Practice question

Question

Researcher plans to study protein trafficking into the endoplasmic reticulum (ER). For this purpose, they plan different experimental conditions shown below: A. The cytosol is mixed with mRNA that codes for a secreted protein, followed by wesiern blotting with antibodies against secreted protein. B. The cytosol is mixed with mRNA that codes for a secreted protein and rough microsomes, followed by western blotting with antibodies against secreted protein. C. The cytosol is mixed with mRNA that codes for a secreted protein and rough microsomes followed by protease treatment. Subsequently, western blotting with antibodies against secreted protein is done Consider that mRNA that codes for a secreted protein is added in abundant amount, which experimental control/s would be the best to confirm the polypeptide entry into the ER?