Spindle Assembly in Control Spermatocytes
mediaposted on 30.12.2011, 10:47 by Elena Rebollo, Salud Llamazares, José Reina, Cayetano Gonzalez
Contribution of Noncentrosomal Microtubules to Spindle Assembly in Drosophila Spermatocytes. PLoS Biol 2(1): e8. doi:10.1371/journal.pbio.0020008 Copyright: © 2004 Rebollo et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Inhibition of centrosome migration back from the plasma membrane in Drosophila spermatocytes offers an unprecedented opportunity to assay centrosome-independent microtubule polymerisation during spindle assembly in the cells of a living animal that contain centrosomes. Therefore, we decided to follow microtubules by time-lapse confocal microscopy in asp and colcemid-treated cells that expressed a GFP–α-tubulin fusion, as they went through meiosis. At the onset of prometaphase, the NE becomes fenestrated, but does not disappear in Drosophila (Tates 1971; Stafstrom and Staehelin 1984; Church and Lin 1985). This partial NEB can be readily identified by the sudden entry of GFP–α-tubulin into the nuclear region (Figure 2, timepoint 0; Video S2). In control cells, microtubule polymerisation and organisation are largely concentrated around the centrosomes (Church and Lin 1982; Cenci et al. 1994). Consequently, the abundance of these microtubules makes it extremely difficult to determine the possible contribution of any centrosome-independent microtubule polymerisation activity to spindle assembly (Figure 2, control, 10 min to 32 min; Video S2).