Figure 6.

Electron micrographs of in situ immunogold-labeled HSS in roots of S. vernalis. A, Two cells of the endodermis (En) with the casparian strip (Ca) as incrustation in the radial cell wall. The endodermis cells are accompanied by cells of the pericycle (Pc) and the cortex parenchyma (Co). Gold label is only found in the endodermis and the adjacent cortex cells, but no label is detectable in the pericycle. B, Cell junction of two endodermis cells (En; casparian strip at bottom right) with a cell of the pericycle (Pc). C, Detail of labeled cells that show the label exclusively in the cytoplasm. All detectable organelles are devoid of any label (at the right is an intercellular space, Ic).