Picture from Hermann GJ et al. (2000) Development "Left-right asymmetry in C. elegans intestine organogenesis involves a ...."

Figure 2. LIN-12 expression. Embryos at various stages of intestinal development (E4, E8, E16) stained for LIN-12 (top row) and with DAPI (bottom row). Intestinal cells in the left and right halves of the primordium are indicated with white arrows and arrowheads, respectively; the anterior end of the primordium is indicated with black arrowheads for the E8 and E16stages. During the E16 stage, the pattern of LIN-12 expression in the right half of the primordium changes markedly (also see Fig. 4A). Using the numbering system described in Leung et al. (1999), LIN-12 is detected in all of the right primordial cells except numbers 5 and 8 in the early E16stage, then only in numbers 3 and 4 (arrowheads in C; note that the LIN-12 expressing cell at the posterior (bottom) of the embryo is not an intestinal cell), then only in number 4. At the time that the int rings begin to rotate, LIN-12 is not detected in the primordium.