Fig. 6: Endocytosis in subapical cells.

a FM4-64 staining of hyphal cells, co-stained with the vacuole marker DCFDA. Note that the dye reaches vacuolar membranes due to endocytic uptake. Scale bar = 5 µm. b Endocytic actin patches, labelled with Lifeact-TreGFP, at the subapical region of the 1^st cell and in the 2^nd cell. The edge of the cell is shown in red; the 1st septum is stained using Calcofluor White (blue). Scale bar = 2 µm. c Contrast-inverted image of actin patches in the 2^nd cell. Time in seconds between images is shown in the upper right corner. Note that patch dynamics indicate active endocytosis. Scale bar = 1 µm. d Contrast-inverted kymographs showing the dynamic behaviour of an actin patch at the plasma membrane (left panel: side view; right panel: top view). The patch appears at the plasma membrane and is stationary during endocytic vesicle (Formation). Shortly after appearance, the actin patch shows diffusional motility (transition indicated by open arrowheads) and occasionally undergoes rapid directed transport (closed arrowhead). Shortly after this, the actin patch disappeared. Horizontal scale bars = 1 µm; vertical scale bars = 3 s. e Contrast-inverted kymographs showing the dynamic behaviour of an actin patch at the plasma membrane in the apical and all subapical cells. Data were taken 20 µm behind the tip or septa. Horizontal scale bar = 3 µm; vertical scale bar = 5 s. See also Supplementary Movie 12. f Distribution of actin patches, labelled with Lifeact-TreGFP, in hyphae of T. reesei. Sample size n = 13- cells for 1^{st (tip)}, 1^{st (centre)}, 2^nd, 3^rd, 4^th, 5^th, 6^th and Sample size n = 16 for 1^{st (end)} from 2–3 independent experiments. Results shown in (a–e) were confirmed in 2 independent experiments. Data in (f) show mean ± SEM. Data in (a) were obtained from growing hyphae. All data are provided in the Source Data file.