Question

Which of the following techniques can be used to detect protein-protein interactions in-vivo?
(P) Two hybrid assay
(Q) Fluorescence resonance energy transfer
(R) Fluorescence recovery after photobleaching
(S) Gel-shift assay

• A. P and Q
• B. P and S
• C. Q and R
• D. P, Q and S

Hint:

For in-vivo detection of protein-protein interactions, techniques like the two-hybrid assay and fluorescence resonance energy transfer (FRET) are commonly used. The gel-shift assay can be adapted for protein interactions, but it is primarily used for DNA-protein interactions.

Answer 1

The Correct Option is A

Step 1: Understanding the techniques.
- Two hybrid assay (P): This technique is commonly used to detect protein-protein interactions in-vivo. It helps identify interactions by bringing together two interacting proteins and detecting the interaction based on the expression of a reporter gene.
- Fluorescence resonance energy transfer (Q): This method detects protein-protein interactions in living cells by measuring the transfer of energy between two fluorescently labeled molecules when they are in close proximity.
- Fluorescence recovery after photobleaching (R): This technique is used to study protein dynamics in vivo but is less commonly used specifically for protein-protein interactions compared to others.
- Gel-shift assay (S): This technique is used to study DNA-protein interactions but can also be adapted for protein-protein interactions, particularly in vitro.

Step 2: Analyzing the options.
- (A) P and Q: These two techniques are indeed commonly used for detecting protein-protein interactions.
- (B) P and S: While the two-hybrid assay is used for protein-protein interactions, the gel-shift assay is more typically used for DNA-protein interactions.
- (C) Q and R: Fluorescence resonance energy transfer is suitable for protein-protein interaction detection, but fluorescence recovery after photobleaching is not typically used for this purpose.
- (D) P, Q and S: All three of these techniques can be used to detect protein-protein interactions, making this the correct answer.

Final Answer: \[ \boxed{\text{(D) P, Q and S.}} \]