Figure 11. Minimal Spanning Trees (MSTs) adhering to wiring optimization rules do not recapitulate the morphological features of individual STG neurons.
Synthetic MSTs adhering to the wiring cost rule: total cost = wiring cost + bf * path length cost (where bf = balancing factor) were generated using the TREEs toolbox (described in Materials and methods and by Cuntz et al., 2010). (A) An example of four synthetic minimal spanning trees (right) with varying bf values generated from the first branch point (location indicated as red circle on actual skeleton of an LP neuron; left) as the root. The carrier points (blue) were randomly generated from points uniformly distributed across the elliptical volume approximating the actual volume occupied by the neuron. The number of carrier points was tuned such that the MSTs had branch point number within 20% of the actual neuron’s branch point number (Table 3). Scale bars apply to skeleton, carrier point, and MST plots. (B) Morphological features of synthetic trees generated with bf values between 0.1 and 0.6 plotted against measurements from four actual STG neurons (one of each type, indicated on left and by color). Features of actual neurons are shown with black lines, whereas synthetic neurite tree data are plotted in the color scale described in the key for each neuron. Total wiring lengths, branch order distributions, neurite length distributions, and tortuosity distributions were calculated excluding axons for all synthetic and actual neurite trees. Branch order, neurite length, and tortuosity distributions were normalized to the maximum within each data set (for each bf value and actual neurite tree) for direct comparison of distributions despite varying neurite path counts.
Figure 11—figure supplement 1. Minimal spanning trees (MSTs) adhering to wiring optimization rules do not recapitulate the morphological features of gastric mill (GM) neurons.
MSTs were generated using the TREEs toolbox (described in Materials and methods and by Cuntz et al., 2010) and adhered to the wiring cost rule: total cost = wiring cost + bf * path length cost (where bf = balancing factor). For each of four GM neurons, MSTs with bf values between 0 and 0.6 were generated from the first branch point as the root. The terminal tip coordinates were randomly generated from points uniformly distributed across the elliptical volume approximating the actual volume occupied by the neuron (as in Figure 11A). The number of terminal tip coordinates was tuned for each neuron, such that the MSTs had branch point numbers within 20% of the actual neuron’s branch point number. A–D present plots comparing morphological features (total wiring, branch point (pts), neurite lengths, branch orders, and tortuosities) of the MSTs to those measured in each of four actual STG neurons. In scatter plots (left), thick lines are indicative of the total wiring or branch point number of the actual neuron, whereas colored points correspond with these metrics for the MSTs of the bf value (indicated in key). Thin black lines indicate 20% above or below the actual neuron’s total wiring or branch point number. For histograms (right), measurements from actual neurons are shown with black lines, whereas synthetic MST data are plotted in the color scale described in the key. Branch order, neurite length, and tortuosity distributions were normalized to the maximum within each data set (for each bf value and actual neurite tree) for direct comparison of distributions despite varying neurite path counts. It is evident that not one bf value capitulates all features of the actual GM neurons.
Figure 11—figure supplement 2. Minimal spanning trees (MSTs) adhering to wiring optimization rules do not recapitulate the morphological features of lateral gastric (LG) neurons.
MSTs were generated using the TREEs toolbox (described in Materials and methods and by Cuntz et al., 2010) and adhered to the wiring cost rule: total cost = wiring cost + bf * path length cost (where bf = balancing factor). For each of four LG neurons, MSTs with bf values between 0 and 0.6 were generated from the first branch point as the root. The terminal tip coordinates were randomly generated from points uniformly distributed across the elliptical volume approximating the actual volume occupied by the neuron (as in Figure 11A). The number of terminal tip coordinates was tuned for each neuron, such that the MSTs had branch point numbers within 20% of the actual neuron’s branch point number. A–D present plots comparing morphological features (total wiring, branch point (pts), neurite lengths, branch orders, and tortuosities) of the MSTs to those measured in each of four actual STG neurons. In scatter plots (left), thick lines are indicative of the total wiring or branch point number of the actual neuron, whereas colored points correspond with these metrics for the MSTs of the bf value (indicated in key). Thin black lines indicate 20% above or below the actual neuron’s total wiring or branch point number. For histograms (right), measurements from actual neurons are shown with black lines, whereas synthetic MST data are plotted in the color scale described in the key. Branch order, neurite length, and tortuosity distributions were normalized to the maximum within each data set (for each bf value and actual neurite tree) for direct comparison of distributions despite varying neurite path counts. It is evident that not one bf value capitulates all features of the actual LG neurons.
Figure 11—figure supplement 3. Minimal spanning trees (MSTs) adhering to wiring optimization rules do not recapitulate the morphological features of lateral pyloric (LP) neurons.
MSTs were generated using the TREEs toolbox (described in Materials and methods and by Cuntz et al., 2010) and adhered to the wiring cost rule: total cost = wiring cost + bf * path length cost (where bf = balancing factor). For each of four LP neurons, MSTs with bf values between 0 and 0.6 were generated from the first branch point as the root. The terminal tip coordinates were randomly generated from points uniformly distributed across the elliptical volume approximating the actual volume occupied by the neuron (as in Figure 11A). The number of terminal tip coordinates was tuned for each neuron, such that the MSTs had branch point numbers within 20% of the actual neuron’s branch point number. A–D present plots comparing morphological features (total wiring, branch point (pts), neurite lengths, branch orders, and tortuosities) of the MSTs to those measured in each of four actual STG neurons. In scatter plots (left), thick lines are indicative of the total wiring or branch point number of the actual neuron, whereas colored points correspond with these metrics for the MSTs of the bf value (indicated in key). Thin black lines indicate 20% above or below the actual neuron’s total wiring or branch point number. For histograms (right), measurements from actual neurons are shown with black lines, whereas synthetic MST data are plotted in the color scale described in the key. Branch order, neurite length, and tortuosity distributions were normalized to the maximum within each data set (for each bf value and actual neurite tree) for direct comparison of distributions despite varying neurite path counts. It is evident that not one bf value capitulates all features of the actual LP neurons.
Figure 11—figure supplement 4. Minimal spanning trees (MSTs) adhering to wiring optimization rules do not recapitulate the morphological features of pyloric dilator (PD) neurons.
MSTs were generated using the TREEs toolbox (described in Materials and methods and by Cuntz et al., 2010) and adhered to the wiring cost rule: total cost = wiring cost + bf * path length cost (where bf = balancing factor). For each of four PD neurons, MSTs with bf values between 0 and 0.6 were generated from the first branch point as the root. The terminal tip coordinates were randomly generated from points uniformly distributed across the elliptical volume approximating the actual volume occupied by the neuron (as in Figure 11A). The number of terminal tip coordinates was tuned for each neuron, such that the MSTs had branch point numbers within 20% of the actual neuron’s branch point number. A–D present plots comparing morphological features (total wiring, branch point (pts), neurite lengths, branch orders, and tortuosities) of the MSTs to those measured in each of four actual STG neurons. In scatter plots (left), thick lines are indicative of the total wiring or branch point number of the actual neuron, whereas colored points correspond with these metrics for the MSTs of the bf value (indicated in key). Thin black lines indicate 20% above or below the actual neuron’s total wiring or branch point number. For histograms (right), measurements from actual neurons are shown with black lines, whereas synthetic MST data are plotted in the color scale described in the key. Branch order, neurite length, and tortuosity distributions were normalized to the maximum within each data set (for each bf value and actual neurite tree) for direct comparison of distributions despite varying neurite path counts. It is evident that not one bf value capitulates all features of the actual PD neurons.