Fig. 4. Dystroglycan is required for the establishment of oocyte polarity. (A) Dg germline clones are usually arrested at around stage 6 of oogenesis (arrow, a Dg²⁴⁸ germline clone is smaller than the two neighboring egg chambers). (B,C) Nod-ß-Gal (red), a marker that co-localizes with the MTOC in early oocytes, moves from the anterior of the oocyte (red in B) to the posterior and stays there until stage 6 (arrow in C). (D,E) In Dg²⁴⁸ germline clones, Nod-ß-Gal (red) is frequently mislocalized (arrows). (F) ORB (red), is also localized to the posterior of the oocyte at stages 2-6 (arrow). (G) In a Dg³²³ germline clone, ORB (red) is mislocalized (surrounds the oocyte nucleus, arrow) or undetectable (not shown). (H,I) DG is required for the enrichment of the actin cytoskeleton in the oocyte (marked by an asterisk). In the wild-type oocyte (H), actin (red; white in inset) is enriched at the posterior of the oocyte (arrows). In a Dg³²³ germline clone (I), actin (red; white in inset) failed to be enriched at the posterior of the oocyte (arrow), and ring canals accumulate tightly in the anterior of the oocyte (arrowhead). (J) Schematic drawing depicting the anterior-to-posterior migration of MTOC in an early wild-type oocyte. This movement is defective and correlates with defect in posterior enrichment of actin in Dg germline clones (K).