Dataset Information

Comparison of slow and fast neocortical neuron migration using a new in vitro model.

ABSTRACT:

Background

Mutations, toxic insults and radiation exposure are known to slow or arrest the migration of cortical neurons, in most cases by unknown mechanisms. The movement of migrating neurons is saltatory, reflecting the intermittent movement of the nucleus (nucleokinesis) within the confines of the plasma membrane. Each nucleokinetic movement is analogous to a step. Thus, average migration speed could be reduced by lowering step frequency and/or step distance.

Results

To assess the kinetic features of cortical neuron migration we developed a cell culture system that supports fiber-guided migration. In this system, the majority of fiber-apposed cells were neurons, expressed age-appropriate cortical-layer specific markers and migrated during a 30 min imaging period. Comparison of the slowest and fastest quartiles of cells revealed a 5-fold difference in average speed. The major determinant of average speed in slower cells (6-26 microm/hr) was step frequency, while step distance was the critical determinant of average speed in faster cells (>26 microm/hr). Surprisingly, step distance was largely determined by the average duration of the step, rather than the speed of nucleokinesis during the step, which differed by only 1.3-fold between the slowest and fastest quartiles.

Conclusion

Saltatory event frequency and duration, not nucleokinetic speed, are the major determinants of average migration speed in healthy neurons. Alteration of either saltatory event frequency or duration should be considered along with nucleokinetic abnormalities as possible contributors to pathological conditions.

SUBMITTER: Nichols AJ

PROVIDER: S-EPMC2440755 | biostudies-literature | 2008 Jun

REPOSITORIES: biostudies-literature

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Publications

Comparison of slow and fast neocortical neuron migration using a new in vitro model.

Nichols Anna J AJ Carney Laurel H LH Olson Eric C EC

BMC neuroscience 20080605

<h4>Background</h4>Mutations, toxic insults and radiation exposure are known to slow or arrest the migration of cortical neurons, in most cases by unknown mechanisms. The movement of migrating neurons is saltatory, reflecting the intermittent movement of the nucleus (nucleokinesis) within the confines of the plasma membrane. Each nucleokinetic movement is analogous to a step. Thus, average migration speed could be reduced by lowering step frequency and/or step distance.<h4>Results</h4>To assess ...[more]

PMID: 18534012

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Dataset Information

Comparison of slow and fast neocortical neuron migration using a new in vitro model.

Background

Results

Conclusion

Publications

Comparison of slow and fast neocortical neuron migration using a new in vitro model.

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