Fig. 3: 3D structure of actively growing seta.
From: Structural evidence for extracellular silica formation by diatoms
a A low-magnification cryoTEM image of vitrified C. tenuissimus cells. The thick cell bodies are indicted with (*). The middle cell has two fully formed setae (green arrowheads) and two shorter, presumably forming, setae (purple arrowheads). b A high-magnification cryoTEM projection image of the tip of a forming seta. c, d 2D orthogonal views through the 3D reconstructed tomogram of a forming seta. e Volume rendering of the different components of a growing seta: The microtubule is in green, intracellular vesicles in yellow, cell membrane in red, silica cell wall in blue, and external layer in gray. f 3D view of the silica cell wall and external layer only. g, h 3D views of the silica cell wall and cell membrane only. i Zoom in on a slice through a 3D data set, demonstrating the structural difference between the lipid bilayer membrane of the cell (in red) and the envelope external to the cell wall (yellow arrowhead); silica is indicated by (*). See Supplementary Movie 1 for an animation of the 3D reconstruction.
