Proteins are translated into the ER and then carried to the Golgi apparatus where they are packaged into vesicles and transported throughout the cell. Clicking
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After entering the cytoplasm, mRNA binds to a ribosomal sub-unit and serves as a template for translation--the process by which ribosomes, mRNA, and tRNA join together and build proteins out of specific amino acids.
Ribosomes can be found floating in the cytoplasm of the cell, or attached to the endoplasmic reticulum or nuclear membrane. Ribsomes attached to the ER insert the proteins they translate directly into the space inside the ER membrane.
Proteins from inside the ER can be packaged into cargo vesicles and transported along microtubules to the Golgi apparatus for further modification and distribution within the cell.
Inside the Golgi, some proteins are modified with specific molecular tags. These tags help to target the protein to its final destination.
As the Golgi cisternae mature, they eventually join the Trans Golgi Network and break off into transport vesicles. These vesicles contain proteins destined for specific locations within the cell.
Hydrolase enzymes are tagged for delivery to organelles such as the endosome.
Other proteins like interleukins, are destined for delivery to the cell's plasma membrane where they will be secreted from the cell.