Dynamic instability of native microtubules from squid axons is rare and independent of gliding and vesicle transport.
Dynamic instability characterizes the steady-state behavior of microtubules in vitro whereby polymer mass remains constant, while individual microtubules in the population may either grow or shrink. Video-enhanced contrast light microscopy was used to directly observe dynamic length changes in native, MAP-containing microtubules from squid axoplasm. We wanted to determine whether dynamic instability characterizes the steady-state behavior of axoplasmic microtubules in vitro. The lengths of a representative population of over 400 microtubules were analyzed. "Dynamic" microtubules were found to represent about 2% of the population. This observation is different from that described for cultured cells or microtubules assembled from PC-purified tubulin where most microtubules were either growing or shrinking.
Seitz-Tutter
D
D
Institut für Zoologie, Technische Universität München, Garching, Federal Republic of Germany.
Langford
G M
GM
Weiss
D G
DG
D000818:Animals; D001370:Axonal Transport; D001369:Axons / Q000502:physiology / Q000648:ultrastructure*; D049832:Decapodiformes; D004591:Electrophoresis, Polyacrylamide Gel; D008869:Microtubule-Associated Proteins / Q000032:analysis; D008870:Microtubules / Q000502:physiology* / Q000648:ultrastructure; D014743:Videotape Recording
D008869:Microtubule-Associated Proteins