Extended Data Fig. 7: Gradient scaling by recycling: Pentagone.

a, Continuous and monotonic transition from λ ≈ 15 μm (black dashed line) to λ ≈ 27 μm (red dashed line). Left: decay length (λ) versus a parameter b that captures monotonic and continuous changes in k_on, k_off and D₀ as shown in the right. Right: Variations in k_on, k_off and D₀ with b as defined by the equations shown in the plot. Black and red dashed lines indicate initial (small discs) and final (large discs) values for k_on, k_off and D₀. b, Top: expression for the ratio of the recycling to the unbound module (λ_r²/λ_u², see Fig. 1c). Bottom: Sets of parameter values (clouds of points) compatible with all the assays considered in this report in the (k_on, k_off) plane. Isolines for (λ_r²/λ_u² are also shown (see look-up table). The three conditions considered in this work are shown: large discs (average posterior length l = 144 µm in the dataset; left), small discs (average l = 80 µm; centre) and pent² discs (right). These isolines convey the relative importance of the recycling and the unbound modules to the Dpp transport. c, PMAD scaling analysis for control and pentagone mutants. Left, Decay length λ of PMad gradients plotted as a function of posterior compartment length l. Raw and binned data (Bar, s.e.m) are shown together with a linear regression to the raw data. Right, bar plots showing the slopes ϕ of corresponding linear regressions for control (blue) and pentagone mutant experimental conditions (red). Number of biologically independent samples: n = 45 (control) and n = 25 (pent²). ****p-value < 0.00001; two-tailed two sample t-test with unequal variances. Bars, confidence intervals at 95%. d, UAS-GFP-Pentagone expression driven by ap-Gal4. In the right, higher magnification of the area boxed in the image to the left. Scale bars, 10 µm. e, GFP-Pentagone gradient profile in the ventral compartment. The profile is fitted to an exponential function (red) to determine the decay length shown. x, distance from the dorso-ventral boundary. f, eGFP-Dpp^LOP scaling analysis for control and pentagone mutants. Left, Decay length λ of eGFP-Dpp gradients plotted as a function of posterior compartment length l. Raw and binned data (Bar, s.e.m) are shown together with a linear regression to the raw data. Right, bar plot showing the slopes ϕ of corresponding linear regressions from these plots. Control experimental condition (blue) compared to pentagone mutant experimental condition (red). Number of biologically independent samples: n = 157 (control) and n = 63 (pent²). ****p-value < 0.00001; two-tailed two sample t-test with unequal variances. Bars, confidence intervals at 95%. g, Sets of parameter values satisfying the constraints given by all the experimental assays represented in (k_on, k_off), (k_on, D₀) and (k, k_off) planes in the four experimental conditions: eGFP-Dpp^LOP-expressing discs of 144 µm and 80 µm average posterior length and pent² mutant discs of 130 µm and 85 µm average posterior length. h, Stacked bar chart showing the relative contribution of the different modules to λ² (described in Fig. 1e,f) in the four experimental conditions in e compared to the theoretical values of parameters in the extracellular diffusion (ExD) and transcytosis regimes of transport (Tr). i, Average extracellular fraction in control discs of 144 µm and 80 µm average posterior length and pent² mutant discs of 130 µm and 85 µm average posterior length. Box plot represents the minimum and the maximum, median, 25^th and 75^th percentile. n, number of biologically independent samples. j, Confocal images of PentGFP from the endogenous gene in discs of different sizes. Scale bar, 10 µm. Dotted lines, contour of discs. k, PentGFP average intensity in its expression domain as a function of the squared posterior length of the wing disc; Black, binned data. Orange dots, raw data. Bars, s.e.m. Vertical boxes indicate posterior width sizes l = 144 µm (orange) and l = 80 µm (blue).

Source data