Precise localization of alpha7 nicotinic acetylcholine receptors on glutamatergic axon terminals in the rat ventral tegmental area.
AuthorsJones IW, Wonnacott S
JournalJ Neurosci
PubMed ID15601930
'Alpha7 neuronal nicotinic acetylcholine receptors (nAChRs) constitute one of the predominant nAChR subtypes in the mammalian brain. Within the ventral tegmental area (VTA), nicotine application, paired with postsynaptic stimulation, contributes to a form of long-term potentiation, an effect attributed to presynaptic alpha7 nAChRs on glutamatergic afferents (Mansvelder and McGehee, 2000). ... More
Thyroid hormone controls the development of connections between the spinal cord and limbs during Xenopus laevis metamorphosis.
AuthorsMarsh-Armstrong N, Cai L, Brown DD
JournalProc Natl Acad Sci U S A
PubMed ID14691251
'During premetamorphic stages, Xenopus laevis tadpoles expressing either a dominant-negative thyroid hormone (TH) receptor or a type-III iodothyronine deiodinase transgene in the nervous system have reduced TH-induced proliferation in the spinal cord and produce fewer hindlimb-innervating motorneurons. During prometamorphic stages, innervation of the hindlimbs is reduced, and few functional neuromuscular ... More
Syncoilin, a novel member of the intermediate filament superfamily that interacts with alpha-dystrobrevin in skeletal muscle.
AuthorsNewey SE, Howman EV, Ponting CP, Benson MA, Nawrotzki R, Loh NY, Davies KE, Blake DJ
JournalJ Biol Chem
PubMed ID11053421
'Dystrophin coordinates the assembly of a complex of structural and signaling proteins that are required for normal muscle function. A key component of the dystrophin protein complex is alpha-dystrobrevin, a dystrophin-associated protein whose absence results in neuromuscular junction defects and muscular dystrophy. To gain further insights into the role of ... More
The dynamics of the rapsyn scaffolding protein at individual acetylcholine receptor clusters.
AuthorsBruneau E, Akaaboune M
JournalJ Biol Chem
PubMed ID17283077
'Rapsyn, a cytoplasmic receptor-associated protein, is required for the clustering of acetylcholine receptors (AChRs). Although AChR dynamics have been extensively studied, little is known about the dynamics of rapsyn. Here, we used a rapsyn-green fluorescent protein (GFP) fusion protein and quantitative fluorescent imaging to study the dynamics of rapsyn in ... More
Carbofuran induces apoptosis of rat cortical neurons and down-regulates surface alpha7 subunit of acetylcholine receptors.
AuthorsKim SJ, Kim JE, Ko BH, Moon IS
JournalMol Cells
PubMed ID15179037
'Carbofuran (CF), an anticholinesterase carbamate, is one of the most widely used N-methylcarbamate esters in insect and nematode control. Despite its serious adverse health effects on wildlife and humans, cellular and molecular studies of the damage of CF to CNS neurons are very limited. We have examined the cytotoxic effects ... More
Local induction of acetylcholine receptor clustering in myotube cultures using microfluidic application of agrin.
AuthorsTourovskaia A, Kosar TF, Folch A
JournalBiophys J
PubMed ID16387765
'During neuromuscular synaptogenesis, the exchange of spatially localized signals between nerve and muscle initiates the coordinated focal accumulation of the acetylcholine (ACh) release machinery and the ACh receptors (AChRs). One of the key first steps is the release of the proteoglycan agrin focalized at the axon tip, which induces the ... More
Postsynaptic chromatin is under neural control at the neuromuscular junction.
AuthorsRavel-Chapuis A, Vandromme M, Thomas JL, Schaeffer L
JournalEMBO J
PubMed ID17304221
'In adult skeletal muscle, the nicotinic acetylcholine receptor (AChR) specifically accumulates at the neuromuscular junction, to allow neurotransmission. This clustering is paralleled by a compartmentalization of AChR genes expression to subsynaptic nuclei, which acquire a unique gene expression program and a specific morphology in response to neural cues. Our results ... More
Dysbindin, a novel coiled-coil-containing protein that interacts with the dystrobrevins in muscle and brain.
AuthorsBenson MA, Newey SE, Martin-Rendon E, Hawkes R, Blake DJ
JournalJ Biol Chem
PubMed ID11316798
'The dystrophin-associated protein complex (DPC) is required for the maintenance of muscle integrity during the mechanical stresses of contraction and relaxation. In addition to providing a membrane scaffold, members of the DPC such as the alpha-dystrobrevin protein family are thought to play an important role in intracellular signal transduction. To ... More
Activity-dependent neurotransmitter-receptor matching at the neuromuscular junction.
AuthorsBorodinsky LN, Spitzer NC
JournalProc Natl Acad Sci U S A
PubMed ID17190810
'Signaling in the nervous system requires matching of neurotransmitter receptors with cognate neurotransmitters at synapses. The vertebrate neuromuscular junction is the best studied cholinergic synapse, but the mechanisms by which acetylcholine is matched with acetylcholine receptors are not fully understood. Because alterations in neuronal calcium spike activity alter transmitter specification ... More
The formation of acetylcholine receptor clusters visualized with quantum dots.
AuthorsGeng L, Zhang HL, Peng HB,
JournalBMC Neurosci
PubMed ID19604411
BACKGROUND: Motor innervation of skeletal muscle leads to the assembly of acetylcholine receptor (AChR) clusters in the postsynaptic membrane at the vertebrate neuromuscular junction (NMJ). Synaptic AChR aggregation, according to the diffusion-mediated trapping hypothesis, involves the establishment of a postsynaptic scaffold that ... More
Counting the number of proteins coupled to single nanoparticles.
AuthorsCasanova D, Giaume D, Moreau M, Martin JL, Gacoin T, Boilot JP, Alexandrou A,
JournalJ Am Chem Soc
PubMed ID17902659
We coupled lanthanide-ion doped oxide anoparticles to a protein, alpha-bungarotoxin, already labeled with an organic fluorophore (Alexa Fluor 488) with a 1:1 stoichiometry. We thenused the stepwise photobleaching of the organic fluorophoresattached to individual NPs to quantify the protein-NP ratio for eachNP as well as its distribution. ... More
Single-molecule imaging of a fluorescent unnatural amino acid incorporated into nicotinic receptors.
AuthorsPantoja R, Rodriguez EA, Dibas MI, Dougherty DA, Lester HA,
JournalBiophys J
PubMed ID19134478
We report on the first, to our knowledge, successful detection of a fluorescent unnatural amino acid (fUAA), Lys(BODIPYFL), incorporated into a membrane protein (the muscle nicotinic acetylcholine receptor, nAChR) in a living cell. Xenopus oocytes were injected with a frameshift-suppressor tRNA, amino-acylated with Lys(BODIPYFL) and nAChR (alpha/beta19'GGGU/gamma/delta) mRNAs. We measured ... More
Fluorophore-assisted light inactivation produces both targeted and collateral effects on N-type calcium channel modulation in rat sympathetic neurons.
AuthorsGuo J, Chen H, Puhl HL, Ikeda SR,
JournalJ Physiol
PubMed ID16873413
Fluorophore-assisted light inactivation (FALI) is a method to inactivate specific proteins on a time scale of seconds to minutes using either diffuse or coherent light. Here we examine a novel FALI modality that utilizes a fluorescein-conjugated polypeptide, alpha-bungarotoxin (BTX) and a 13 amino acid BTX-binding site engineered into the N-terminus ... More
Functional properties of alpha7 nicotinic acetylcholine receptors co-expressed with RIC-3 in a stable recombinant CHO-K1 cell line.
Heterologous functional expression of alpha7 nicotinic acetylcholine receptors (nAChRs) is difficult to achieve in mammalian cell lines, and the reasons have been associated with a lack of expression of the putative chaperone factor RIC-3. Here, we describe the generation and functional and pharmacological characterization of a Chinese hamster ovary (CHO)-K1 ... More
Neurotransmitter receptor dynamics studied in vivo by reversible photo-unbinding of fluorescent ligands.
AuthorsAkaaboune M, Grady RM, Turney S, Sanes JR, Lichtman JW
JournalNeuron
PubMed ID12086635
We show that fluorescently tagged ligands with high affinity for their targets can be reversibly unbound by focused laser excitation. By sequential unbinding and relabeling with different colors of alpha-bungarotoxin, we selectively labeled adjacent pools of acetylcholine receptors (AChRs) at neuromuscular junctions of adult mice. Timelapse imaging in vivo revealed ... More
Nicotinic acetylcholine receptor is internalized via a Rac-dependent, dynamin-independent endocytic pathway.
AuthorsKumari S, Borroni V, Chaudhry A, Chanda B, Massol R, Mayor S, Barrantes FJ,
JournalJ Cell Biol
PubMed ID18591431
Endocytosis of the nicotinic acetylcholine receptor (AChR) is a proposed major mechanism of neuromodulation at neuromuscular junctions and in the pathology of synapses in the central nervous system. We show that binding of the competitive antagonist alpha-bungarotoxin (alphaBTX) or antibody-mediated cross-linking induces the internalization of cell surface AChR to late ... More
Agrin mediates a rapid switch from electrical coupling to chemical neurotransmission during synaptogenesis.
AuthorsMartin AO, Alonso G, Guérineau NC
JournalJ Cell Biol
PubMed ID15883200
In contrast to its well-established actions as an organizer of synaptic differentiation at the neuromuscular junction, the proteoglycan agrin is still in search of a function in the nervous system. Here, we report an entirely unanticipated role for agrin in the dual modulation of electrical and chemical intercellular communication that ... More
Toxicity from different SOD1 mutants dysregulates the complement system and the neuronal regenerative response in ALS motor neurons.
AuthorsLobsiger CS, Boillée S, Cleveland DW
JournalProc Natl Acad Sci U S A
PubMed ID17463094
Global, age-dependent changes in gene expression from rodent models of inherited ALS caused by dominant mutations in superoxide-dismutase 1 (SOD1) were identified by using gene arrays and RNAs isolated from purified embryonic and adult motor neurons. Comparison of embryonic motor neurons expressing a dismutase active ALS-linked mutant SOD1 with those ... More
Localisation of the high-affinity choline transporter-1 in the rat skeletal motor unit.
AuthorsLips KS, Pfeil U, Haberberger RV, Kummer W
JournalCell Tissue Res
PubMed ID11904763
The rate-limiting step in neuronal acetylcholine (ACh) synthesis is the uptake of choline via a high-affinity transporter. We have generated antisera against the recently identified transporter CHT1 to investigate its distribution in rat motor neurons and skeletal muscle and have used these antisera in combination with (1) antisera against the ... More
Peptide tags for labeling membrane proteins in live cells with multiple fluorophores.
AuthorsMcCann CM, Bareyre FM, Lichtman JW, Sanes JR
JournalBiotechniques
PubMed ID16018556
We describe a method to label specific membrane proteins with fluorophores for live imaging. Fusion proteins are generated that incorporate into their extracellular domains short peptide sequences (13-38 amino acids) recognized with high affinity and specificity by protein ligands, alpha-bungarotoxin (BTX), or streptavidin (SA). Many fluorophore- and enzyme-conjugated derivatives of ... More
A- and B-utrophin have different expression patterns and are differentially up-regulated in mdx muscle.
AuthorsWeir AP, Burton EA, Harrod G, Davies KE
JournalJ Biol Chem
PubMed ID12235137
Duchenne muscular dystrophy (DMD) is a fatal childhood disease caused by mutations that abolish the expression of dystrophin in muscle. Utrophin is a paralogue of dystrophin and can functionally replace it in skeletal muscle. A method to induce utrophin up-regulation in muscle should therefore be therapeutically useful in DMD. We ... More
Acetylcholinesterase dynamics at the neuromuscular junction of live animals.
AuthorsKrejci E, Martinez-Pena y Valenzuela I, Ameziane R, Akaaboune M
JournalJ Biol Chem
PubMed ID16455662
At cholinergic synapses, acetylcholinesterase (AChE) is critical for ensuring normal synaptic transmission. However, little is known about how this enzyme is maintained and regulated in vivo. In this work, we demonstrate that the dissociation of fluorescently-tagged fasciculin 2 (a specific and selective peptide inhibitor of AChE) from AChE is extremely ... More
Identification of sequence motifs that target neuronal nicotinic receptors to dendrites and axons.
AuthorsXu J, Zhu Y, Heinemann SF
JournalJ Neurosci
PubMed ID16988049
Neuronal nicotinic acetylcholine receptors (nAChRs) belong to a family of ligand-gated ion channels that play important roles in central and peripheral nervous systems. The subcellular distribution of neuronal nAChRs has important implications for function and is not well understood. Here, we analyzed the targeting of two major types of neuronal ... More
Differential Vicia villosa agglutinin reactivity identifies three distinct dystroglycan complexes in skeletal muscle.
AuthorsMcDearmon EL, Combs AC, Ervasti JM
JournalJ Biol Chem
PubMed ID11459841
We present evidence for the expression of three alpha-dystroglycan glycoforms in skeletal muscle cells, including two minor glycoforms marked by either patent or latent reactivity with the N-acetylgalactosamine-specific lectin Vicia villosa agglutinin. Both minor glycoforms co-isolated with beta-dystroglycan, but not with other dystrophin/utrophin-glycoprotein complex components, suggesting that they may perform ... More
The neuromuscular junction is a focal point of mTORC1 signaling in sarcopenia.
Authors
JournalNat Commun
PubMed ID32908143
Opposed Actions of PKA Isozymes (RI and RII) and PKC Isoforms (cPKCßI and nPKCe) in Neuromuscular Developmental Synapse Elimination.
AuthorsGarcia N, Balañà C, Lanuza MA, Tomàs M, Cilleros-Mañé V, Just-Borràs L, Tomàs J
JournalCells
PubMed ID31652775
'During neuromuscular junction (NMJ) development, synapses are produced in excess. By sensing the activity-dependent release of ACh, adenosine, and neurotrophins, presynaptic receptors prompt axonal competition and loss of the unnecessary axons. The receptor action is mediated by synergistic and antagonistic relations when they couple to downstream kinases (mainly protein kinases ... More
Nerve lengthening and subsequent end-to-end repair yield more favourable outcomes compared with autograft repair of rat sciatic nerve defects.
AuthorsHowarth HM, Kadoor A, Salem R, Nicolds B, Adachi S, Kanaris A, Lovering RM, Brown JM, Shah SB
JournalJ Tissue Eng Regen Med
PubMed ID31670904
'Outcomes of end-to-end nerve repairs are more successful compared with outcomes of repairs bridged by nerve grafts. However, end-to-end repairs are not always possible for large nerve gaps, as excessive tension may cause catastrophic failure. In this study, we built on previous nerve-lengthening studies to test the hypotheses that gradual ... More
A comparative assessment of lengthening followed by end-to-end repair and isograft repair of chronically injured peripheral nerves.
AuthorsHowarth HM, Orozco E, Lovering RM, Shah SB
JournalExp Neurol
PubMed ID32333909
'In order to repair chronic nerve injuries (injuries repaired after a long delay), the damaged nerve segments are resected and stumps are bridged by grafts. Autografts remain the gold-standard, but outcomes are typically poor, even after long periods of recovery. In a recent study, we described the use of a ... More
Snake Venom Gland Organoids.
Authors
JournalCell
PubMed ID31978343
Stretchable, dynamic covalent polymers for soft, long-lived bioresorbable electronic stimulators designed to facilitate neuromuscular regeneration.
Authors
JournalNat Commun
PubMed ID33239608
Neuromuscular junction formation between human stem cell-derived motoneurons and human skeletal muscle in a defined system.
Authors
JournalBiomaterials
PubMed ID21944471
Multi-omic analysis of selectively vulnerable motor neuron subtypes implicates altered lipid metabolism in ALS.
Authors
JournalNat Neurosci
PubMed ID34782793
Identification of therapeutics that target eEF1A2 and upregulate utrophin A translation in dystrophic muscles.
Authors
JournalNat Commun
PubMed ID32332749
GDE2 is essential for neuronal survival in the postnatal mammalian spinal cord.
Authors
JournalMol Neurodegener
PubMed ID28103900
Bi-allelic variants in RNF170 are associated with hereditary spastic paraplegia.
Authors
JournalNat Commun
PubMed ID31636353
Tethered agonist exposure in intact adhesion/class B2 GPCRs through intrinsic structural flexibility of the GAIN domain.
Authors
JournalMol Cell
PubMed ID33497605
Mutant TDP-43 within motor neurons drives disease onset but not progression in amyotrophic lateral sclerosis.
Authors
JournalActa Neuropathol
PubMed ID28357566
Reactivation of Denervated Schwann Cells by Embryonic Spinal Cord Neurons to Promote Axon Regeneration and Remyelination.
AuthorsFang X, Zhang C, Zhang C, Cai Y, Yu Z, Huang Z, Li W, Zhang W
JournalStem Cells Int
PubMed ID31885623
In peripheral nerve injuries (PNIs) in which proximal axons do not regenerate quickly enough, significant chronic degeneration of Schwann cells (SCs) can occur at the distal stump of the injured nerve and obstruct regeneration. Cell transplantation can delay the degeneration of SCs, but transplanted cells fail to generate voluntary electrical ... More
Micropatterned substrates with physiological stiffness promote cell maturation and Pompe disease phenotype in human induced pluripotent stem cell-derived skeletal myocytes.
AuthorsJiwlawat N, Lynch EM, Napiwocki BN, Stempien A, Ashton RS, Kamp TJ, Crone WC, Suzuki M
JournalBiotechnol Bioeng
PubMed ID31131875
Recent advances in bioengineering have enabled cell culture systems that more closely mimic the native cellular environment. Here, we demonstrated that human induced pluripotent stem cell (iPSC)-derived myogenic progenitors formed highly-aligned myotubes and contracted when seeded on two-dimensional micropatterned platforms. The differentiated cells showed clear nuclear alignment and formed elongated ... More