Supplemental Data

Supplemental Data for Rasmussen et al., Developmental Cell 14, pp. 559-569

Document S1. Four Figures and Supplemental Experimental Procedures

Movie S1. Cellular Anatomy of the Group 3 Marginal Cell and pm8 in the Terminal Bulb of the Pharynx
Images are a rotated stack of confocal optical sections through the pharynx of a live, first larval stage animal expressing ref-1::GFP-PM. At this stage, rare animals such as the one shown have expression in all three marginal cell cells in addition to pm8. The middle of each marginal cell retracts from the midline as shown (see Leung et al., 1999), creating a broad, triangular lumen at the junction between the pm6 and pm7 muscle groups (not visible in image); compare with apical junction patterns in Figure 4G.
Movie S2. Expression of Laminin at the mc3V/vpi2V Interface
Time-lapse images of a live embryo expressing lam-1::LAM-1::GFP; the white arrow marks the midline of the epithelial cyst, dorsal is up. Expression is initially at the perimeter of the cyst and in the basal lamina surrounding other embryonic tissues. The red arrow indicates the first appearance of the transepithelial plane of laminin at the mc3V/vpi2V interface. Times indicated are in minutes.
Movie S3. Morphogenesis of pm8
Time-lapse movie of embryo expressing ref-1::GFP-PM in pm8 and mc3V. Expression begins in mc3V much earlier, and is thus brighter, than in pm8; the exposure has been adjusted to make pm8 visible. At the start of the movie, pm8 has largely detached from the dorsal perimeter of the cyst (red lines) but has not entered the ventral epithelium. pm8 migrates into the ventral epithelium on the left side of the midline, then spreads across the midline over finger-like extensions from three mc3 cells; only mc3V is shown in this movie.
Movie S4. Lumenal Channel through pm8
Images are a stack of deconvolved optical sections through a fixed embryo expressing ref-1::GFP-PM in pm8 and mc3V. The embryo is slightly older than shown in Movie S2, and the bulk cytoplasm and nucleus of pm8 are on the ventral side; the pm8 cell body is visible in focal planes throughout the cyst with the mc3V finger through its center. The lumen channel through pm8 appears larger than the single mc3V finger, as the reporter is not expressed in the other two marginal cells that extend fingers into pm8.