Question

Arrange the different steps of transcription in the correct order:
(A) Transcription bubble formation
(B) Phosphorylation of CTD tail
(C) Recruitment of elongation factors
(D) Dephosphorylation of CTD tail
Choose the correct answer from the options given below:

• A. (A), (B), (C), (D)
• B. (A), (C), (B), (D)
• C. (B), (A), (D), (C)
• D. (C), (B), (D), (A)

Hint:

Understand the stages of transcription, including initiation, elongation, and termination, and the role of the CTD tail in RNA polymerase function.

Answer 1

The Correct Option is A

Transcription converts genetic information from DNA into RNA. The process involves these steps:
1. Transcription bubble formation (A): DNA unwinds, creating a transcription bubble that exposes the template strand for RNA synthesis.
2. CTD tail phosphorylation (B): The C-terminal domain (CTD) of RNA polymerase II is phosphorylated. This modification is crucial for transitioning the polymerase from initiation to elongation.
3. Elongation factor recruitment (C): During elongation, various factors are recruited to stabilize the transcription complex and assist RNA polymerase in synthesizing the RNA strand.
4. CTD tail dephosphorylation (D): At transcription's end, the CTD tail is dephosphorylated, facilitating termination and release of the RNA transcript.