Fig. 3: 4Pi-SIM revealed the 3D architecture of the ER, Golgi apparatus and PM.

a, 4Pi-SIM image (maximum intensity projection) of immunolabeled ER in a fixed COS-7 cell (Supplementary Video 6). b, Left: magnified 3D rendering of the boxed region labeled ‘b’ in a. Right: the y–z and x–z cross-sections along the corresponding dashed lines, taken in the 3D- and 4Pi-SIM modes. The arrowheads indicate the positions where the axial intensity profiles were taken. The distances between peaks were obtained after fitting with multiple Gaussian functions. c, Left: magnified 3D rendering of the boxed region denoted ‘c’ in a. Right: the y–z and x–z cross-sections along the corresponding dashed lines, taken in the the 3D- and 4Pi-SIM modes. d–f, 3D renderings of the immunolabeled Golgi apparatus in fixed HeLa cells imaged with 4Pi-SIM (Supplementary Video 7). In d–f, antibodies labeled the cis-Golgi (GM130), medial-Golgi (giantin) and trans-Golgi (Golgin97). Insets: maximum intensity projection in the x–y view. Bottom: magnified cross-sections of 3D- and 4Pi-SIM along the dashed lines in the corresponding insets. g, A 3D rendering of the immunolabeled plasma membrane (WGA-Alexa Fluor 488) in a fixed HeLa cell imaged with 4Pi-SIM (Supplementary Video 8). h, Maximum intensity projection of g in the x–y view, and cross-sections along the dashed lines denoted (1), (2) and (3). Colors represent depth from coverslip, denoted by the color bars. Scale bars: 5 μm (a; projection in d, e, f, h); 1 μm (b (1,2), c (1,2), d(1,2), e (1,2), f (1,2), h (1,2,3)). The thickness of all cross-section slices is 30 nm. Representative results are shown from three to six independent experiments.