COPI, or Coat Protein Complex I, is a critical protein complex involved in the intracellular transport of vesicles. It plays a significant role in the endoplasmic reticulum (ER) to Golgi apparatus transport and in retrograde transport from the Golgi back to the ER. COPI-coated vesicles are essential for maintaining the proper functioning and organization of the Golgi complex, ensuring that proteins and lipids are correctly processed and transported within the cell.
