Vinculin marks basal junctions whereas ZO-1 marks both apical and basal junctions. (A) Structured-illumination microscopy of synaptopodin and ZO-1. A z-stack is shown in X-Y, Y-Z, and X-Y axes. Left panel shows apical stress fibers and contractomeres on the apical plane. Right panel shows basal stress fibers inserted at basal junctions. Attachment sites for synaptopodin apical stress fibers are circled. Arrows on Y-Z axis point to apical and basal planes. Scale bar is 5 μm. (B) Live-cell structured-illumination microscopy of synaptopodin and vinculin. Vinculin marks the basal junction where basal stress fibers are inserted. Inset shows synaptopodin stress fibers inserted at vinculin-decorated focal adhesions. Graph shows a line scan of the yellow arrow along a basal stress fiber (inset). Synaptopodin has periodic organization at the stress fiber. Scale bar is 5 μm. Inset scale bar is 1 μm.