Organization of cytoskeletal elements and organelles preceding growth cone emergence from an identified neuron in situ.
Frances Lefcort,David R. Bentley +1 more
TLDR
The data suggest that intrinsic information determines the site of growth cone emergence of an identified neuron in situ at thesite of emergence of its growth cone just before and concurrent with the onset of axonogenesis.Abstract:
The purpose of this study was to investigate the arrangement of cytoskeletal elements and organelles in an identified neuron in situ at the site of emergence of its growth cone just before and concurrent with the onset of axonogenesis. The Ti1 pioneer neurons are the first pair of afferent neurons to differentiate in embryonic grasshopper limbs. They arise at the distal tip of the limb bud epithelium, the daughter cells of a single precursor cell, the Pioneer Mother Cell (PMC). Using immunohistochemical markers, we characterized the organization of microtubules, centrosomes, Golgi apparatus, midbody, actin filaments, and chromatin from mitosis in the PMC through axonogenesis in the Tils. Just before and concurrent with the onset of axonogenesis, a characteristic arrangement of tubulin, actin filaments, and Golgi apparatus is localized at the proximal pole of the proximal pioneer neuron. The growth cone of the proximal cell stereotypically arises from this site. Although the distal cell's axon generally grows proximally, occasionally it arises from its distal pole; in such limbs, the axons from the sister cells extend from mirror symmetric locations on their somata. In the presence of cytochalasin D, the PMC undergoes nuclear division but not cytokinesis and although other neuronal phenotypes are expressed, axongenesis is inhibited. Our data suggest that intrinsic information determines the site of growth cone emergence of an identified neuron in situ.read more
Citations
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Microtubule assembly, organization and dynamics in axons and dendrites.
Cecilia Conde,Alfredo Cáceres +1 more
TL;DR: Current understanding of the regulation of microtubule assembly, organization and dynamics in axons and dendrites is reviewed to provide new insight into microtubules' function in neuronal development and their potential contribution to plasticity.
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Distinct morphogenetic functions of similar small GTPases: Drosophila Drac1 is involved in axonal outgrowth and myoblast fusion.
TL;DR: Cloned Drosophila homologs of rac and CDC42, Drac1, and Dcdc42 proteins cause qualitatively distinct morphological defects, suggesting that similar GTPases in the same subfamily have unique roles in morphogenesis.
Journal ArticleDOI
Neuronal polarity: from extracellular signals to intracellular mechanisms
Nariko Arimura,Kozo Kaibuchi +1 more
TL;DR: After they are born and differentiate, neurons break their previous symmetry, dramatically change their shape, and establish two structurally and functionally distinct compartments — axons and dendrites — within one cell.
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Fasciclin IV: Sequence, expression, and function during growth cone guidance in the grasshopper embryo
Alex L. Kolodkin,David Matthes,Timothy O'connor,Nipam H. Patel,Arie Admon,David R. Bentley,Corey S. Goodman +6 more
TL;DR: CDNA sequence analysis suggests that fasciclin IV appears to be a novel integral membrane protein that functions in growth cone guidance.
Journal ArticleDOI
UNC-6/Netrin induces neuronal asymmetry and defines the site of axon formation
TL;DR: By directly observing developing neurons in vivo, it is shown that UNC-6 and UNC-40 also function during axon formation to initiate, maintain and orient asymmetric neuronal growth.
References
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Journal ArticleDOI
The establishment of polarity by hippocampal neurons in culture
TL;DR: By the end of the first week in culture, hippocampal neurons have established a single axon and several dendrites, which is a stereotyped sequence of developmental events that lead to the establishment of this characteristic form.
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Beyond self-assembly: from microtubules to morphogenesis
Journal ArticleDOI
An evaluation of confocal versus conventional imaging of biological structures by fluorescence light microscopy.
TL;DR: It is found that confocal imaging gives greatly enhanced images of biological structures viewed with epifluorescence, and the improvements are such that it is possible to optically section thick specimens with little degradation in the image quality of interior sections.
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Actions of cytochalasins on the organization of actin filaments and microtubules in a neuronal growth cone.
Paul Forscher,Stephen J. Smith +1 more
TL;DR: Results suggest that actin normally polymerizes at the leading edge and then flows rearward at a rate between 3-6 microns/min, which is consistent with their being secondary to effects of CB on lamellar F-actin.
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Antibodies to horseradish peroxidase as specific neuronal markers in Drosophila and in grasshopper embryos
Lily Yeh Jan,Yuh Nung Jan +1 more
TL;DR: It is shown that mutations affecting segmentation in Drosophila affect the organization of the embryonic nervous system and the anti-HRPeroxase antibodies are used to show this.
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