Fig. 11. Time-lapse analysis of glial cell division. (A) Time-lapse analysis of a repo-tauGFP GPI: (a-f) proximodistal extensions keep elongating (arrowheads), whereas the others prune back (asterisks). (B) Time-lapse sequence of a GPI division using repo-ncGFP. (a-d) Glial extensions rapidly prune back so that the cell adopts an almost round shape (d). Upon cell division (e), the GPIIs rapidly send out novel extensions (f-h). (C) Microtubule reorganisation at division. Confocal projections, illustrating a GPI division (repo-tauGFP). (a-c) Colour coding allows labelling quantification and thereby the identification of centrosomes as red spots (highest GFP levels). (b,c) Centrosomes migrate and position themselves perpendicular to the orientation of division. (d-f) GFP reveals the mitotic spindle, which undergoes rotation, so that division takes place along the proximodistal axis (g,h). (D) Time-lapse sequence showing that GPIIs of the same sensory organ divide synchronously. Glial nuclei are indicated by asterisks. Scale bars: 10 µm (A,C); 20 µm (B); 30 µm (D).