Emerging Roles of Filopodia and Dendritic Spines in Motoneuron Plasticity during Development and Disease
Joint Authors
Kanjhan, Refik
Noakes, Peter G.
Bellingham, Mark C.
Source
Issue
Vol. 2016, Issue 2016 (31 Dec. 2016), pp.1-31, 31 p.
Publisher
Hindawi Publishing Corporation
Publication Date
2015-12-30
Country of Publication
Egypt
No. of Pages
31
Main Subjects
Abstract EN
Motoneurons develop extensive dendritic trees for receiving excitatory and inhibitory synaptic inputs to perform a variety of complex motor tasks.
At birth, the somatodendritic domains of mouse hypoglossal and lumbar motoneurons have dense filopodia and spines.
Consistent with Vaughn’s synaptotropic hypothesis, we propose a developmental unified-hybrid model implicating filopodia in motoneuron spinogenesis/synaptogenesis and dendritic growth and branching critical for circuit formation and synaptic plasticity at embryonic/prenatal/neonatal period.
Filopodia density decreases and spine density initially increases until postnatal day 15 (P15) and then decreases by P30.
Spine distribution shifts towards the distal dendrites, and spines become shorter (stubby), coinciding with decreases in frequency and increases in amplitude of excitatory postsynaptic currents with maturation.
In transgenic mice, either overexpressing the mutated human Cu/Zn-superoxide dismutase ( hSOD 1 G 93 A ) gene or deficient in GABAergic/glycinergic synaptic transmission (gephyrin, GAD-67, or VGAT gene knockout), hypoglossal motoneurons develop excitatory glutamatergic synaptic hyperactivity.
Functional synaptic hyperactivity is associated with increased dendritic growth, branching, and increased spine and filopodia density, involving actin-based cytoskeletal and structural remodelling.
Energy-dependent ionic pumps that maintain intracellular sodium/calcium homeostasis are chronically challenged by activity and selectively overwhelmed by hyperactivity which eventually causes sustained membrane depolarization leading to excitotoxicity, activating microglia to phagocytose degenerating neurons under neuropathological conditions.
American Psychological Association (APA)
Kanjhan, Refik& Noakes, Peter G.& Bellingham, Mark C.. 2015. Emerging Roles of Filopodia and Dendritic Spines in Motoneuron Plasticity during Development and Disease. Neural Plasticity،Vol. 2016, no. 2016, pp.1-31.
https://search.emarefa.net/detail/BIM-1113075
Modern Language Association (MLA)
Kanjhan, Refik…[et al.]. Emerging Roles of Filopodia and Dendritic Spines in Motoneuron Plasticity during Development and Disease. Neural Plasticity No. 2016 (2016), pp.1-31.
https://search.emarefa.net/detail/BIM-1113075
American Medical Association (AMA)
Kanjhan, Refik& Noakes, Peter G.& Bellingham, Mark C.. Emerging Roles of Filopodia and Dendritic Spines in Motoneuron Plasticity during Development and Disease. Neural Plasticity. 2015. Vol. 2016, no. 2016, pp.1-31.
https://search.emarefa.net/detail/BIM-1113075
Data Type
Journal Articles
Language
English
Notes
Includes bibliographical references
Record ID
BIM-1113075