Figure 1. Spatio-Temporal Expression of
plx-2 Translational Reporter in the Developing Male Tail. (A) An identical sublineage generates the three cells of each sensory ray in the male tail, including two neurons, RnA, a cell death (X) and RnB, the Rnst structural support cell for the neurons (cells Rn.aaa, Rn.apa, and Rn.app, respectively), and a hypodermal cell (Rn.p).(B-E) evIs168[
plx-2::GFP] translational reporter expresses prior and throughout male tail and ray morphogenesis. Anterior is left and panels are lateral views except where noted. The translational reporter labels the surface of cells, unlike the transcriptional reporter, which labels the cytoplasm. (B) evIs168 expresses in alternating Rn ray precursor cells of rays 1, 3, 5, and 7 (open arrowheads) in L3 larvae prior to sensory ray sorting. A phasmid neuron (Ph) is a reference point (closed arrowhead). (C)
plx-2::GFP continues to express in a subset of Rn.a descendants (open arrowheads) in the early L4 larval stage when sensory ray sorting occurs. (D and E, dorsal view) evIs168 expresses in the Rnst ray structural support cells. (D) shows the cell bodies and (E) the outline (closed arrowheads) of an Rnst cell (same animal as [D]) with no GFP-expressing neuron inside.(F) Lateral view of surface of male tail by D.I.C. optics showing the sensory papillae openings into the cuticle. Rnst cells of rays 3, 5, 6, and 7 express (ray 3 is out of focus).(G) evIs168 expression is ring-like because the Rnst support cells encircle the sensory endings of RnA and RnB and simultaneously connect to the epidermis.(H and I) D.I.C. and
ram-5::gfp reporter expression in Rnst cells for rays 1-9 in a wild-type male tail.(J-M) D.I.C. and
ram-5::gfp reporter expression in Rnst cells for rays 1-9 in 2
mab-20(
ev574) male tails. In ray fusions, the Rnst cells from neighboring rays are clearly aggregated (open arrowheads), while Rnst processes can be seen extending away from their aggregated endings (closed arrowheads) and can be traced to their cell bodies. These Rnst endings are probably not fused (see Supplemental Figure S6 at
http://www.developmentalcell.com/cgi/content/full/6/3/383/DC1).