Fig. 4. Developmental expression of lin-11::GFP (syIs80) in vulval cells. (A,C,E) Nomarski photographs. (B,D,F) lin-11::GFP-expressing vulval cells marked with arrows. Few VC neurons are also visible (star). (A,B) During Pn.px stage, weak GFP fluorescence is detected in the P5.pp and P7.pa cells (arrows in B). (C,D) By Pn.pxx stage, vulval cells express high levels of GFP. The VPC lineage tree has been drawn. In this animal P5.ppx, P6.ppx and P7.pax cells are seen expressing GFP. (E,F) During L4 stage, Pn.pxxx cells express GFP in the P5.p and P7.p progeny. The region occupied by each VPC progeny has been marked. In this focal plane, only a subset of the cells is visible (arrows). Anterior is towards the left. Scale bar: 10 µm.