Figure 2

Socs36E and Socs44A are expressed in different spatio-temporal patterns. The embryonic expression patterns of upd and Socs36E are dynamic from early blastoderm throughout embryogenesis [see 28, 29 and Fig. 3]. Socs44A expression is not detected until very late stages in the trachea (A). Although such staining can be artifactual, sense strand probe never showed any staining (B). In the ovary, upd is expressed specifically in the polar follicle cells at each end of the chamber (C). Socs36E expression encompasses the anterior and posterior follicular epithelium, with highest expression at the poles (D). This is consistent with activation of Socs36E transcription due to reception of the Upd ligand which is secreted from the polar follicle cells and diffuses toward surrounding cells. Socs44A expression is restricted to the germline and only during later stages of oogenesis (E)