Monkey Kidney Cells with mRuby-Endosomes
Endosomes were tagged in the African green monkey kidney fibroblast cells (CV-1 line) appearing in this digital video sequence with the red fluorescent protein mRuby. Endosomes are present in almost all animal cells and are formed via a series of processes collectively referred to as endocytosis. The membrane-bound compartments serve as important storage and sorting centers in the endomembrane system. Scientists often consider there to be three different types of endosomes distinguishable by Rab family proteins, the length of time required for matter to arrive at them, and morphology. The primary types are usually referred to as early, late, and recycling endosomes.
mRuby was developed through the mutagenesis of eqFP611, a fluorescent protein that was isolated from Entacmaea quadricolor. Advantages of mRuby include its relative brightness, resistance to acidic environments, and its exhibition of a high Stokes shift. The fluorescent protein, however, is not as photostable as many other red fluorescent proteins.