Fig. 4: SEM volume imaging of E. gracilis.
From: Reduction of SEM charging artefacts in native cryogenic biological samples
E. gracilis imaged at 52° with respect to the FIB milled sample plane using 100 ns dwell time ×100 repetitions. A 1600 µm³ volume in focus aligned and subject to manual segmentation of the region of interest. A, C–G Images after background removal (see “Methods”) to assist segmentation. For A, C–G, the number in the upper corner is the z-location within the volume. A Membranes of the degradation compartment segmented (red line) and content (blue line). Scale bar: 2 µm. B Density (ratio of the content volume within the degradative compartment) as a function of the volume of the degradative compartment showing the presence of four unrelated populations (quadrant count ratio = 0.037). C–E Enlarged panels from the coloured boxes in (A), highlighting the membrane deformation of organelles in close proximity to the degradation compartment (DC) or empty vesicles and other organelles including mitochondria (m) and chloroplast (C) or an absence of contact with, for example, the Golgi apparatus (GA). The limits of these contacts are indicated by a black arrow. Scale bars: 500 nm (C), 250 nm (D–E). F, G Enlarged panels of the eyespot and 3D segmentation, proximal to the reservoir (R). Compartments in proximity (V: vesicle, C: chloroplast). Scale bar: 250 nm.
