Fig. 3. Microtubule organization in sktl mutant oocyte. WT (A,C,E,G,I,K,N,O) and sktl^2.3 mutant (B,D,J,L,M) Drosophila germline clones and sktl^2.3/sktl⁵ mutant egg chambers (F,H,P,Q). (A-D) Microtubule (MT) network detected with Khc antibody. In stage 8 sktl^2.3 oocytes, MT network organization is not affected (compare B with A). However, in stage 10 sktl^2.3 oocytes, MT organization is disrupted (compare D with C). MT bundles appear to project from the mislocalized nucleus towards the center of the cytoplasm (arrowheads in D). (E,F)Khc-β-gal (red) and DNA (green) staining. In sktl^2.3/sktl⁵ oocytes, the posterior pool of Khc-β-gal is lost and it accumulates in the anterior part of the oocyte (F). The inset in F shows Khc-β-gal staining alone. (G,H) Dmn-GFP. In sktl^2.3/sktl⁵ oocytes, the posterior pool of Dmn-GFP is lost and an accumulation is found in the most anterior part of the cytoplasm (H). However, cortical- and nuclear-associated localization are unaffected, even when the nucleus is mislocalized. (I,J) In both mutant and WT, the centrosome component DPLP (red) is detected around the oocyte nucleus and as a dot close to it (arrowhead). The dots surrounding the oocyte correspond to the centrosomes of the follicular cells. (K-M) Projections of confocal sections from oocytes immunostained with Spn-F antibody revealing the minus ends of the MTs. Spn-F is found mislocalized in a characteristic cortical ring close to the mislocalized nucleus in stage 10 sktl^2.3 oocytes (compare M with K), but not in stage 8 (L). (N-Q)MT detection by anti-Khc. WT (N) and sktl^2.3/sktl⁵ (P) oocytes showing complete depolymerization of MTs after 30 minutes of cold shock. (O,Q) WT and mutant oocytes after a 10-minute recovery at 25°C. MTs regrow from the misplaced nucleus (arrowheads in Q). Asterisk, nucleus.