# DBT JRF 2022 — Question 29

Exam: DBT JRF 2022 · Section: A · Topic: Molecular Biology › Transcription Factors & PIC Assembly · Difficulty: Medium

## Question

For transcribing protein coding genes, the RNA Polymerase forms the preinitiation complex (PIC) in association with:

## Options

- **A.** TFIIA, TFIID, TFIIG
- **B.** TFIIA, TFIIG, TFIIH
- **C.** TFIIH, TFIIF, TFIID
- **D.** TFIIC, TFIID, TFIIF

## Answer

Option C

## Explanation

RNA Pol II Preinitiation Complex (PIC) formation: For RNA Pol II to begin transcription, it must assemble the PIC in a defined order: 1. TFIID (containing TBP): Binds the TATA box, nucleating PIC assembly. 2. TFIIA: Stabilises TFIID-TATA interaction. 3. TFIIB: Bridges TFIID and Pol II; required for Pol II recruitment. 4. TFIIF: Brings RNA Pol II to the promoter; stabilises the Pol II–TFIIB interaction. 5. TFIIE and TFIIH: Join later; TFIIH has helicase activity to unwind DNA at the TSS and CDK7 kinase activity to phosphorylate the CTD of Pol II, triggering promoter clearance and elongation. The minimal functional complex includes TFIID, TFIIF, and TFIIH (Option 3). TFIIG and TFIIC do not exist in Pol II transcription. Answer: TFIIH, TFIIF, TFIID (Option 3).

Source: https://mypyqbuddy.com/questions/for-transcribing-protein-coding-genes-the-rna-polymerase-6a104cd5920734408bc0c6fa