In eukaryotic cells, transcription cannot begin until which of the following occurs?

• A. DNA polymerase binds to the origin of replication
• B. The mRNA is exported from the nucleus
• C. The ribosome attaches to the mRNA
• D. Transcription factors bind to the promoter region of the gene

Answer: (D)

Verified step by step guidance

1. Understand that transcription is the process of synthesizing RNA from a DNA template, and it occurs in the nucleus of eukaryotic cells.
2. Recognize that transcription in eukaryotic cells requires the enzyme RNA polymerase, but RNA polymerase cannot bind directly to the DNA on its own.
3. Learn that transcription factors are proteins that help RNA polymerase locate and bind to the promoter region of a gene, which is a specific sequence of DNA upstream of the gene to be transcribed.
4. Note that the promoter region contains specific sequences, such as the TATA box, which transcription factors recognize and bind to, forming a transcription initiation complex.
5. Conclude that transcription cannot begin until transcription factors bind to the promoter region, enabling RNA polymerase to attach and initiate RNA synthesis.