Protein Trafficking (Golgi):
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Proteins must be transported through the Golgi, as well as away from the Golgi to their final locations. Clicking
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According to the cis maturation model, the proteins are transported through the Golgi stack as the cisterna containing them migrate, or mature, in a cis-to-trans direction. New vesicles from the ER continually supply new cis cisterna as trans Golgi network vesicles mature.
Within the trans Golgi network, proteins are sorted by their final destinations. This is accomplished by receptor molecules embeddedin the membrane of the TGN.
When proteins have reached their correct location within the TGN, the membrane at those locations buds off into vesicles. More than one protein can be contained within each transport vesicle.
Once released, the vesicles carry their cargo proteins to a final location. Possible destinations include the lysosome, the digestive organelle of the cell, and the plasma membrane, where the proteins can be released elsewhere in the organism.