synapse numbers by antagonizing the atypical protein kinase Cs (aPKCs). A planar cell polarity protein, Vangl2, which inhibits synapse formation, was decreased in synaptosome fractions of cultured cortical neurons from Lgl1 knockout embryos. Conditional knockout of Lgl1 in pyramidal neurons led to reduction of AMPA/NMDA ratio and impaired plasticity. Lgl1 is frequently deleted in Smith-Magenis syndrome (SMS). Lgl1 conditional knockout led to increased locomotion, impaired novel object recognition and social interaction. Lgl1+/- animals also showed increased synapse numbers, defects in open field and social interaction, as well as stereotyped repetitive behavior. Social interaction in Lgl1+/- could be rescued by NMDA antagonists. Our findings reveal a role of apical-basal polarity proteins in glutamatergic synapse development and function and also suggest a potential treatment for SMS patients with Lgl1 deletion.
Collapse
Affiliation(s)
- John Scott
- Neurobiology Section, Biological Sciences Division, University of California, San Diego, La Jolla, CA 92093, USA
| | - Sonal Thakar
- Neurobiology Section, Biological Sciences Division, University of California, San Diego, La Jolla, CA 92093, USA
| | - Ye Mao
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Huaping Qin
- Neurobiology Section, Biological Sciences Division, University of California, San Diego, La Jolla, CA 92093, USA
| | - Helen Hejran
- Neurobiology Section, Biological Sciences Division, University of California, San Diego, La Jolla, CA 92093, USA
| | - Su-Yee Lee
- Neurobiology Section, Biological Sciences Division, University of California, San Diego, La Jolla, CA 92093, USA
| | - Ting Yu
- Neurobiology Section, Biological Sciences Division, University of California, San Diego, La Jolla, CA 92093, USA
| | - Olga Klezovitch
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Hongqiang Cheng
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Yongxin Mu
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Sourav Ghosh
- Department of Neurology, Yale University, New Haven, CT 06511, USA
| | - Valeri Vasioukhin
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Yimin Zou
- Neurobiology Section, Biological Sciences Division, University of California, San Diego, La Jolla, CA 92093, USA.
| |
Collapse
|
16
|
O'Malley HA, Hull JM, Clawson BC, Chen C, Owens-Fiestan G, Jameson MB, Aton SJ, Parent JM, Isom LL. Scn1b deletion in adult mice results in seizures and SUDEP. Ann Clin Transl Neurol 2019; 6:1121-1126. [PMID: 31211177 PMCID: PMC6562025 DOI: 10.1002/acn3.785] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Revised: 04/05/2019] [Accepted: 04/08/2019] [Indexed: 01/01/2023] Open
Abstract
Pathogenic loss‐of‐function variants in SCN1B are linked to Dravet syndrome (DS). Previous work suggested that neuronal pathfinding defects underlie epileptogenesis and SUDEP in the Scn1b null mouse model of DS. We tested this hypothesis by inducing Scn1b deletion in adult mice that had developed normally. Epilepsy and SUDEP, which occur by postnatal day 21 in Scn1b null animals, were observed within 20 days of induced Scn1b deletion in adult mice, suggesting that epileptogenesis in SCN1B‐DS does not result from defective brain development. Thus, the developmental brain defects observed previously in Scn1b null mice may model other co‐morbidities of DS.
Collapse
Affiliation(s)
- Heather A O'Malley
- Department of Pharmacology University of Michigan Ann Arbor Michigan 48109
| | - Jacob M Hull
- Neuroscience Graduate Program University of Michigan Ann Arbor Michigan 48109
| | - Brittany C Clawson
- Department of Molecular, Cellular, and Developmental Biology University of Michigan Ann Arbor Michigan 48109
| | - Chunling Chen
- Department of Pharmacology University of Michigan Ann Arbor Michigan 48109
| | - Gic Owens-Fiestan
- Department of Neurology University of Michigan Ann Arbor Michigan 48109
| | - Margaret B Jameson
- Department of Neurology University of Michigan Ann Arbor Michigan 48109.,Present address: Department of Neuroscience University of Wisconsin Madison Wisconsin
| | - Sara J Aton
- Neuroscience Graduate Program University of Michigan Ann Arbor Michigan 48109.,Department of Molecular, Cellular, and Developmental Biology University of Michigan Ann Arbor Michigan 48109
| | - Jack M Parent
- Neuroscience Graduate Program University of Michigan Ann Arbor Michigan 48109.,Department of Neurology University of Michigan Ann Arbor Michigan 48109
| | - Lori L Isom
- Department of Pharmacology University of Michigan Ann Arbor Michigan 48109.,Neuroscience Graduate Program University of Michigan Ann Arbor Michigan 48109.,Department of Neurology University of Michigan Ann Arbor Michigan 48109
| |
Collapse
|
17
|
Stone S, Yue Y, Stanojlovic M, Wu S, Karsenty G, Lin W. Neuron-specific PERK inactivation exacerbates neurodegeneration during experimental autoimmune encephalomyelitis. JCI Insight 2019; 4:124232. [PMID: 30674717 DOI: 10.1172/jci.insight.124232] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Accepted: 12/05/2018] [Indexed: 12/14/2022] Open
Abstract
Multiple sclerosis (MS) and its animal model, experimental autoimmune encephalomyelitis (EAE), are chronic inflammatory demyelinating and neurodegenerative diseases of the CNS. Although neurodegeneration is the major contributor to chronic disability in MS, mechanisms governing the viability of axons and neurons in MS and EAE remain elusive. Data indicate that activation of pancreatic endoplasmic reticulum kinase (PERK) influences, positively or negatively, neuron and axon viability in various neurodegenerative diseases through induction of ATF4. In this study, we demonstrate that the PERK pathway was activated in neurons during EAE. We found that neuron-specific PERK inactivation impaired EAE resolution and exacerbated EAE-induced axon degeneration, neuron loss, and demyelination. Surprisingly, neuron-specific ATF4 inactivation did not alter EAE disease course or EAE-induced axon degeneration, neuron loss, and demyelination. These results suggest that PERK activation in neurons protects axons and neurons against inflammation in MS and EAE through ATF4-independent mechanisms.
Collapse
Affiliation(s)
- Sarrabeth Stone
- Department of Neuroscience and.,Institute for Translational Neuroscience, University of Minnesota, Minneapolis, Minnesota, USA
| | - Yuan Yue
- Department of Neuroscience and.,Institute for Translational Neuroscience, University of Minnesota, Minneapolis, Minnesota, USA
| | - Milos Stanojlovic
- Department of Neuroscience and.,Institute for Translational Neuroscience, University of Minnesota, Minneapolis, Minnesota, USA
| | - Shuangchan Wu
- Department of Neuroscience and.,Institute for Translational Neuroscience, University of Minnesota, Minneapolis, Minnesota, USA
| | - Gerard Karsenty
- Department of Genetics and Development, Columbia University College of Physicians and Surgeons, New York, New York, USA
| | - Wensheng Lin
- Department of Neuroscience and.,Institute for Translational Neuroscience, University of Minnesota, Minneapolis, Minnesota, USA
| |
Collapse
|
18
|
Simultaneous Ablation of Neuronal Neurofascin and Ankyrin G in Young and Adult Mice Reveals Age-Dependent Increase in Nodal Stability in Myelinated Axons and Differential Effects on the Lifespan. eNeuro 2018; 5:eN-NWR-0138-18. [PMID: 29963618 PMCID: PMC6021167 DOI: 10.1523/eneuro.0138-18.2018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2018] [Revised: 06/07/2018] [Accepted: 06/07/2018] [Indexed: 12/25/2022] Open
Abstract
Nodes of Ranvier are unique regions where voltage-gated sodium channels are highly enriched to drive saltatory conduction. Genetic ablations in adult mice with loss of specific nodal proteins causes slow but progressive nodal deterioration associated with decreased nerve conduction and axonopathy. What has remained unaddressed is whether loss of nodal proteins at different time points in postnatal life follows similar timelines of nodal disorganization. Here we utilized simultaneous ablation of Neurofascin (NF186) and Ankyrin G (AnkG) in mice of both sexes at three specific time points. We report that concurrent ablation of these core nodal components at postnatal day 13 (P13) leads to accelerated nodal destabilization in comparison with P23, and this disorganization is even slower when ablated at P93. Ablation of NF186 with AnkG at P13 reduced the half-life of NF186 to 15 days compared to 1 month at P23, which increased to 2 months at P93, indicating increasing nodal stability. The half-life of AnkG at the nodes also increased with age but showed enhanced disappearance from the node in the absence of NF186, with a half-life of 3 days at P13 ablation. The nodal disorganization occurred in a sequential manner, with AnkG disappearing first from the nodal areas irrespective of the timing of ablation, and led to decreased nerve conduction and affected axonal health. Together, our studies reveal that nodes of Ranvier in myelinated axons continue to become more stable with age and suggest that nodal disorganization in adult human demyelinating disorders occurs slowly until neurological symptoms become evident.
Collapse
|
19
|
Jaiswal PB, Mistretta OC, Ward PJ, English AW. Chemogenetic Enhancement of Axon Regeneration Following Peripheral Nerve Injury in the SLICK-A Mouse. Brain Sci 2018; 8:brainsci8050093. [PMID: 29786639 PMCID: PMC5977084 DOI: 10.3390/brainsci8050093] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Revised: 05/17/2018] [Accepted: 05/18/2018] [Indexed: 11/16/2022] Open
Abstract
The effects of chemogenetics on axon regeneration following peripheral nerve transection and repair were studied in mice expressing a Cre-dependent excitatory designer receptor exclusively activated by designer drugs (DREADD) and Cre-recombinase/yellow fluorescent protein (YFP) in a subset of motor and sensory neurons and cortical motoneurons (SLICK-A). Sciatic nerves were cut and repaired and mice were treated either once, at the time of injury, or five days per week for two weeks with clozapine N-oxide (CNO) (1 mg/kg, i.p.), or were untreated controls. Two weeks after injury, the lengths of YFP+ axon profiles were measured in nerves harvested from euthanized animals. Compared to untreated controls, regenerating axon lengths were not significantly longer in mice treated only once with CNO, but they were more than three times longer in mice receiving CNO repeatedly. Based on results of retrograde labeling experiments, axons of more sensory and motor neurons had regenerated successfully in mice receiving multiple CNO treatments than animals receiving only one treatment or no treatments. The increase in numbers of labeled sensory, but not motor neurons could be accounted for by increases in the proportion of retrogradely labeled neurons also expressing the DREADD. Chemogenetic increases in neuronal excitability represent a potent and innovative treatment to promote peripheral nerve regeneration.
Collapse
Affiliation(s)
- Poonam B Jaiswal
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, USA.
| | - Olivia C Mistretta
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, USA.
| | - Patricia J Ward
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, USA.
| | - Arthur W English
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, USA.
| |
Collapse
|
20
|
Nichols M, Pavlov EV, Robertson GS. Tamoxifen-induced knockdown of the mitochondrial calcium uniporter in Thy1-expressing neurons protects mice from hypoxic/ischemic brain injury. Cell Death Dis 2018; 9:606. [PMID: 29789575 PMCID: PMC5964108 DOI: 10.1038/s41419-018-0607-9] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Revised: 03/14/2018] [Accepted: 03/29/2018] [Indexed: 12/24/2022]
Abstract
The mitochondrial calcium uniporter (MCU) mediates high-capacity mitochondrial calcium uptake that stimulates energy production. However, excessive MCU activity can cause ischemic heart injury. To examine if the MCU is also involved in hypoxic/ischemic (HI) brain injury, we have generated conditional MCU knockout mice by tamoxifen (TMX) administration to adult MCU-floxed (MCUfl/fl) mice expressing a construct encoding Thy1-cre/ERT2-eYFP. Relative to TMX/Thy1-cre/ERT2-eYFP controls, HI-induced sensorimotor deficits, forebrain neuron loss and mitochondrial damage were decreased for conditional MCU knockout mice. MCU knockdown by siRNA-induced silencing in cortical neuron cultures also reduced cell death and mitochondrial respiratory deficits following oxygen-glucose deprivation. Furthermore, MCU silencing did not produce metabolic abnormalities in cortical neurons observed previously for global MCU nulls that increased reliance on glycolysis for energy production. Based on these findings, we propose that brain-penetrant MCU inhibitors have strong potential to be well-tolerated and highly-efficacious neuroprotectants for the acute management of ischemic stroke.
Collapse
Affiliation(s)
- Matthew Nichols
- Department of Pharmacology, Brain Repair Centre, Faculty of Medicine, 2nd Floor, Life Sciences Research Institute, Dalhousie University, 1348 Summer Street, P.O. Box 15000, Halifax, Nova Scotia, Canada, B3H 4R2
| | - Evgeny V Pavlov
- Department of Basic Sciences, College of Dentistry, New York University, 345 East 24th Street, New York, NY, 10010, USA
| | - George S Robertson
- Department of Pharmacology, Brain Repair Centre, Faculty of Medicine, 2nd Floor, Life Sciences Research Institute, Dalhousie University, 1348 Summer Street, P.O. Box 15000, Halifax, Nova Scotia, Canada, B3H 4R2. .,Department of Psychiatry, QEII Health Sciences Centre, 5909 Veterans' Memorial Lane, 8th floor, Abbie J. Lane Memorial Building, Halifax, NS, B3H 2E2, Canada.
| |
Collapse
|
21
|
Koronowski KB, Khoury N, Saul I, Loris ZB, Cohan CH, Stradecki-Cohan HM, Dave KR, Young JI, Perez-Pinzon MA. Neuronal SIRT1 (Silent Information Regulator 2 Homologue 1) Regulates Glycolysis and Mediates Resveratrol-Induced Ischemic Tolerance. Stroke 2017; 48:3117-3125. [PMID: 29018134 PMCID: PMC5654689 DOI: 10.1161/strokeaha.117.018562] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Revised: 09/06/2017] [Accepted: 09/13/2017] [Indexed: 12/13/2022]
Abstract
BACKGROUND AND PURPOSE Resveratrol, at least in part via SIRT1 (silent information regulator 2 homologue 1) activation, protects against cerebral ischemia when administered 2 days before injury. However, it remains unclear if SIRT1 activation must occur, and in which brain cell types, for the induction of neuroprotection. We hypothesized that neuronal SIRT1 is essential for resveratrol-induced ischemic tolerance and sought to characterize the metabolic pathways regulated by neuronal Sirt1 at the cellular level in the brain. METHODS We assessed infarct size and functional outcome after transient 60 minute middle cerebral artery occlusion in control and inducible, neuronal-specific SIRT1 knockout mice. Nontargeted primary metabolomics analysis identified putative SIRT1-regulated pathways in brain. Glycolytic function was evaluated in acute brain slices from adult mice and primary neuronal-enriched cultures under ischemic penumbra-like conditions. RESULTS Resveratrol-induced neuroprotection from stroke was lost in neuronal Sirt1 knockout mice. Metabolomics analysis revealed alterations in glucose metabolism on deletion of neuronal Sirt1, accompanied by transcriptional changes in glucose metabolism machinery. Furthermore, glycolytic ATP production was impaired in acute brain slices from neuronal Sirt1 knockout mice. Conversely, resveratrol increased glycolytic rate in a SIRT1-dependent manner and under ischemic penumbra-like conditions in vitro. CONCLUSIONS Our data demonstrate that resveratrol requires neuronal SIRT1 to elicit ischemic tolerance and identify a novel role for SIRT1 in the regulation of glycolytic function in brain. Identification of robust neuroprotective mechanisms that underlie ischemia tolerance and the metabolic adaptations mediated by SIRT1 in brain are crucial for the translation of therapies in cerebral ischemia and other neurological disorders.
Collapse
Affiliation(s)
- Kevin B Koronowski
- From the Cerebral Vascular Disease Research Laboratories (K.B.K., N.K., I.S., C.H.C., H.M.S.-C., K.R.D., M.A.P.-P.), Department of Neurology (K.B.K., N.K., I.S., C.H.C., H.M.S.-C., K.R.D., M.A.P.-P.), The Miami Project to Cure Paralysis (Z.B.L.), Department of Neurological Surgery (Z.B.L.), John P. Hussman Institute for Human Genomics (J.I.Y.) and Department of Human Genetics (J.I.Y.), University of Miami Leonard M. Miller School of Medicine, FL
| | - Nathalie Khoury
- From the Cerebral Vascular Disease Research Laboratories (K.B.K., N.K., I.S., C.H.C., H.M.S.-C., K.R.D., M.A.P.-P.), Department of Neurology (K.B.K., N.K., I.S., C.H.C., H.M.S.-C., K.R.D., M.A.P.-P.), The Miami Project to Cure Paralysis (Z.B.L.), Department of Neurological Surgery (Z.B.L.), John P. Hussman Institute for Human Genomics (J.I.Y.) and Department of Human Genetics (J.I.Y.), University of Miami Leonard M. Miller School of Medicine, FL
| | - Isabel Saul
- From the Cerebral Vascular Disease Research Laboratories (K.B.K., N.K., I.S., C.H.C., H.M.S.-C., K.R.D., M.A.P.-P.), Department of Neurology (K.B.K., N.K., I.S., C.H.C., H.M.S.-C., K.R.D., M.A.P.-P.), The Miami Project to Cure Paralysis (Z.B.L.), Department of Neurological Surgery (Z.B.L.), John P. Hussman Institute for Human Genomics (J.I.Y.) and Department of Human Genetics (J.I.Y.), University of Miami Leonard M. Miller School of Medicine, FL
| | - Zachary B Loris
- From the Cerebral Vascular Disease Research Laboratories (K.B.K., N.K., I.S., C.H.C., H.M.S.-C., K.R.D., M.A.P.-P.), Department of Neurology (K.B.K., N.K., I.S., C.H.C., H.M.S.-C., K.R.D., M.A.P.-P.), The Miami Project to Cure Paralysis (Z.B.L.), Department of Neurological Surgery (Z.B.L.), John P. Hussman Institute for Human Genomics (J.I.Y.) and Department of Human Genetics (J.I.Y.), University of Miami Leonard M. Miller School of Medicine, FL
| | - Charles H Cohan
- From the Cerebral Vascular Disease Research Laboratories (K.B.K., N.K., I.S., C.H.C., H.M.S.-C., K.R.D., M.A.P.-P.), Department of Neurology (K.B.K., N.K., I.S., C.H.C., H.M.S.-C., K.R.D., M.A.P.-P.), The Miami Project to Cure Paralysis (Z.B.L.), Department of Neurological Surgery (Z.B.L.), John P. Hussman Institute for Human Genomics (J.I.Y.) and Department of Human Genetics (J.I.Y.), University of Miami Leonard M. Miller School of Medicine, FL
| | - Holly M Stradecki-Cohan
- From the Cerebral Vascular Disease Research Laboratories (K.B.K., N.K., I.S., C.H.C., H.M.S.-C., K.R.D., M.A.P.-P.), Department of Neurology (K.B.K., N.K., I.S., C.H.C., H.M.S.-C., K.R.D., M.A.P.-P.), The Miami Project to Cure Paralysis (Z.B.L.), Department of Neurological Surgery (Z.B.L.), John P. Hussman Institute for Human Genomics (J.I.Y.) and Department of Human Genetics (J.I.Y.), University of Miami Leonard M. Miller School of Medicine, FL
| | - Kunjan R Dave
- From the Cerebral Vascular Disease Research Laboratories (K.B.K., N.K., I.S., C.H.C., H.M.S.-C., K.R.D., M.A.P.-P.), Department of Neurology (K.B.K., N.K., I.S., C.H.C., H.M.S.-C., K.R.D., M.A.P.-P.), The Miami Project to Cure Paralysis (Z.B.L.), Department of Neurological Surgery (Z.B.L.), John P. Hussman Institute for Human Genomics (J.I.Y.) and Department of Human Genetics (J.I.Y.), University of Miami Leonard M. Miller School of Medicine, FL
| | - Juan I Young
- From the Cerebral Vascular Disease Research Laboratories (K.B.K., N.K., I.S., C.H.C., H.M.S.-C., K.R.D., M.A.P.-P.), Department of Neurology (K.B.K., N.K., I.S., C.H.C., H.M.S.-C., K.R.D., M.A.P.-P.), The Miami Project to Cure Paralysis (Z.B.L.), Department of Neurological Surgery (Z.B.L.), John P. Hussman Institute for Human Genomics (J.I.Y.) and Department of Human Genetics (J.I.Y.), University of Miami Leonard M. Miller School of Medicine, FL
| | - Miguel A Perez-Pinzon
- From the Cerebral Vascular Disease Research Laboratories (K.B.K., N.K., I.S., C.H.C., H.M.S.-C., K.R.D., M.A.P.-P.), Department of Neurology (K.B.K., N.K., I.S., C.H.C., H.M.S.-C., K.R.D., M.A.P.-P.), The Miami Project to Cure Paralysis (Z.B.L.), Department of Neurological Surgery (Z.B.L.), John P. Hussman Institute for Human Genomics (J.I.Y.) and Department of Human Genetics (J.I.Y.), University of Miami Leonard M. Miller School of Medicine, FL.
| |
Collapse
|
22
|
Karabiyik C, Fernandes R, Figueiredo FR, Socodato R, Brakebusch C, Lambertsen KL, Relvas JB, Santos SD. Neuronal Rho GTPase Rac1 elimination confers neuroprotection in a mouse model of permanent ischemic stroke. Brain Pathol 2017; 28:569-580. [PMID: 28960571 DOI: 10.1111/bpa.12562] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Accepted: 09/21/2017] [Indexed: 01/08/2023] Open
Abstract
The Rho GTPase Rac1 is a multifunctional protein involved in distinct pathways ranging from development to pathology. The aim of the present study was to unravel the contribution of neuronal Rac1 in regulating the response to brain injury induced by permanent focal cerebral ischemia (pMCAO). Our results show that pMCAO significantly increased total Rac1 levels in wild type mice, mainly through rising nuclear Rac1, while a reduction in Rac1 activation was observed. Such changes preceded cell death induced by excitotoxic stress. Pharmacological inhibition of Rac1 in primary neuronal cortical cells prevented the increase in oxidative stress induced after overactivation of glutamate receptors. However, this was not sufficient to prevent the associated neuronal cell death. In contrast, RNAi-mediated knock down of Rac1 in primary cortical neurons prevented cell death elicited by glutamate excitotoxicity and decreased the activity of NADPH oxidase. To test whether in vivo down regulation of neuronal Rac1 was neuroprotective after pMCAO, we used tamoxifen-inducible neuron-specific conditional Rac1-knockout mice. We observed a significant 50% decrease in brain infarct volume of knockout mice and a concomitant increase in HIF-1α expression compared to littermate control mice, demonstrating that ablation of Rac1 in neurons is neuroprotective. Transmission electron microscopy performed in the ischemic brain showed that lysosomes in the infarct of Rac1- knockout mice were preserved at similar levels to those of non-infarcted tissue, while littermate mice displayed a decrease in the number of lysosomes, further corroborating the notion that Rac1 ablation in neurons is neuroprotective. Our results demonstrate that Rac1 plays important roles in the ischemic pathological cascade and that modulation of its levels is of therapeutic interest.
Collapse
Affiliation(s)
- Cansu Karabiyik
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal.,Glial Cell Biology, IBMC- Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal.,Department of Neurobiology Research, Institute of Molecular Medicine, University of Southern Denmark, Odense C, Denmark
| | - Rui Fernandes
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal.,HEMS, IBMC-Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
| | - Francisco Rosário Figueiredo
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal.,HEMS, IBMC-Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
| | - Renato Socodato
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal.,Glial Cell Biology, IBMC- Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
| | - Cord Brakebusch
- Biotech Research and Innovation Center, University of Copenhagen, Denmark
| | - Kate Lykke Lambertsen
- Department of Neurobiology Research, Institute of Molecular Medicine, University of Southern Denmark, Odense C, Denmark.,Department of Neurology, Odense University Hospital, Odence C, Denmark.,BRIDGE - Brain Research - Inter-Disciplinary Guided Excellence, Department of Clinical Research, University of Southern Denmark, Odense, Denmark
| | - João Bettencourt Relvas
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal.,Glial Cell Biology, IBMC- Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
| | - Sofia Duque Santos
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal.,Glial Cell Biology, IBMC- Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal.,INEB - Instituto de Engenharia Biomédica, Universidade do Porto, Porto, Portugal
| |
Collapse
|
23
|
Jardí F, Laurent MR, Dubois V, Khalil R, Deboel L, Schollaert D, Van Den Bosch L, Decallonne B, Carmeliet G, Claessens F, Vanderschueren D. A shortened tamoxifen induction scheme to induce CreER recombinase without side effects on the male mouse skeleton. Mol Cell Endocrinol 2017; 452:57-63. [PMID: 28504114 DOI: 10.1016/j.mce.2017.05.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Revised: 05/03/2017] [Accepted: 05/09/2017] [Indexed: 12/30/2022]
Abstract
The selective estrogen receptor modulator tamoxifen exerts estrogen agonistic or antagonistic actions on several tissues, including bone. The off-target effects of tamoxifen are one of the most widely recognized pitfalls of tamoxifen-inducible Cre recombinases (CreERs), potentially confounding the phenotypic findings. Still, the validation of tamoxifen induction schemes that minimize the side effects of the drug has not been addressed. Here, we compared the side effects on the skeleton and other androgen-responsive targets of a shortened tamoxifen regimen (2 doses of 190 mg/kg body weight by oral gavage) to a standard protocol (4 doses) and determined their efficiency in inducing CreER-mediated gene deletion. In addition, both a vehicle- and a 10-dose group, which served as a positive control for tamoxifen side effects, were also included. For this purpose, we generated male mice with a floxed androgen receptor (AR) and a neuron-specifically expressed CreER. Treatment with two doses of tamoxifen was the only regimen that did not diminish androgenic bioactivity, as assessed by both seminal vesicles and levator ani/bulbocavernosus muscle weights and serum testosterone concentrations. Similarly, trabecular and cortical femoral bone structure were dramatically altered by both the standard and high-dose protocols but not by the shortened version. Serum osteocalcin and bone-gene expression analyses confirmed the absence of effects on bone by 2 doses of tamoxifen. This protocol decreased AR mRNA levels efficiently and specifically in the nervous system. Thus, we optimized a protocol for tamoxifen-induced CreER gene deletion in mice without off-target effects on bone and male reproductive organs.
Collapse
Affiliation(s)
- Ferran Jardí
- Clinical and Experimental Endocrinology, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49 PO Box 902, 3000 Leuven, Belgium
| | - Michaël R Laurent
- Molecular Endocrinology Laboratory, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49 PO Box 901, 3000 Leuven, Belgium; Gerontology and Geriatrics, Department of Clinical and Experimental Medicine, KU Leuven, Herestraat 49 PO Box 7003, Leuven, Belgium
| | - Vanessa Dubois
- Molecular Endocrinology Laboratory, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49 PO Box 901, 3000 Leuven, Belgium; INSERM UMR1011, University of Lille and Institut Pasteur de Lille, Lille, France
| | - Rougin Khalil
- Clinical and Experimental Endocrinology, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49 PO Box 902, 3000 Leuven, Belgium
| | - Ludo Deboel
- Clinical and Experimental Endocrinology, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49 PO Box 902, 3000 Leuven, Belgium
| | - Dieter Schollaert
- Clinical and Experimental Endocrinology, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49 PO Box 902, 3000 Leuven, Belgium
| | - Ludo Van Den Bosch
- Laboratory of Neurobiology, VIB Center for Brain and Disease Research and KU Leuven, 3000 Leuven, Belgium
| | - Brigitte Decallonne
- Clinical and Experimental Endocrinology, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49 PO Box 902, 3000 Leuven, Belgium
| | - Geert Carmeliet
- Clinical and Experimental Endocrinology, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49 PO Box 902, 3000 Leuven, Belgium
| | - Frank Claessens
- Molecular Endocrinology Laboratory, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49 PO Box 901, 3000 Leuven, Belgium
| | - Dirk Vanderschueren
- Clinical and Experimental Endocrinology, Department of Cellular and Molecular Medicine, KU Leuven, Herestraat 49 PO Box 902, 3000 Leuven, Belgium.
| |
Collapse
|
24
|
Taylor AM, Saifetiarova J, Bhat MA. Postnatal Loss of Neuronal and Glial Neurofascins Differentially Affects Node of Ranvier Maintenance and Myelinated Axon Function. Front Cell Neurosci 2017; 11:11. [PMID: 28217083 PMCID: PMC5289982 DOI: 10.3389/fncel.2017.00011] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Accepted: 01/13/2017] [Indexed: 12/16/2022] Open
Abstract
Intricate molecular interactions between neurons and glial cells underlie the creation of unique domains that are essential for saltatory conduction of action potentials by myelinated axons. Previously, the cell surface adhesion molecule Neurofascin (Nfasc) has been shown to have a dual-role in the establishment of axonal domains from both the glial and neuronal interface. While the neuron-specific isoform of Neurofascin (NF186) is indispensable for clustering of voltage-gated sodium channels at nodes of Ranvier; the glial-specific isoform of Neurofascin (NF155) is required for myelinating glial cells to organize the paranodal domain. Although many studies have addressed the individual roles of NF155 and NF186 in assembling paranodes and nodes, respectively; critical questions about their roles in the maintenance and long-term health of the myelinated axons remain, which we aimed to address in these studies. Here using spatiotemporal ablation of Neurofascin in neurons alone or together with myelinating glia, we report that loss of NF186 individually from postnatal mice leads to progressive nodal destabilization and axonal degeneration. While individual ablation of paranodal NF155 does not disrupt nodes of Ranvier; loss of NF186 combined with NF155 causes more accelerated nodal destabilization than loss of NF186 alone, providing strong evidence regarding a supporting role for paranodes in nodal maintenance. In both cases of NF186 loss, myelinating axons show ultrastructural changes and degeneration. Our studies reveal that long-term maintenance of nodes and ultimately the health of axons is correlated with the stability of NF186 within the nodal complex and the presence of auxiliary paranodes.
Collapse
Affiliation(s)
- Anna M Taylor
- Department of Cellular and Integrative Physiology, Center for Biomedical Neuroscience, School of Medicine, University of Texas Health Science Center San Antonio, TX, USA
| | - Julia Saifetiarova
- Department of Cellular and Integrative Physiology, Center for Biomedical Neuroscience, School of Medicine, University of Texas Health Science Center San Antonio, TX, USA
| | - Manzoor A Bhat
- Department of Cellular and Integrative Physiology, Center for Biomedical Neuroscience, School of Medicine, University of Texas Health Science Center San Antonio, TX, USA
| |
Collapse
|
25
|
Thakar S, Wang L, Yu T, Ye M, Onishi K, Scott J, Qi J, Fernandes C, Han X, Yates JR, Berg DK, Zou Y. Evidence for opposing roles of Celsr3 and Vangl2 in glutamatergic synapse formation. Proc Natl Acad Sci U S A 2017; 114:E610-E618. [PMID: 28057866 PMCID: PMC5278468 DOI: 10.1073/pnas.1612062114] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
The signaling mechanisms that choreograph the assembly of the highly asymmetric pre- and postsynaptic structures are still poorly defined. Using synaptosome fractionation, immunostaining, and coimmunoprecipitation, we found that Celsr3 and Vangl2, core components of the planar cell polarity (PCP) pathway, are localized at developing glutamatergic synapses and interact with key synaptic proteins. Pyramidal neurons from the hippocampus of Celsr3 knockout mice exhibit loss of ∼50% of glutamatergic synapses, but not inhibitory synapses, in culture. Wnts are known regulators of synapse formation, and our data reveal that Wnt5a inhibits glutamatergic synapses formed via Celsr3. To avoid affecting earlier developmental processes, such as axon guidance, we conditionally knocked out Celsr3 in the hippocampus 1 week after birth. The CA1 neurons that lost Celsr3 also showed a loss of ∼50% of glutamatergic synapses in vivo without affecting the inhibitory synapses assessed by miniature excitatory postsynaptic current (mEPSC) and electron microscopy. These animals displayed deficits in hippocampus-dependent behaviors in adulthood, including spatial learning and memory and fear conditioning. In contrast to Celsr3 conditional knockouts, we found that the conditional knockout of Vangl2 in the hippocampus 1 week after birth led to a large increase in synaptic density, as evaluated by mEPSC frequency and spine density. PCP signaling is mediated by multiple core components with antagonizing functions. Our results document the opposing roles of Celsr3 and Vangl2 in glutamatergic synapse formation.
Collapse
Affiliation(s)
- Sonal Thakar
- Neurobiology Section, Biological Sciences Division, University of California, San Diego, La Jolla, CA 92093
| | - Liqing Wang
- Neurobiology Section, Biological Sciences Division, University of California, San Diego, La Jolla, CA 92093
| | - Ting Yu
- Neurobiology Section, Biological Sciences Division, University of California, San Diego, La Jolla, CA 92093
| | - Mao Ye
- Neurobiology Section, Biological Sciences Division, University of California, San Diego, La Jolla, CA 92093
| | - Keisuke Onishi
- Neurobiology Section, Biological Sciences Division, University of California, San Diego, La Jolla, CA 92093
| | - John Scott
- Neurobiology Section, Biological Sciences Division, University of California, San Diego, La Jolla, CA 92093
| | - Jiaxuan Qi
- Neurobiology Section, Biological Sciences Division, University of California, San Diego, La Jolla, CA 92093
| | - Catarina Fernandes
- Neurobiology Section, Biological Sciences Division, University of California, San Diego, La Jolla, CA 92093
| | - Xuemei Han
- Department of Chemical Physiology, The Scripps Research Institute, La Jolla, CA 92037
| | - John R Yates
- Department of Chemical Physiology, The Scripps Research Institute, La Jolla, CA 92037
| | - Darwin K Berg
- Neurobiology Section, Biological Sciences Division, University of California, San Diego, La Jolla, CA 92093
| | - Yimin Zou
- Neurobiology Section, Biological Sciences Division, University of California, San Diego, La Jolla, CA 92093;
| |
Collapse
|
26
|
Cho KI, Yoon D, Qiu S, Danziger Z, Grill WM, Wetsel WC, Ferreira PA. Loss of Ranbp2 in motoneurons causes disruption of nucleocytoplasmic and chemokine signaling, proteostasis of hnRNPH3 and Mmp28, and development of amyotrophic lateral sclerosis-like syndromes. Dis Model Mech 2017; 10:559-579. [PMID: 28100513 PMCID: PMC5451164 DOI: 10.1242/dmm.027730] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Accepted: 12/12/2016] [Indexed: 12/12/2022] Open
Abstract
The pathogenic drivers of sporadic and familial motor neuron disease (MND), such amyotrophic lateral sclerosis (ALS), are unknown. MND impairs the Ran GTPase cycle, which controls nucleocytoplasmic transport, ribostasis and proteostasis; however, cause-effect mechanisms of Ran GTPase modulators in motoneuron pathobiology have remained elusive. The cytosolic and peripheral nucleoporin Ranbp2 is a crucial regulator of the Ran GTPase cycle and of the proteostasis of neurological disease-prone substrates, but the roles of Ranbp2 in motoneuron biology and disease remain unknown. This study shows that conditional ablation of Ranbp2 in mouse Thy1 motoneurons causes ALS syndromes with hypoactivity followed by hindlimb paralysis, respiratory distress and, ultimately, death. These phenotypes are accompanied by: a decline in the nerve conduction velocity, free fatty acids and phophatidylcholine of the sciatic nerve; a reduction in the g-ratios of sciatic and phrenic nerves; and hypertrophy of motoneurons. Furthermore, Ranbp2 loss disrupts the nucleocytoplasmic partitioning of the import and export nuclear receptors importin β and exportin 1, respectively, Ran GTPase and histone deacetylase 4. Whole-transcriptome, proteomic and cellular analyses uncovered that the chemokine receptor Cxcr4, its antagonizing ligands Cxcl12 and Cxcl14, and effector, latent and activated Stat3 all undergo early autocrine and proteostatic deregulation, and intracellular sequestration and aggregation as a result of Ranbp2 loss in motoneurons. These effects were accompanied by paracrine and autocrine neuroglial deregulation of hnRNPH3 proteostasis in sciatic nerve and motoneurons, respectively, and post-transcriptional downregulation of metalloproteinase 28 in the sciatic nerve. Mechanistically, our results demonstrate that Ranbp2 controls nucleocytoplasmic, chemokine and metalloproteinase 28 signaling, and proteostasis of substrates that are crucial to motoneuronal homeostasis and whose impairments by loss of Ranbp2 drive ALS-like syndromes. Summary: Loss of Ranbp2 in spinal motoneurons drives ALS syndromes in mice and Ranbp2 functions in nucleocytoplasmic trafficking, proteostasis and chemokine signaling uncover novel therapeutic targets and mechanisms for motoneuron disease.
Collapse
Affiliation(s)
- Kyoung-In Cho
- Department of Ophthalmology, Duke University Medical Center, Durham, NC 27710, USA
| | - Dosuk Yoon
- Department of Ophthalmology, Duke University Medical Center, Durham, NC 27710, USA
| | - Sunny Qiu
- Department of Ophthalmology, Duke University Medical Center, Durham, NC 27710, USA
| | - Zachary Danziger
- Department of Biomedical Engineering, Duke University, Durham, NC 27710, USA
| | - Warren M Grill
- Department of Biomedical Engineering, Duke University, Durham, NC 27710, USA
| | - William C Wetsel
- Departments of Psychiatry and Behavioral Sciences, Cell Biology, and Neurobiology, Mouse Behavioral and Neuroendocrine Analysis Core Facility, Duke University Medical Center, Durham, NC 27710, USA
| | - Paulo A Ferreira
- Department of Ophthalmology, Duke University Medical Center, Durham, NC 27710, USA .,Department of Pathology, Duke University Medical Center, Durham, NC 27710, USA
| |
Collapse
|
27
|
Lu Q, Pan ZH. Immunohistochemical Procedures for Characterizing the Retinal Expression Patterns of Cre Driver Mouse Lines. Methods Mol Biol 2017; 1642:181-194. [PMID: 28815501 DOI: 10.1007/978-1-4939-7169-5_12] [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] [Indexed: 12/16/2023]
Abstract
The retina is a thin neural tissue sitting on the backside of the eye, composed of light-sensing cells, interneurons, and output ganglion neurons. The latter send electrical signals to higher visual centers in the brain. Transgenic mouse lines are becoming one of the most valuable mammalian animal models for the study of visual signal processing within the retina. Especially, the generation of Cre recombinase transgenic mouse lines provides a powerful tool for genetic manipulation. A key step for the utilization of transgenic lines is the characterization of their transgene expression patterns in the retina. Here we describe a standard protocol for characterizing the expression pattern of the Cre recombinase or fluorescent proteins in the retina with an immunohistochemical approach.
Collapse
Affiliation(s)
- Qi Lu
- Department of Anatomy and Cell Biology, Wayne State University School of Medicine, 540 E. Canfield Avenue, Detroit, MI, 48201, USA.
| | - Zhuo-Hua Pan
- Department of Anatomy and Cell Biology, Wayne State University School of Medicine, 540 E. Canfield Avenue, Detroit, MI, 48201, USA
- Department of Ophthalmology, Kresge Eye Institute, Wayne State University School of Medicine, Detroit, MI, USA
| |
Collapse
|
28
|
Lenihan JA, Saha O, Heimer-McGinn V, Cryan JF, Feng G, Young PW. Decreased Anxiety-Related Behaviour but Apparently Unperturbed NUMB Function in Ligand of NUMB Protein-X (LNX) 1/2 Double Knockout Mice. Mol Neurobiol 2016; 54:8090-8109. [DOI: 10.1007/s12035-016-0261-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Accepted: 10/25/2016] [Indexed: 10/20/2022]
|
29
|
Chen L, Hambright WS, Na R, Ran Q. Ablation of the Ferroptosis Inhibitor Glutathione Peroxidase 4 in Neurons Results in Rapid Motor Neuron Degeneration and Paralysis. J Biol Chem 2015; 290:28097-28106. [PMID: 26400084 PMCID: PMC4653669 DOI: 10.1074/jbc.m115.680090] [Citation(s) in RCA: 322] [Impact Index Per Article: 35.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Revised: 09/22/2015] [Indexed: 01/06/2023] Open
Abstract
Glutathione peroxidase 4 (GPX4), an antioxidant defense enzyme active in repairing oxidative damage to lipids, is a key inhibitor of ferroptosis, a non-apoptotic form of cell death involving lipid reactive oxygen species. Here we show that GPX4 is essential for motor neuron health and survival in vivo. Conditional ablation of Gpx4 in neurons of adult mice resulted in rapid onset and progression of paralysis and death. Pathological inspection revealed that the paralyzed mice had a dramatic degeneration of motor neurons in the spinal cord but had no overt neuron degeneration in the cerebral cortex. Consistent with the role of GPX4 as a ferroptosis inhibitor, spinal motor neuron degeneration induced by Gpx4 ablation exhibited features of ferroptosis, including no caspase-3 activation, no TUNEL staining, activation of ERKs, and elevated spinal inflammation. Supplementation with vitamin E, another inhibitor of ferroptosis, delayed the onset of paralysis and death induced by Gpx4 ablation. Also, lipid peroxidation and mitochondrial dysfunction appeared to be involved in ferroptosis of motor neurons induced by Gpx4 ablation. Taken together, the dramatic motor neuron degeneration and paralysis induced by Gpx4 ablation suggest that ferroptosis inhibition by GPX4 is essential for motor neuron health and survival in vivo.
Collapse
Affiliation(s)
- Liuji Chen
- Department of Cellular and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229
| | - William Sealy Hambright
- Department of Cellular and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229
| | - Ren Na
- Department of Cellular and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229
| | - Qitao Ran
- Department of Cellular and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229; Research Service, South Texas Veterans Health Care System, San Antonio, Texas 78229.
| |
Collapse
|
30
|
Breuss M, Morandell J, Nimpf S, Gstrein T, Lauwers M, Hochstoeger T, Braun A, Chan K, Sánchez Guajardo ER, Zhang L, Suplata M, Heinze KG, Elsayad K, Keays DA. The Expression of Tubb2b Undergoes a Developmental Transition in Murine Cortical Neurons. J Comp Neurol 2015; 523:2161-86. [PMID: 26105993 DOI: 10.1002/cne.23836] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Revised: 06/17/2015] [Accepted: 06/18/2015] [Indexed: 01/20/2023]
Abstract
The development of the mammalian brain requires the generation, migration, and differentiation of neurons, cellular processes that are dependent on a dynamic microtubule cytoskeleton. Mutations in tubulin genes, which encode for the structural subunits of microtubules, cause detrimental neurological disorders known as the tubulinopathies. The disease spectra associated with different tubulin genes are overlapping but distinct, an observation believed to reflect functional specification of this multigene family. Perturbation of the β-tubulin TUBB2B is known to cause polymicrogyria, pachygyria, microcephaly, and axon guidance defects. Here we provide a detailed analysis of the expression pattern of its murine homolog Tubb2b. The generation and characterization of BAC-transgenic eGFP reporter mouse lines has revealed that it is highly expressed in progenitors and postmitotic neurons during cortical development. This contrasts with the 8-week-old cortex, in which Tubb2b expression is restricted to macroglia, and expression is almost completely absent in mature neurons. This developmental transition in neurons is mirrored in the adult hippocampus and the cerebellum but is not a universal feature of Tubb2b; its expression persists in a population of postmitotic neurons in the 8-week-old retina. We propose that the dynamic spatial and temporal expression of Tubb2b reflects specific functional requirements of the microtubule cytoskeleton.
Collapse
Affiliation(s)
- Martin Breuss
- IMP-Research Institute of Molecular Pathology, Vienna Biocenter (VBC), Vienna, 1030, Austria
| | - Jasmin Morandell
- IMP-Research Institute of Molecular Pathology, Vienna Biocenter (VBC), Vienna, 1030, Austria
| | - Simon Nimpf
- IMP-Research Institute of Molecular Pathology, Vienna Biocenter (VBC), Vienna, 1030, Austria
| | - Thomas Gstrein
- IMP-Research Institute of Molecular Pathology, Vienna Biocenter (VBC), Vienna, 1030, Austria
| | - Mattias Lauwers
- IMP-Research Institute of Molecular Pathology, Vienna Biocenter (VBC), Vienna, 1030, Austria
| | - Tobias Hochstoeger
- IMP-Research Institute of Molecular Pathology, Vienna Biocenter (VBC), Vienna, 1030, Austria
| | - Andreas Braun
- IMP-Research Institute of Molecular Pathology, Vienna Biocenter (VBC), Vienna, 1030, Austria.,Centre for Genomic Regulation (CRG), 08003, Barcelona, Spain
| | - Kelvin Chan
- Medical Scientist Training Program, Stony Brook University Medical Center, Stony Brook, New York, 11794
| | | | - Lijuan Zhang
- Advanced Microscopy, Campus Science Support Facilities (CSF), Vienna, 1030, Austria
| | - Marek Suplata
- Rudolf Virchow Center, DFG-Research Center for Experimental Biomedicine of the University of Würzburg, Würzburg, 97080, Germany
| | - Katrin G Heinze
- Rudolf Virchow Center, DFG-Research Center for Experimental Biomedicine of the University of Würzburg, Würzburg, 97080, Germany
| | - Kareem Elsayad
- Advanced Microscopy, Campus Science Support Facilities (CSF), Vienna, 1030, Austria
| | - David A Keays
- IMP-Research Institute of Molecular Pathology, Vienna Biocenter (VBC), Vienna, 1030, Austria
| |
Collapse
|
31
|
Zhan X, Cao M, Yoo AS, Zhang Z, Chen L, Crabtree GR, Wu JI. Generation of BAF53b-Cre transgenic mice with pan-neuronal Cre activities. Genesis 2015; 53:440-8. [PMID: 26077106 DOI: 10.1002/dvg.22866] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Revised: 06/08/2015] [Accepted: 06/11/2015] [Indexed: 11/11/2022]
Abstract
Molecular and functional studies of genes in neurons in mouse models require neuron-specific Cre lines. The current available neuronal Cre transgenic or knock-in lines either result in expression in a subset of neurons or expression in both neuronal and non-neuronal tissues. Previously we identified BAF53b as a neuron-specific subunit of the chromatin remodeling BAF complexes. Using a bacteria artificial chromosome (BAC) construct containing the BAF53b gene, we generated a Cre transgenic mouse under the control of BAF53b regulatory elements. Like the endogenous BAF53b gene, we showed that BAF53b-Cre is largely neuron-specific. In both central and peripheral nervous systems, it was expressed in all developing neurons examined and was not observed in neural progenitors or glial cells. In addition, BAF53b-Cre functioned in primary cultures in a pan-neuron-specific manner. Thus, BAF53b-Cre mice will be a useful genetic tool to manipulate gene expression in developing neurons for molecular, biochemical, and functional studies.
Collapse
Affiliation(s)
- Xiaoming Zhan
- Department of Physiology and Developmental Biology, University of Texas Southwestern Medical Center, Dallas, Texas.,Center for the Genetics of Host Defense, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Mou Cao
- Department of Physiology and Developmental Biology, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Andrew S Yoo
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, Missouri
| | - Zilai Zhang
- Department of Physiology and Developmental Biology, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Lei Chen
- Department of Pathology and Developmental Biology, Howard Hughes Medical Institute, Stanford University Medical School, Stanford, California
| | - Gerald R Crabtree
- Department of Pathology and Developmental Biology, Howard Hughes Medical Institute, Stanford University Medical School, Stanford, California
| | - Jiang I Wu
- Department of Physiology and Developmental Biology, University of Texas Southwestern Medical Center, Dallas, Texas
| |
Collapse
|
32
|
Levy C, Brooks JM, Chen J, Su J, Fox MA. Cell-specific and developmental expression of lectican-cleaving proteases in mouse hippocampus and neocortex. J Comp Neurol 2014; 523:629-48. [PMID: 25349050 DOI: 10.1002/cne.23701] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Revised: 10/20/2014] [Accepted: 10/21/2014] [Indexed: 12/31/2022]
Abstract
Mounting evidence has demonstrated that a specialized extracellular matrix exists in the mammalian brain and that this glycoprotein-rich matrix contributes to many aspects of brain development and function. The most prominent supramolecular assemblies of these extracellular matrix glycoproteins are perineuronal nets, specialized lattice-like structures that surround the cell bodies and proximal neurites of select classes of interneurons. Perineuronal nets are composed of lecticans, a family of chondroitin sulfate proteoglycans that includes aggrecan, brevican, neurocan, and versican. These lattice-like structures emerge late in postnatal brain development, coinciding with the ending of critical periods of brain development. Despite our knowledge of the presence of lecticans in perineuronal nets and their importance in regulating synaptic plasticity, we know little about the development or distribution of the extracellular proteases that are responsible for their cleavage and turnover. A subset of a large family of extracellular proteases (called a disintegrin and metalloproteinase with thrombospondin motifs [ADAMTS]) is responsible for endogenously cleaving lecticans. We therefore explored the expression pattern of two aggrecan-degrading ADAMTS family members, ADAMTS15 and ADAMTS4, in the hippocampus and neocortex. Here, we show that both lectican-degrading metalloproteases are present in these brain regions and that each exhibits a distinct temporal and spatial expression pattern. Adamts15 mRNA is expressed exclusively by parvalbumin-expressing interneurons during synaptogenesis, whereas Adamts4 mRNA is exclusively generated by telencephalic oligodendrocytes during myelination. Thus, ADAMTS15 and ADAMTS4 not only exhibit unique cellular expression patterns but their developmental upregulation by these cell types coincides with critical aspects of neural development.
Collapse
Affiliation(s)
- C Levy
- Virginia Tech Carilion Research Institute, Roanoke, Virginia, 24016; Department of Biological Sciences, Virginia Tech, Blacksburg, Virginia, 24061
| | | | | | | | | |
Collapse
|
33
|
Iwata R, Ohi K, Kobayashi Y, Masuda A, Iwama M, Yasuda Y, Yamamori H, Tanaka M, Hashimoto R, Itohara S, Iwasato T. RacGAP α2-Chimaerin Function in Development Adjusts Cognitive Ability in Adulthood. Cell Rep 2014; 8:1257-64. [DOI: 10.1016/j.celrep.2014.07.047] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2013] [Revised: 06/20/2014] [Accepted: 07/25/2014] [Indexed: 11/24/2022] Open
|
34
|
de Leeuw CN, Dyka FM, Boye SL, Laprise S, Zhou M, Chou AY, Borretta L, McInerny SC, Banks KG, Portales-Casamar E, Swanson MI, D’Souza CA, Boye SE, Jones SJM, Holt RA, Goldowitz D, Hauswirth WW, Wasserman WW, Simpson EM. Targeted CNS Delivery Using Human MiniPromoters and Demonstrated Compatibility with Adeno-Associated Viral Vectors. Mol Ther Methods Clin Dev 2014; 1:5. [PMID: 24761428 PMCID: PMC3992516 DOI: 10.1038/mtm.2013.5] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2013] [Accepted: 11/05/2013] [Indexed: 01/21/2023]
Abstract
Critical for human gene therapy is the availability of small promoter tools to drive gene expression in a highly specific and reproducible manner. We tackled this challenge by developing human DNA MiniPromoters using computational biology and phylogenetic conservation. MiniPromoters were tested in mouse as single-copy knock-ins at the Hprt locus on the X Chromosome, and evaluated for lacZ reporter expression in CNS and non-CNS tissue. Eighteen novel MiniPromoters driving expression in mouse brain were identified, two MiniPromoters for driving pan-neuronal expression, and 17 MiniPromoters for the mouse eye. Key areas of therapeutic interest were represented in this set: the cerebral cortex, embryonic hypothalamus, spinal cord, bipolar and ganglion cells of the retina, and skeletal muscle. We also demonstrated that three retinal ganglion cell MiniPromoters exhibit similar cell-type specificity when delivered via adeno-associated virus (AAV) vectors intravitreally. We conclude that our methodology and characterization has resulted in desirable expression characteristics that are intrinsic to the MiniPromoter, not dictated by copy number effects or genomic location, and results in constructs predisposed to success in AAV. These MiniPromoters are immediately applicable for pre-clinical studies towards gene therapy in humans, and are publicly available to facilitate basic and clinical research, and human gene therapy.
Collapse
Affiliation(s)
- Charles N de Leeuw
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Frank M Dyka
- Department of Ophthalmology, College of Medicine, University of Florida, Gainesville, Florida, USA
| | - Sanford L Boye
- Department of Ophthalmology, College of Medicine, University of Florida, Gainesville, Florida, USA
| | - Stéphanie Laprise
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Michelle Zhou
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Alice Y Chou
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Lisa Borretta
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Simone C McInerny
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Kathleen G Banks
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Elodie Portales-Casamar
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Magdalena I Swanson
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
| | - Cletus A D’Souza
- Canada’s Michael Smith Genome Sciences Centre, British Columbia Cancer Agency, Vancouver, British Columbia, Canada
| | - Shannon E Boye
- Department of Ophthalmology, College of Medicine, University of Florida, Gainesville, Florida, USA
| | - Steven JM Jones
- Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada
- Canada’s Michael Smith Genome Sciences Centre, British Columbia Cancer Agency, Vancouver, British Columbia, Canada
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia, Canada
| | - Robert A Holt
- Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada
- Canada’s Michael Smith Genome Sciences Centre, British Columbia Cancer Agency, Vancouver, British Columbia, Canada
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, British Columbia, Canada
- Department of Psychiatry, University of British Columbia, Vancouver, British Columbia, Canada
| | - Daniel Goldowitz
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada
| | - William W Hauswirth
- Department of Ophthalmology, College of Medicine, University of Florida, Gainesville, Florida, USA
| | - Wyeth W Wasserman
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Elizabeth M Simpson
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Psychiatry, University of British Columbia, Vancouver, British Columbia, Canada
| |
Collapse
|
35
|
Heimer-McGinn V, Murphy ACH, Kim JC, Dymecki SM, Young PW. Decreased dendritic spine density as a consequence of tetanus toxin light chain expression in single neurons in vivo. Neurosci Lett 2013; 555:36-41. [PMID: 24035894 DOI: 10.1016/j.neulet.2013.09.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2013] [Revised: 08/19/2013] [Accepted: 09/04/2013] [Indexed: 10/26/2022]
Abstract
Tetanus toxin light chain has been used for some time as a genetically-encoded tool to inhibit neurotransmission and thereby dissect mechanisms underlying neural circuit formation and function. In addition to cleaving v-SNARE proteins involved in axonal neurotransmitter release, tetanus toxin light chain can also block activity-dependent dendritic exocytosis. The application of tetanus toxin light chain as a research tool in mammalian models, however, has been limited to a small number of cell types. Here we have induced expression of tetanus toxin light chain in a very small number of fluorescently labeled neurons in many regions of the adult mouse brain. This was achieved by crossing SLICK (single-neuron labeling with inducible cre-mediated knockout) transgenic lines with RC::Ptox mice that have Cre recombinase-controlled expression of the tetanus toxin light chain. Using this system we have examined the cell-autonomous effects of tetanus toxin light chain expression on dendritic spines in vivo. We find that dendritic spine density is reduced by 15% in tetanus toxin expressing hippocampal CA1 pyramidal cells, while spine morphology is unaltered. This effect is likely to be a consequence of inhibition of activity-dependent dendritic exocytosis and suggests that on-going plasticity-associated exocytosis is required for long-term dendritic spine maintenance in vivo.
Collapse
Affiliation(s)
- Victoria Heimer-McGinn
- School of Biochemistry and Cell Biology, University College Cork, Cork, Ireland; Department of Cognitive, Linguistic and Psychological Sciences, Brown University, Providence, RI 02912, USA.
| | | | | | | | | |
Collapse
|
36
|
Lao Z, Raju GP, Bai CB, Joyner AL. MASTR: a technique for mosaic mutant analysis with spatial and temporal control of recombination using conditional floxed alleles in mice. Cell Rep 2012; 2:386-96. [PMID: 22884371 DOI: 10.1016/j.celrep.2012.07.004] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2012] [Revised: 05/11/2012] [Accepted: 07/10/2012] [Indexed: 11/17/2022] Open
Abstract
Mosaic mutant analysis, the study of cellular defects in scattered mutant cells in a wild-type environment, is a powerful approach for identifying critical functions of genes and has been applied extensively to invertebrate model organisms. A highly versatile technique has been developed in mouse: MASTR (mosaic mutant analysis with spatial and temporal control of recombination), which utilizes the increasing number of floxed alleles and simultaneously combines conditional gene mutagenesis and cell marking for fate analysis. A targeted allele (R26(MASTR)) was engineered; the allele expresses a GFPcre fusion protein following FLP-mediated recombination, which serves the dual function of deleting floxed alleles and marking mutant cells with GFP. Within 24 hr of tamoxifen administration to R26(MASTR) mice carrying an inducible FlpoER transgene and a floxed allele, nearly all GFP-expressing cells have a mutant allele. The fate of single cells lacking FGF8 or SHH signaling in the developing hindbrain was analyzed using MASTR, and it was revealed that there is only a short time window when neural progenitors require FGFR1 for viability and that granule cell precursors differentiate rapidly when SMO is lost. MASTR is a powerful tool that provides cell-type-specific (spatial) and temporal marking of mosaic mutant cells and is broadly applicable to developmental, cancer, and adult stem cell studies.
Collapse
Affiliation(s)
- Zhimin Lao
- Developmental Biology Department, Memorial Sloan-Kettering Cancer Center, Weill Cornell Medical College, New York, NY 10065, USA
| | | | | | | |
Collapse
|