To keep a city running, traffic must keep flowing. The same goes for cells. Cargo is packaged up in vesicles in a structure called the Golgi and transported throughout the cell. Some vesicles are coated in a protein called COP1, which controls vesicle traffic through the Golgi. The structure of the mammalian version of COP1 was uncovered from experiments conducted outside the cell. Researchers have now investigated the structure of COP1 in its native habitat by studying COP1 in Chlamydomonas reinhardtii algae using cryo-electron tomography. They found it looks similar to COP1 in mammals. They also noticed that as the vesicles (pictured, light pink/light blue/light green) moved through different parts of the Golgi (green/magenta/blue/purple), they changed size, membrane thickness and cargo, but the structure of their COP1 coating remained the same. This approach provides a clearer picture of what COP1 and COP1-coated vesicles get up to in the cell.
Written by Lux Fatimathas
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