noun, plural: tannosomes
An organelle, particularly a special type of leucoplast, involved primarily in synthesizing tannins and polyphenols
A tannosome is an organelle, particularly a plastid. Plastids are organelles involved in the synthesis and storage of food. They are found within the cells of photosynthetic eukaryotes. In plants, plastids may develop into these forms: (1) chloroplasts, (2) chromoplasts, (3) gerontoplasts, and (4) leucoplasts. Leucoplasts are colourless plastids because they lack pigments. Their role is primarily for storage. Depending on the content of the leucoplasts, they may be amyloplasts, elaioplasts, proteinoplasts, or tannosomes.
Tannosomes are essential in synthesizing and producing tannins and polyphenols. Tannins are bitter-tasting aromatic compounds that are found commonly in bark, leaves, and unripe fruits. It has a protective function to plants as it deters herbivores and pathogens. It is also said to confer protection against UV radiation.
The first to describe this organelle were European researchers. 1 They described the tannosomes as organelles that originate from within the chloroplasts. The chloroplasts are characterized by having thylakoids, which are stacks of membrane-bound discs. The latter forms beads, which later would become tannosomes when they carry tannin, bud off, and are shuttled out of the chloroplast. These tannosomes will be carried off to the vacuole.
1 Grens , K. (2013). New Organelle: The Tannosome. TheScientist.com. Retrieved from ://www.the-scientist.com/?articles.view/articleNo/37597/title/New-Organelle–The-Tannosome/.