Question

The expression of a gene is regulated by a transcription factor. Which of the following techniques can be used to identify the region in its promoter where the transcription factor binds?

• A. {S1 nuclease mapping}
• B. {Chromatin immunoprecipitation followed by sequencing}
• C. {Electrophoretic mobility shift assay}
• D. {DNase I footprinting}

Hint:

To identify transcription factor binding sites, techniques like ChIP-Seq and DNase I footprinting are invaluable as they provide precise mapping of protein-DNA interactions.

Answer 1

The Correct Option is B, D

To identify the region where a transcription factor binds in a gene's promoter, the following techniques are commonly used: 
- Chromatin immunoprecipitation followed by sequencing (ChIP-Seq) (option B) is a powerful technique used to identify binding sites of transcription factors on DNA. It involves crosslinking DNA-protein complexes, immunoprecipitating the protein of interest, and sequencing the associated DNA. This method can provide high-resolution information on transcription factor binding regions.
- DNase I footprinting (option D) is another technique that identifies the exact DNA sequence where proteins, like transcription factors, bind. The region bound by the protein is protected from DNase I digestion, creating a "footprint" in the sequence. This allows researchers to pinpoint the binding sites.
Thus, the correct answer is (B) and (D).