Fig. 2. Location of Inka cells shown by ETH immunohistochemistry and EGFP expression in the 2eth3egfp transgenic fly line. Red, blue and green colors are for Cy3, DAPI and EGFP, respectively. Scale bars: (C-J) 10 µm. (A) The larval tracheal system and positions of Inka cells (red). (B) Adult tracheal system and positions of the Inka cells (red). Letters correspond to boxed areas in the diagram shown in C-J. (C) Cy3 staining in the late 1st instar using the DrmETH1 antibody. Old intima (arrow) is already separated from new intima. The Inka cell (arrowhead) is located along the main dorsal tracheal trunk at each branchpoint of the transverse connectives. (D) Expression of eth3-egfp transgene in late 3rd instar. The cell expressing EGFP (arrowhead) at a node (arrow, see Fig. 1B) is shown with low intensity transmitted light. (E) Cy3 staining (arrowhead) in the adult stage using the DrmETH1 antibody. (F) Expression of the eth3-egfp transgene (arrowhead) in the adult stage. (G) The eth deletion mutant eth25b Cy3 (late 1st instar) shows no immunohistochemical staining of the Inka cell. The old intima (arrow) is separated from new intima. Open arrowhead indicates location of the epitracheal gland in wild-type flies. (H) Depletion of ETH immunoreactivity in the Inka cell (arrowhead) of wild-type flies (open arrowhead) immediately after ecdysis to early 2nd instar. (I) Immunoreactive Inka cell in the late 3rd instar using an antibody against MasPETH. (J) Inka cell immunoreactivity (arrowheads) in the adult stage using the MasPETH antiserum.
