Question

Which of the following promotes branch migration at higher rates than does Rec-A?

• A. Rec-B
• B. Rec-C
• C. Rec-D
• D. Ruv-A and Ruv-B

Hint:

Ruv-A and Ruv-B proteins are key to promoting efficient branch migration during recombination, allowing the recombination process to proceed at higher rates.

Answer 1

The Correct Option is D

Step 1: Understanding the proteins involved in branch migration.
Rec-A is a protein involved in homologous recombination, promoting the strand invasion process. However, Ruv-A and Ruv-B proteins are involved in branch migration during recombination, enhancing the rate of migration compared to Rec-A.
Step 2: Analyzing the options.
(1) Rec-B: This is incorrect as Rec-B is part of the RecBCD complex that initiates recombination but is not as effective in branch migration as Ruv-A and Ruv-B.
(2) Rec-C: Rec-C is also involved in DNA recombination but does not enhance branch migration more than Rec-A.
(3) Rec-D: Rec-D is another subunit of RecBCD, but it does not promote branch migration more than Rec-A.
(4) Ruv-A and Ruv-B: Correct — Ruv-A and Ruv-B are directly involved in branch migration during homologous recombination and promote migration at higher rates than Rec-A.
Step 3: Conclusion.
The correct answer is (4) Ruv-A and Ruv-B, as they promote branch migration more effectively than Rec-A.