This illustration of the inside of a yeast cell shows two mature, or “late” endosomes (green-ringed structures) that are filled with small vesicles (red bubbles). Endosomes are cellular containers that can carry many types of cargo, including cellular waste, which they typically dump into vacuoles (orange). Credit: Matthew West and Greg Odorizzi, University of Colorado, Boulder.
In large offices, mailroom workers read the labels on incoming letters and packages to sort and deliver them and dispose of junk mail. In cells, these tasks—as well as importing food and other materials—fall to small cellular sacs called endosomes. Acting as mailroom staff, endosomes sort and deliver nutrients and building blocks, like amino acids, fat and sugars, to their proper destinations, and send cellular junk, like damaged proteins, to trash processors, such as vacuoles or lysosomes.
Continue reading “The Cell’s Mailroom”