Axon extension occurs independently of centrosomal microtubule nucleation.
Microtubules are polymeric protein structures and components of the cytoskeleton. Their dynamic polymerization is important for diverse cellular functions. The centrosome is the classical site of microtubule nucleation and is thought to be essential for axon growth and neuronal differentiation--processes that require microtubule assembly. We found that the centrosome loses its function as a microtubule organizing center during development of rodent hippocampal neurons. Axons still extended and regenerated through acentrosomal microtubule nucleation, and axons continued to grow after laser ablation of the centrosome in early neuronal development. Thus, decentralized microtubule assembly enables axon extension and regeneration, and, after axon initiation, acentrosomal microtubule nucleation arranges the cytoskeleton, which is the source of the sophisticated morphology of neurons.
Stiess
Michael
M
Independent Junior Research Group Axonal Growth and Regeneration, Max Planck Institute of Neurobiology, Am Klopferspitz 18, 82152 Martinsried, Germany.
Maghelli
Nicola
N
Kapitein
Lukas C
LC
Gomis-Rüth
Susana
S
Wilsch-Bräuninger
Michaela
M
Hoogenraad
Casper C
CC
Tolić-Nørrelykke
Iva M
IM
Bradke
Frank
F
D000818:Animals; D000941:Antigens / Q000378:metabolism; D001369:Axons / Q000502:physiology* / Q000648:ultrastructure; D019771:Axotomy; D018385:Centrosome / Q000502:physiology* / Q000648:ultrastructure; D006624:Hippocampus / Q000166:cytology*; D051379:Mice; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D008870:Microtubules / Q000378:metabolism* / Q000648:ultrastructure; D009416:Nerve Regeneration; D055495:Neurogenesis; D009474:Neurons / Q000502:physiology* / Q000648:ultrastructure; D051381:Rats; D014404:Tubulin / Q000378:metabolism
D000941:Antigens; D008869:Microtubule-Associated Proteins; D014404:Tubulin; C086178:pericentrin