Fig. 2. shark expression is altered in bwk mutants. In situ hybridization of egg chambers probed with antisense shark RNA in Canton S (A,C,C') and in bwk^151/8482 egg chambers (B,D,D'). (A) In early oogenesis, shark RNA is expressed in all tissues, with higher levels in the germline. (C) Surface view. At stage 10, shark RNA accumulates in darkly staining concentrations at the periphery of nurse cells. Boxed area shows RNA foci associated with stretch-cell nuclei. Faint expression in the columnar cells over the oocyte is also seen. (C') Magnified view of the boxed area in C. Arrowheads indicate stretch cell nuclei. (B) In bwk egg chambers, the RNA appears more diffuse, although levels are comparable with wild type. (D) At stage 10, the concentrated RNA foci at the anterior are greatly reduced (compare with C). (D') Magnified view of area outlined by blue box in D. Arrowhead indicates stretch cell nucleus. Scale bars: 100 µm.