Figure 3. Expression and cell-nonautonomous activity of
bam-2. (A) Expression and rescue ability of
bam-2 promoter derivatives driving a full-length
bam-2 cDNA::gfp fusion gene.
bam-2 expression from the VulF vulval cell rescues
bam-2 VC neuron-branching defects. (B to D) Expression pattern of
bam-2 promoter derivatives (ventral views). (B)
bam-2 promoter (~600 bp) exhibits activity in a restricted subset of neurons in the ventral nerve cord and head and tail ganglia. (C)
bam-2 upstream sequence (~5 kb) exhibits additional promoter activity in cells of the somatic gonad. The position of the vulva in (B) and (C) is marked by arrowheads. (D) A fusion of a ~2.4-kb distal
bam-2 upstream sequence and the 600-bp proximal element exhibits promoter activity in additional longitudinal PLN axon tracts (asterisks) and in the VulF vulval cell. Inset shows an enlarged view of VulF. (E and F)
bam-2 is expressed from mid-L4 in VulF (open arrowheads). Lateral views show overlay of VulF GFP fluorescence (delta-xbaIp:
bam-2::gfp) (E) on a differential interference contrast image of the same L4 worm (F). (G and H) delta-xbaIp:
bam-2::gfp expression in the toroidal-shaped VulF cell [(G), ventral view] and in an adult worm [(H), lateral view]. All images except (E) and (F) are flattened confocal Z-series. Anterior is to the left. Scale bars, 10 um.