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Claudine Cohen-addad - One of the best experts on this subject based on the ideXlab platform.
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Preliminary Crystallographic Study of a Complex Formed between the α/β-Tubulin Heterodimer and the Neuronal Growth-Associated Protein SCG10
Journal of Structural Biology, 2000Co-Authors: D. Fleury, Gabriele Grenningloh, Laurence Lafanechère, Bruno Antonsson, Didier Job, Claudine Cohen-addadAbstract:Crystals of a complex formed between the alpha/beta-tubulin heterodimer and SCG10, a neuron-specific Growth-Associated Protein, have been obtained by the hanging drop method. They belong to the space group P2(1)2(1)2(1), with unit cell parameters a = 56 A, b = 353 A, c = 466 A and four molecular complexes in the asymmetric unit. A complete X-ray diffraction data set to 6.1 A resolution has been collected using synchrotron radiation. This represents a challenging opportunity to study at a molecular level the structure-function relationships between a microtubule-destabilizing Protein, SCG10, and tubulin.
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Preliminary Crystallographic Study of a Complex Formed between the α/β-Tubulin Heterodimer and the Neuronal Growth-Associated Protein SCG10
Journal of structural biology, 2000Co-Authors: D. Fleury, Gabriele Grenningloh, Laurence Lafanechère, Bruno Antonsson, Didier Job, Claudine Cohen-addadAbstract:Crystals of a complex formed between the α/β-tubulin heterodimer and SCG10, a neuron-specific Growth-Associated Protein, have been obtained by the hanging drop method. They belong to the space group P212121, with unit cell parameters a = 56 A, b = 353 A, c = 466 A and four molecular complexes in the asymmetric unit. A complete X-ray diffraction data set to 6.1 A resolution has been collected using synchrotron radiation. This represents a challenging opportunity to study at a molecular level the structure–function relationships between a microtubule-destabilizing Protein, SCG10, and tubulin.
D. Fleury - One of the best experts on this subject based on the ideXlab platform.
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Preliminary Crystallographic Study of a Complex Formed between the α/β-Tubulin Heterodimer and the Neuronal Growth-Associated Protein SCG10
Journal of Structural Biology, 2000Co-Authors: D. Fleury, Gabriele Grenningloh, Laurence Lafanechère, Bruno Antonsson, Didier Job, Claudine Cohen-addadAbstract:Crystals of a complex formed between the alpha/beta-tubulin heterodimer and SCG10, a neuron-specific Growth-Associated Protein, have been obtained by the hanging drop method. They belong to the space group P2(1)2(1)2(1), with unit cell parameters a = 56 A, b = 353 A, c = 466 A and four molecular complexes in the asymmetric unit. A complete X-ray diffraction data set to 6.1 A resolution has been collected using synchrotron radiation. This represents a challenging opportunity to study at a molecular level the structure-function relationships between a microtubule-destabilizing Protein, SCG10, and tubulin.
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Preliminary Crystallographic Study of a Complex Formed between the α/β-Tubulin Heterodimer and the Neuronal Growth-Associated Protein SCG10
Journal of structural biology, 2000Co-Authors: D. Fleury, Gabriele Grenningloh, Laurence Lafanechère, Bruno Antonsson, Didier Job, Claudine Cohen-addadAbstract:Crystals of a complex formed between the α/β-tubulin heterodimer and SCG10, a neuron-specific Growth-Associated Protein, have been obtained by the hanging drop method. They belong to the space group P212121, with unit cell parameters a = 56 A, b = 353 A, c = 466 A and four molecular complexes in the asymmetric unit. A complete X-ray diffraction data set to 6.1 A resolution has been collected using synchrotron radiation. This represents a challenging opportunity to study at a molecular level the structure–function relationships between a microtubule-destabilizing Protein, SCG10, and tubulin.
Lynne C. Weaver - One of the best experts on this subject based on the ideXlab platform.
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Co-localization of substance P and dopamine β-hydroxylase with Growth-Associated Protein-43 is lost caudal to a spinal cord transection
Neuroscience, 1999Co-Authors: A.k Cassam, K.a Rogers, Lynne C. WeaverAbstract:After spinal cord injury, abnormal responses of spinal cord neurons to sensory input lead to conditions such as autonomic dysreflexia, urinary bladder dyssynergia, muscle spasticity and chronic pain syndromes. These responses suggest that the spinal cord undergoes marked reorganization after an injury. In previous studies, we demonstrated changes in individual patterns of immunoreactivity for Growth-Associated Protein-43, dopamine β-hydroxylase and substance P that suggest Growth and/or changes in expression of neurotransmitter enzymes and peptides in the cord caudal to a transection injury. In the present study we determined (i) if Growth-Associated Protein-43 and dopamine β-hydroxylase or substance P were co-expressed in the same neurons prior to cord injury, and (ii) if these patterns of expression changed after injury. A change in co-localization patterns caudal to an injury would suggest diversity in responses of different populations of spinal neurons. We used double-labelling immunocytochemistry to determine if either dopamine β-hydroxylase or substance P were co-localized with Growth-Associated Protein-43 in control rats and in rats one, two or six weeks after spinal cord transection. We focused on the intermediate gray matter, especially the sympathetic intermediolateral cell column. In control rats, fibres travelling in a stereotyped ladder-like pattern in the thoracic gray matter contained Growth-Associated Protein-43 co-localized with dopamine β-hydroxylase or substance P. In spinal rats, such co-localization was also observed in spinal cord segments rostral to the cord transection. In contrast, caudal to the transection, substance P and Growth-Associated Protein-43 were found in separate reticular networks. Immunoreactivity for dopamine β-hydroxylase disappeared in fibres during this time, but was clearly present in somata. Immunoreactivity for Growth-Associated Protein-43 was also found in somata, but never co-localized with that for dopamine β-hydroxylase. These observations demonstrated co-localization of Growth-Associated Protein-43 with dopamine β-hydroxylase and substance P in descending spinal cord pathways. Caudal to a cord transection, this co-localization was no longer found, although each substance was present either in an abundant neural network or in somata. One population of spinal neurons responded to cord injury by expressing the Growth-Associated Protein, whereas two others changed in the intensity of their expression of neurotransmitter peptides or enzymes or in the abundance of fibres expressing them. Thus, three populations of spinal neurons had distinct responses to cord injury, two of them increasing their potential input to spinal sensory, sympathetic or motor neurons. Such responses would enhance transmission through spinal pathways after cord injury.
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Changes in immunoreactivity for Growth Associated Protein-43 suggest reorganization of synapses on spinal sympathetic neurons after cord transection
Neuroscience, 1997Co-Authors: Lynne C. Weaver, A.k Cassam, Andrei V. Krassioukov, Ida J. Llewellyn-smithAbstract:Cervical or high thoracic spinal cord injury often results in autonomic dysreflexia, a condition characterized by exaggerated spinal reflexes and episodic hypertension, that may be caused by reorganization of synapses on sympathetic preganglionic neurons after loss of supraspinal input. To assess remodelling of synaptic input to identified preganglionic neurons, immunoreactivity for Growth Associated Protein-43 was examined by fluorescent and electron microscopy in control rats with intact spinal cords and in rats seven to 30 days after midthoracic cord transection. This Protein is found in mature bulbospinal axons that supply spinal sympathetic nuclei and it is also known to be up-regulated in growing or sprouting axons. In the thoracic cord of control rats, fibres containing Growth Associated Protein-43 surrounded histochemically- or retrogradely-labelled preganglionic neurons and formed a ladder-like pattern in the gray matter. Fibres travelled rostrocaudally along the lateral horn and, at approximately regular intervals, they coursed mediolaterally to form "rungs" of a ladder. Electron microscopy revealed concentrated Growth Associated Protein-43 in many intervaricose axon segments in the intermediolateral cell column. Less frequently, faint immunoreactivity for this Protein was found in varicosities, some of which synapsed on retrogradely-labelled sympathoadrenal preganglionic neurons. Electron microscopy of conventionally processed tissue was used to determine the time-course of degeneration of severed axon terminals in the intermediolateral cell column. In spinal rats, terminals with ultrastructural signs of degeneration were numerous in the intermediolateral cell column three days after transection, but were rare at seven days and absent at 14 days. Degenerating terminals were never found in this region in control rats. Thus virtually all supraspinal inputs to preganglionic neurons had been eliminated by seven days after transection. At longer times after injury, terminals containing immunoreactivity for Growth Associated Protein-43 must therefore arise from intraspinal neurons. The distribution of fibres immunoreactive for Growth Associated Protein-43 changed markedly in the first 30 days after cord transection. By 14 days, the ladder-like pattern was distorted rostral to the transection by enlarged masses of immunoreactive fibres surrounding preganglionic neurons, suggesting sprouting of bulbospinal or intraspinal axons or accumulation of this Protein in their terminals after the parent axon had been severed. Caudal to the transection, the ladder-like arrangement of fibres was completely replaced by a reticular network of immunoreactive fibres that extended throughout the intermediate gray matter and increased in density between 14 and 30 days. In the intermediolateral cell column, at fourteen days after transection, axons with the ultrastructural features of Growth cones contained intense Growth Associated Protein-43 immunoreactivity. Although varicosities of bulbospinal axons containing this Protein had degenerated by 14 days, weak immunoreactivity was still found in varicosities that synapsed on labelled sympathoadrenal neurons. Furthermore, immunoreactivity appeared in numerous somata of presumed interneurons throughout the intermediate gray matter by 14 days and the number of somata increased by 30 days. These interneurons may be the source of this Protein in the reticular network, and in Growth cones and synapses. The loss of supraspinal inputs by seven days after cord transection, and the new intraspinal network of immunoreactive fibres, synapses and cells are consistent with new synapse formation on preganglionic neurons. New synpases on preganglionic neurons may be crucial for the development of autonomic dysreflexia.
Maria A. Mariggiò - One of the best experts on this subject based on the ideXlab platform.
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Evidence for Altered Ca2+ Handling in Growth Associated Protein 43-Knockout Skeletal Muscle
Frontiers in physiology, 2016Co-Authors: Giusy A. Caprara, Caterina Morabito, Stefano Perni, Riccardo Navarra, Simone Guarnieri, Maria A. MariggiòAbstract:Neuronal Growth-Associated Protein 43 (GAP43) has crucial roles in the nervous system, and during development, regeneration after injury, and learning and memory. GAP43 is expressed in mouse skeletal muscle fibers and satellite cells, with suggested its involvement in intracellular Ca2+ handling. However, the physiological role of GAP43 in muscle remains unknown. Using a GAP43-knockout (GAP43-/-) mouse, we have defined the role of GAP43 in skeletal muscle. GAP43-/- mice showed low survival beyond weaning, reduced adult body weight, decreased muscle strength, and changed myofiber ultrastructure, with no significant differences in the expression of markers of satellite cell and myotube progression through the myogenic program. Thus GAP43 expression is involved in timing of muscle maturation in-vivo. Intracellular Ca2+ measurements in-vitro in myotubes revealed GAP43 involvement in Ca2+ handling. In the absence of GAP43 expression, the spontaneous Ca2+ variations had greater amplitudes and higher frequency. In GAP43-/- myotubes, also the intracellular Ca2+ variations induced by the activation of dihydropyridine and ryanodine Ca2+ channels, resulted modified. These evidences suggested dysregulation of Ca2+ homeostasis. The emerging hypothesis indicates that GAP43 interacts with calmodulin to indirectly modulate the activities of dihydropyridine and ryanodine Ca2+ channels. This thus influences intracellular Ca2+ dynamics and its related intracellular patterns, from functional excitation-contraction coupling, to cell metabolism, and gene expression.
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Growth Associated Protein 43 Is Expressed in Skeletal Muscle Fibers and Is Localized in Proximity of Mitochondria and Calcium Release Units
2013Co-Authors: Simone Guarnieri, Caterina Morabito, Cecilia Paolini, Simona Boncompagni, Raffaele Pilla, Giorgio Fanò-illic, Maria A. MariggiòAbstract:The neuronal Growth Associated Protein 43 (GAP43), also known as B-50 or neuromodulin, is involved in mechanisms controlling pathfinding and branching of neurons during development and regeneration. For many years this Protein was classified as neuron-specific, but recent evidences suggest that a) GAP43 is expressed in the nervous system not only in neurons, but also in glial cells, and b) probably it is present also in other tissues. In particular, its expression was revealed in muscles from patients affected by various myopathies, indicating that GAP43 can no-longer considered only as a neuron-specific molecule. We have investigated the expression and subcellular localization of GAP43 in mouse satellite cells, myotubes, and adult muscle (extensor digitorum longus or EDL) using Western blotting, immuno-fluorescence combined to confocal microscopy and electron microscopy. Our in vitro results indicated that GAP43 is indeed expressed in both myoblasts and differentiating myotubes, and its cellular localization changes dramatically during maturation: in myoblasts the localization appeared to be mostly nuclear, whereas with differentiation the Protein started to display a sarcomeric-like pattern. In adult fibers, GAP43 expression was evident with the Protein labeling forming (in longitudinal views) a double cross striation reminiscent of the staining pattern of other organelles, such as calcium release units (CRUs) and mitochondria. Double immuno-staining and experiments done in EDL muscles fixed at different sarcomere lengths, allowed us to determine the localization, from the sarcomere Z-line, of GAP43 positive foci, falling between that of CRUs and of mitochondria. Staining of cross sections added a detail to the puzzle: GAP43 labeling formed a reticular pattern surrounding individual myofibrils, but excluding contractile elements. This work leads the way to further investigation about the possible physiological and structural role of GAP43 Protein in adult fiber function and disease.
Didier Job - One of the best experts on this subject based on the ideXlab platform.
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Preliminary Crystallographic Study of a Complex Formed between the α/β-Tubulin Heterodimer and the Neuronal Growth-Associated Protein SCG10
Journal of Structural Biology, 2000Co-Authors: D. Fleury, Gabriele Grenningloh, Laurence Lafanechère, Bruno Antonsson, Didier Job, Claudine Cohen-addadAbstract:Crystals of a complex formed between the alpha/beta-tubulin heterodimer and SCG10, a neuron-specific Growth-Associated Protein, have been obtained by the hanging drop method. They belong to the space group P2(1)2(1)2(1), with unit cell parameters a = 56 A, b = 353 A, c = 466 A and four molecular complexes in the asymmetric unit. A complete X-ray diffraction data set to 6.1 A resolution has been collected using synchrotron radiation. This represents a challenging opportunity to study at a molecular level the structure-function relationships between a microtubule-destabilizing Protein, SCG10, and tubulin.
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Preliminary Crystallographic Study of a Complex Formed between the α/β-Tubulin Heterodimer and the Neuronal Growth-Associated Protein SCG10
Journal of structural biology, 2000Co-Authors: D. Fleury, Gabriele Grenningloh, Laurence Lafanechère, Bruno Antonsson, Didier Job, Claudine Cohen-addadAbstract:Crystals of a complex formed between the α/β-tubulin heterodimer and SCG10, a neuron-specific Growth-Associated Protein, have been obtained by the hanging drop method. They belong to the space group P212121, with unit cell parameters a = 56 A, b = 353 A, c = 466 A and four molecular complexes in the asymmetric unit. A complete X-ray diffraction data set to 6.1 A resolution has been collected using synchrotron radiation. This represents a challenging opportunity to study at a molecular level the structure–function relationships between a microtubule-destabilizing Protein, SCG10, and tubulin.
