Conserved and novel enhancers in the Aedes aegypti single-minded locus recapitulate embryonic ventral midline gene expression
Fig 4
Cell-type activity of the 5P3F enhancer in transgenic Drosophila embryos.
(A) Cartoon of the midline cell lineages at the midline primordium stages (adapted from [68]). Cells of the MP4 equivalence group are shown in shades of blue. Cells with heavy outlining express Engrailed. (B) Co-labeling of the 5P3F reporter (magenta) with Nubbin (Nub; green) at stage 13 shows that 5P3F is not active in H-cell or H-cell-sib. (C) Co-labeling with Slit (Sli; green) indicates 5P3F activity in posterior midline glia, shown in dissected embryos at stage 16. (D) 5P3F activity is both in and adjacent to cells expressing Mab 22C10 (Futsch; green), which marks the mVUMs, shown here at stage 16. (E-G) Sagittal sections showing co-labeling of the 5P3F reporter (magenta) with Engrailed (En; green) at stage 13. 5P3F reporter gene expression is observed in the mVUMs (white arrowheads), iVUMs (yellow arrowheads), MNB and progeny (yellow arrow), and posterior midline glia (PMG; thick white arrow). Not all of the PMG are expressing the reporter (thin white arrows). (H) Cartoon of the stage 13 midline (adapted from [69]). (I) Co-labeling of the 5P3F reporter (magenta) with Engrailed (En; green) at stage 11 (ventral view). All reporter-gene expressing cells are positive for En with the exception of a single anterior cell (arrow), likely one of the MNB progeny. Embryos in B, C, D, and I show a ventral section while E-G are sagittal sections; all embryos have anterior to the left.