A research team is investigating the role of various cell organelles in protein synthesis, specifically in eukaryotic cells. They have outlined the following organelles: the nucleus, ribosomes, rough endoplasmic reticulum, and Golgi apparatus. The researchers found that a specific mutation in a gene that codes for a transcription factor resulted in reduced mRNA synthesis. Consequently, they observed decreased protein levels in the cell. Based on this information, which organelle would most directly be affected due to the mutation in the gene coding for the transcription factor?