Summary:
Despite its rarity in nature, blue petunias are one of the most sought over flowers by gardeners. Researchers are finally beginning to understand the genetics behind this vividly colored plant. Previously unknown to scientists, in healthy petunias there is a “cellular pump.” This pump brings a large amount of acid to the vacuoles in the plant cells. Vacuoles are special compartments in the cytoplasm (of a cell) where the acid is stored. The “cellular pump” is made out of two proteins working together, and is extremely reliable. Because of its ability to deliver acid for a longer amount of time than other plant pumps, the flower is highly acidic and has a vibrant reddish-violet color. However, mutate petunias contain genes that disables the pump. Because the disabled pump is no longer delivering the huge amount of acid as it typically does, the mutate plants are much less acidic. Therefore, they turn a bluish color, instead of the typical reddish-violet color. These unique flowers are difficult to find in nature due to their coloring. The blue petals do not attract as many insects (for pollination) as its sister plant, thus placing them at an evolutionary disadvantage. Since it is the “survival of the fittest” in nature, the wild blue petunias have nearly died out. Nowadays, most of these vividly colored plants can only be found at the plant breeders. The discovery of this pump opens a huge window of opportunities for researchers. By changing the amount of acid in a plant, scientists can manipulate the taste and color of other plants.
Relevance:
This relates to our seventh unit about the evolution of life, and touches upon the subject of molecular genetics. To have such a vivid blue color on the petals of the petunias, the plants must have mutate genes. In unit six, we learned that a mutation is a change in genetic information. Therefore, a blue petunia must have slightly different genes compared to its reddish- violet sister plant. This difference is what causes the cellular pump to be deactivated, and thus causing a different acidity of the plant (which causes the unique blue coloring). In our seventh unit, natural selection was a major topic. It is the idea that only the fittest survive and reproduce. Because of the coloring of the blue petunia, the plant is unable to attract many insect. Insects are vital for the reproduction of the plant because they pollinate the petunia. Because of this “evolutionary disadvantage,” blue petunia are extremely hard to find in nature because they have all died out. It is only because of human intervention and our artificial breeding that they are still a preserved species.
Citation:
Author:
Douglas Quenqua
Date of Publication:
January 6, 2014
Article Link:
Picture of a blue petunia:
Where does the acid that is "pumped" into the vacuole come from?
ReplyDeleteMost plants extract the acid from the soil. You can tell that this is the case for the petunia because the acid is pumped up. That is why the leaves of the (normal) petunia are such a cool shade of red (in the reading above).
ReplyDeleteread more at http://news.sciencemag.org/biology/2014/01/scienceshot-broken-pump-turns-petunias-blue