A drug interferes with vesicle budding from the rough ER. Cells treated with the drug accumulate newly synthesized secretory proteins inside the ER and fail to release them. Both Golgi and plasma membrane look normal.
Which step of the endomembrane pathway is MOST directly disrupted?
- A
Lipid synthesis at the smooth ER
- B
Translation of mRNA on cytosolic ribosomes
- C
DNA replication in the nucleus
- Dcheck_circle
Vesicle budding from the ER carrying cargo to the Golgi
Explanation
Without ER-to-Golgi vesicle budding, secretory proteins synthesized in the ER cannot exit and accumulate, even though later steps remain functional.