Sans in Fly Development Figure 2. Sans is expressed in tubular organs of the embryo and in ovarian follicle cells. A–E9: Wild-type embryos of the indicated stages hybridized with a Sans-specific antisense RNA probe. A,B,C,D,E: Dorsal views. A9,B9,C9,D9: Lateral views. E9 is a magnification of E showing the Keilin’s organs (arrowheads). F–G: Wild-type ovaries of the indicated stages hybridized with (F,H) a Sans-specific antisense RNA probe or (G) a sense RNA probe. Sans is expressed in follicle cells surrounding the oocyte in stage 10 egg chambers. Anterior is to the left. doi:10.1371/journal.pone.0004753.g002 PLoS ONE | www.plosone.org 3 March 2009 | Volume 4 | Issue 3 | e4753