Summary
Numerous plasmodesmata occur in the walls between the secretory cells ofTamarix salt glands. The plasmalemma bounds the plasmodesmata and is continuous from cell to cell. In freeze-fracture, the e-face of the plasmalemma within the plasmodesmata is virtually devoid of intramembranous particles while, in contrast, the p-face is decidedly enriched with particles. The axial components appear to be a tightly curved membrane bilayer, as judged from measurements and their appearance in freeze-fracture, and the e-face of this membrane is also devoid of particles. Observations from both thin sections and freeze-fracture replicas indicate the presence of a circular cluster of six particles around the axial component near the cytoplasmic termini of the plasmodesmata. These particles extend from the p-face of the axial component to the p-face of the plasmalemma. These observations are summarized in a model.
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Thomson, W.W., Platt-Aloia, K. The ultrastructure of the plasmodesmata of the salt glands ofTamarix as revealed by transmission and freeze-fracture electron microscopy. Protoplasma 125, 13–23 (1985). https://doi.org/10.1007/BF01297346
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DOI: https://doi.org/10.1007/BF01297346