Question

The direction of eukaryotic transcription is

• A. 5’→3’ always
• B. 3’→5’ always
• C. Either 5’→3’ or 3’→5’
• D. Depends upon RNA polymerase

Answer 1

The correct option is A 5’→3’ always

The DNA dependent RNA polymerase is polymerizes the RNA in one direction only i.e 5’→3’. RNA polymerase is a motor protein located in the nucleus in the form of transcription factories. We know that the whole chromosome is not transcribed at once, only a small part is transcribed. The part of a chromosome which is going to transcribe, loops out of its chromosomal territory to the nearby transcription factories and since polymerase is a motor protein, its travels along the template DNA strand in the 3′ to 5′ direction and catalyzes the synthesis of new RNA strands in the 5′ to 3′ direction.