Abstract
To understand the role of microtubules in growth cone turning, we observed fluorescently labeled microtubules in neurons as they encountered a substrate boundary. Neurons growing on a laminin-rich substrate avoided growing onto collagen type IV. Turning growth cones assumed heterogeneous morphologies and behaviors that depended primarily in their extent of adhesion to the substrate. We grouped these behaviors into three categories-sidestepping, motility, and growth-mediated reorientation. In sidestepping and motility-mediated reorientation, the growth cone and parts of the axon were not well attached to the substrate so the acquisition of an adherent lamella caused the entire growth cone to move away from the border and consequently reoriented the axon. In these cases, since the motility of the growth cone dominates its reorientation, the microtubules were passive, and reorientation occurred without significant axon growth. In growth-mediated reorientation, the growth cone and axon were attached to the substrate. In this case, microtubules reoriented within the growth cone to stabilize a lamella. Bundling of the reoriented microtubules was followed by growth cone collapse to form new axon, and further, polarized lamellipodial extension. These observations indicate that when the growth cone remains adherent to the substrate during turning, the reorientation and bundling of microtubules is an important, early step in growth cone turning.
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Selected References
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- Aletta J. M., Greene L. A. Growth cone configuration and advance: a time-lapse study using video-enhanced differential interference contrast microscopy. J Neurosci. 1988 Apr;8(4):1425–1435. doi: 10.1523/JNEUROSCI.08-04-01425.1988. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bray D., Chapman K. Analysis of microspike movements on the neuronal growth cone. J Neurosci. 1985 Dec;5(12):3204–3213. doi: 10.1523/JNEUROSCI.05-12-03204.1985. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bray D. Mechanical tension produced by nerve cells in tissue culture. J Cell Sci. 1979 Jun;37:391–410. doi: 10.1242/jcs.37.1.391. [DOI] [PubMed] [Google Scholar]
- Burmeister D. W., Goldberg D. J. Micropruning: the mechanism of turning of Aplysia growth cones at substrate borders in vitro. J Neurosci. 1988 Sep;8(9):3151–3159. doi: 10.1523/JNEUROSCI.08-09-03151.1988. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Cyr J. L., Brady S. T. Molecular motors in axonal transport. Cellular and molecular biology of kinesin. Mol Neurobiol. 1992 Summer-Fall;6(2-3):137–155. doi: 10.1007/BF02780549. [DOI] [PubMed] [Google Scholar]
- Dennerll T. J., Joshi H. C., Steel V. L., Buxbaum R. E., Heidemann S. R. Tension and compression in the cytoskeleton of PC-12 neurites. II: Quantitative measurements. J Cell Biol. 1988 Aug;107(2):665–674. doi: 10.1083/jcb.107.2.665. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Dennerll T. J., Lamoureux P., Buxbaum R. E., Heidemann S. R. The cytomechanics of axonal elongation and retraction. J Cell Biol. 1989 Dec;109(6 Pt 1):3073–3083. doi: 10.1083/jcb.109.6.3073. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Goldberg D. J., Burmeister D. W. Stages in axon formation: observations of growth of Aplysia axons in culture using video-enhanced contrast-differential interference contrast microscopy. J Cell Biol. 1986 Nov;103(5):1921–1931. doi: 10.1083/jcb.103.5.1921. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Goodman C. S., Shatz C. J. Developmental mechanisms that generate precise patterns of neuronal connectivity. Cell. 1993 Jan;72 (Suppl):77–98. doi: 10.1016/s0092-8674(05)80030-3. [DOI] [PubMed] [Google Scholar]
- Gundersen R. W. Response of sensory neurites and growth cones to patterned substrata of laminin and fibronectin in vitro. Dev Biol. 1987 Jun;121(2):423–431. doi: 10.1016/0012-1606(87)90179-5. [DOI] [PubMed] [Google Scholar]
- Harris W. A., Holt C. E., Bonhoeffer F. Retinal axons with and without their somata, growing to and arborizing in the tectum of Xenopus embryos: a time-lapse video study of single fibres in vivo. Development. 1987 Sep;101(1):123–133. doi: 10.1242/dev.101.1.123. [DOI] [PubMed] [Google Scholar]
- Harris W. A. Local positional cues in the neuroepithelium guide retinal axons in embryonic Xenopus brain. Nature. 1989 May 18;339(6221):218–221. doi: 10.1038/339218a0. [DOI] [PubMed] [Google Scholar]
- Joshi H. C., Chu D., Buxbaum R. E., Heidemann S. R. Tension and compression in the cytoskeleton of PC 12 neurites. J Cell Biol. 1985 Sep;101(3):697–705. doi: 10.1083/jcb.101.3.697. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lamoureux P., Buxbaum R. E., Heidemann S. R. Direct evidence that growth cones pull. Nature. 1989 Jul 13;340(6229):159–162. doi: 10.1038/340159a0. [DOI] [PubMed] [Google Scholar]
- Lin C. H., Forscher P. Cytoskeletal remodeling during growth cone-target interactions. J Cell Biol. 1993 Jun;121(6):1369–1383. doi: 10.1083/jcb.121.6.1369. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Myers P. Z., Bastiani M. J. Growth cone dynamics during the migration of an identified commissural growth cone. J Neurosci. 1993 Jan;13(1):127–143. doi: 10.1523/JNEUROSCI.13-01-00127.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
- O'Connor T. P., Duerr J. S., Bentley D. Pioneer growth cone steering decisions mediated by single filopodial contacts in situ. J Neurosci. 1990 Dec;10(12):3935–3946. doi: 10.1523/JNEUROSCI.10-12-03935.1990. [DOI] [PMC free article] [PubMed] [Google Scholar]
- O'Leary D. D., Koester S. E. Development of projection neuron types, axon pathways, and patterned connections of the mammalian cortex. Neuron. 1993 Jun;10(6):991–1006. doi: 10.1016/0896-6273(93)90049-w. [DOI] [PubMed] [Google Scholar]
- Schnapp B. J., Vale R. D., Sheetz M. P., Reese T. S. Microtubules and the mechanism of directed organelle movement. Ann N Y Acad Sci. 1986;466:909–918. doi: 10.1111/j.1749-6632.1986.tb38476.x. [DOI] [PubMed] [Google Scholar]
- Shaw G., Bray D. Movement and extension of isolated growth cones. Exp Cell Res. 1977 Jan;104(1):55–62. doi: 10.1016/0014-4827(77)90068-4. [DOI] [PubMed] [Google Scholar]
- Sheetz M. P., Vale R., Schnapp B., Schroer T., Reese T. Vesicle movements and microtubule-based motors. J Cell Sci Suppl. 1986;5:181–188. doi: 10.1242/jcs.1986.supplement_5.11. [DOI] [PubMed] [Google Scholar]
- Solomon F., Magendantz M. Cytochalasin separates microtubule disassembly from loss of asymmetric morphology. J Cell Biol. 1981 Apr;89(1):157–161. doi: 10.1083/jcb.89.1.157. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Solursh M., Lane M. C. Extracellular matrix triggers a directed cell migratory response in sea urchin primary mesenchyme cells. Dev Biol. 1988 Nov;130(1):397–401. doi: 10.1016/0012-1606(88)90445-9. [DOI] [PubMed] [Google Scholar]
- Sretavan D. W., Reichardt L. F. Time-lapse video analysis of retinal ganglion cell axon pathfinding at the mammalian optic chiasm: growth cone guidance using intrinsic chiasm cues. Neuron. 1993 Apr;10(4):761–777. doi: 10.1016/0896-6273(93)90176-r. [DOI] [PubMed] [Google Scholar]
- Tanaka E. M., Kirschner M. W. Microtubule behavior in the growth cones of living neurons during axon elongation. J Cell Biol. 1991 Oct;115(2):345–363. doi: 10.1083/jcb.115.2.345. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Walter J., Kern-Veits B., Huf J., Stolze B., Bonhoeffer F. Recognition of position-specific properties of tectal cell membranes by retinal axons in vitro. Development. 1987 Dec;101(4):685–696. doi: 10.1242/dev.101.4.685. [DOI] [PubMed] [Google Scholar]