Fig. 5: Consecutive asymmetric divisions in terms of cell volume lead to a disproportionately large size of the excretory cell, ABplpappaap.

A The “H”-shaped excretory cell labeled by GFP (left) or its merge with differential interference contrast microscopy (DIC) (right) in an adult. B Top: quantification of volume changes over embryogenesis for the excretory cell and all the progeny of its great-grandmother, ABplpapp. The graph shows the average cell volumes (line) and their standard deviations (shaded area) for the excretory cell and its progenitors from eight wild-type embryos in red, and for their sister cells in green. Bottom: quantification of volume change over embryogenesis for all cells derived from AB (blue) and E (gray) with that for the excretory cell and its progenitors (red, same data as in upper row). The time of ABplpapp’s birth is used as the reference point (time zero). C Comparison of morphological changes between the excretory cell’s grandmother ABplpappa with Notch signaling (middle) and its sibling with substantially weaker or no effective Notch signaling (top), in a wild-type embryo, or the ABplpappa cell in a perturbed embryo with RNAi against lag-1 (bottom). Note the directional size asymmetry in the division of ABplpappa (middle) in contrast to its sister (top), and its perturbed state in embryos with RNAi against lag-1 (bottom). \({T}_{{{{\rm{C}}}}}\) denotes the last time point of cytokinesis. Source data are provided as a Source Data file.