Basic Fibroblast Growth Factor Elicits Formation of Interstitial Axonal Branches via Enhanced Severing of Microtubules
| Autor: | Mei Liu, Liang Qiang, Wenqian Yu, Joanna M. Solowska, Peter W. Baas |
|---|---|
| Rok vydání: | 2010 |
| Předmět: |
Microtubule-associated protein
Basic fibroblast growth factor tau Proteins Katanin macromolecular substances Hippocampal formation Spastin Hippocampus Microtubules chemistry.chemical_compound Microtubule medicine Animals Phosphorylation Axon Cell Shape Molecular Biology Adenosine Triphosphatases Neurons biology musculoskeletal neural and ocular physiology Biological Transport Articles Cell Biology Axons Rats Cell biology medicine.anatomical_structure nervous system chemistry cardiovascular system biology.protein Fibroblast Growth Factor 2 Microtubule-Associated Proteins |
| Zdroj: | Molecular Biology of the Cell |
| ISSN: | 1939-4586 1059-1524 |
| DOI: | 10.1091/mbc.e09-09-0834 |
| Popis: | This article demonstrates that the augmentation of axonal branching induced by bFGF is explicable on the basis of an enhancement of microtubule-severing, and that three different proteins related to microtubule-severing are affected by treatment of neurons with bFGF. The formation of interstitial axonal branches involves the severing of microtubules at sites where new branches form. Here we wished to ascertain whether basic fibroblast growth factor (bFGF) enhances axonal branching through alterations in proteins involved in the severing of microtubules. We found that treatment of cultured hippocampal neurons with bFGF heightens expression of both katanin and spastin, which are proteins that sever microtubules in the axon. In addition, treatment with bFGF enhances phosphorylation of tau at sites expected to cause it to dissociate from microtubules. This is important because tau regulates the access of katanin to the microtubule. In live-cell imaging experiments, axons of neurons treated with bFGF displayed greater numbers of dynamic free ends of microtubules, as well as greater numbers of short mobile microtubules. Entirely similar enhancement of axonal branching, short microtubule transport, and frequency of microtubule ends was observed when spastin was overexpressed in the neurons. Depletion of either katanin or spastin with siRNA diminished but did not eliminate the enhancement in branching elicited by bFGF. Collectively, these results indicate that bFGF enhances axonal branch formation by augmenting the severing of microtubules through both a spastin-based mode and a katanin-based mode. |
| Databáze: | OpenAIRE |
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