Tannisomes: Tannin producing organelles identified in plants
Very cool discovery!
The international team, headquartered at INRA in Montpellier, used a number of techniques to examine the cells in action. In some cases they fixed cells into place, in others they introduced dyes and in more samples they examined spectra, light signatures of chemicals. What they found was that these strange organelles were producing tannins. Until now, no one has known exactly where in the cell tannins have been made. People could see them stored in the vacuole, another organelle in the plant cell, but couldn’t work out how they got there.
Geneviève Conéjéro said: “Tannins, also called condensed tannins or proanthocyanidins, are thought to play diverse roles such as defense against herbivores and pathogens or ultraviolet protection. They give feeling of pungency in the mouth, the feel of a cat’s tongue licking your hand. Common sense associates tannins with immature unripe fruit, and people ironically say ‘this fruit is too green’. More seriously, plant tannins have been used since the Neolithic times to prevent spoilage of animal skins, and therefore first to manufacture leather laces and soles protecting feet of rough ground.”