Fig. 8. smp-1 and smp-2 expression patterns visualized with gfp transcriptional reporters during embryogenesis. DIC (left) and GFP (right) images of the same embryo. (A,B) The expression pattern of smp-1::gfp can be initially observed at approximately 150 minutes in four cells of the E lineage and later at about 250 minutes of development spread to eight cell of the same lineage. (C,D) At the time of ventral enclosure, the leading edge epidermal cells and the muscle lineage start to express smp-1::gfp. (E,F) In the comma stage, muscle precursors and other cells in the head express smp-1::gfp. (G,H) Initial embryonic expression of smp-2::gfp is observed at the twofold stage in pharyngeal (arrows) and intestinal (arrowheads) cells. These cells were identified using SIMI BioCell CD ROM^TM (Schnabel et al., 1997).