Grey Fox Lung Cells with mRuby-EB3
The lungs are the elastic respiratory organs of vertebrates that breathe air. In humans, the lungs are paired in the chest cavity on opposite sides of the heart. The right lung is divided into three lobes and the left is composed of two lobes. A membranous lining called the pleura covers the lungs, as well as the upper body cavity. A small amount of watery fluid is generally present in the pleural cavity that keeps the pleura lubricated and allows the lungs to move smoothly in the chest cavity during the breathing process.
The dynamic nature of the intracellular microtubule network is highlighted in this digital video sequence featuring FoLu cells tagged with mRuby fused to EB3. EB3 is a member of a specialized family of microtubule end-binding proteins, specifically localized to the positive end of the microtubule, which is the end where growth occurs the fastest. By fluorescently tagging EB3, the continual polymerization and depolymerization of tubulin becomes readily observable.
The fluorescent protein employed to visualize microtubule growth, mRuby, was developed via the mutation of eqFP611. Initially isolated from the sea anemone Entacmaea quadricolor, eqFP611 is a far-red fluorescent protein that exhibits a high Stokes shift. The monomeric variant mRuby retains the high Stokes shift, but with the advantage of improved brightness.