An Academic Valentine: The Science Behind Flower Color
Morning Glory Buds are Red
And they Open to Bright Blue
But in NHX1 Mutants
They can’t Change their Hue
✿ We all know that roses are red and violets are blue, but did you also know that vacuolar pH determines their hue? Flowers are colored by anthocyanin pigments that collect in the vacuoles of petal cells. Their color is determined by the acidity, or pH of the vacuole. Vacuolar pH is set by a balance of proton (H+) pumps and leaks. A family of leak proteins known as sodium hydrogen exchangers is found in all cells from yeasts, plants and animals. They work to keep vacuoles and other cell compartments from becoming too acidic.A dramatic example is that of the Japanese morning glory (Ipomoea nil) where mutants in the leak protein, NHX1, fail to achieve that brilliant blue when they flower. The first NHX1 gene was cloned by our lab from yeast in the mid-nineties. More recently, mutations in the human genes have been linked to autism, Alzheimer’s disease, seizures and cognitive disabilities, in ways that we are only just beginning to understand.
#valentinesday #AcademicValentine #ScienceEveryday
✿ Image: From the review by Jon Pittman http://www.frontiersin.org/Journal/10.3389/fpls.2012.00011/full