Interkinetic nuclear movements promote apical expansion in pseudostratified epithelia at the expense of apicobasal elongation
Fig 4
INM opposes apical contractility.
Same simulations as in Fig 3 but with contractile apical-apical springs with INM (black and brown curves) or without INM (red curve), with constant cell number (see S2 Movie). A, Apicobasal length of the PSE (AB) and mean nuclear position along the AB axis, expressed in micrometers. B, Number of layers of nuclei along the AB axis. C, straightness of apical domain (net distance between the first and last apical point divided by the actual distance between these two points). D, Position of mitoses along AB axis, 1 being apical. E-G, net width of apical (magenta), nuclear (black) and basal (cyan) domains of the PSE over time. For each domain, the distance between the first and last point along the lateral axis is computed and its evolution plotted over time. Note that apical contractility reduces the width of the apical domain (panel 4E, arrow), whereas introducing INM opposes apical contractility (panel 4G, arrow; red curve in G is higher than in E). Each simulation was performed over 480 iterations (48h of biological time) for 10 repetitions. Each curve represents the mean value of each dataset for the parameter plotted. Box and whiskers plot: the box extends from the 25th to the 75th percentile; the whiskers show the extent of the whole dataset. The median is plotted as a line inside the box.