||P.18858 left column top paragraph:"Eqn 6 implies that the shape of the anterior proliferation profile depends on the shape of the signaling profile. [Investigators] tested this by simultaneously fitting signaling and proliferation profiles, using Eqn 6 to constrain the fit functions (see the Materials and methods in the supplementary material). This simultaneous fit performs very well, for both P-Mad and Hairy signaling profiles (R^2=0.96 supplementary material Fig. S1A), but slightly overestimates the distance between the peaks of P-Mad or Hairy profiles and the peak of the PH3 profile. This finding may indicate the existence of a delay between the commitment to undergo mitosis and the onset of PH3 expression, i.e. the onset of PH3 expression happens later and is therefore shifted posteriorly compared with the mitotic-decision-making event. [Investigators] estimate this time delay to be about 2 h (R^2=0.97 Fig. 2F, supplementary material Table S2). Taking this into account, [investigators] find that α is approximately equal to 60% (Fig. 2F, supplementary material Table S2). Strikingly, in wild-type eye discs, the relative levels of Hairy and P-Mad are proportional to a large extent (Fig. 2D), i.e. although their amplitudes are different (supplementary material Fig. S1C), the shape of the relative signaling profiles is very similar (Fig. 2B-C), and as a consequence, the value of α is similar for both (αPMad=0.57±0.19, αHairy=0.71±0.25 supplementary material Table S2)." See note beneath table S2. Morphogen Dpp="one of several Drosophila factors controlling morphogenetic growth, in the developing eye."