Question

Which one of the following statements is CORRECT about Agrobacterium tumefaciens-mediated plant transformation?

• A. The marker gene for the selection of plant transformant is located outside the T-DNA segment of the transformation plasmid
• B. The marker gene for the selection of bacterial transformant is located within the T-DNA segment of the transformation plasmid
• C. Two T-DNA border sequences (left and right) are essential to design a binary vector system
• D. In binary vector system, the vir genes and two T-DNA border sequences (left and right) are present in the same transformation plasmid

Hint:

In Agrobacterium-mediated transformation, the binary vector system separates the vir genes and T-DNA.

Answer 1

The Correct Option is C

Step 1: Analyze the options.
- (A) Incorrect: The marker gene for plant selection is typically within the T-DNA region.
- (B) Incorrect: The marker gene for bacterial transformants is usually located outside the T-DNA region, on the plasmid itself.
- (C) Correct: Two T-DNA border sequences (left and right) are essential for T-DNA insertion into the plant genome in the binary vector system.
- (D) Incorrect: The vir genes and T-DNA border sequences are typically located on separate plasmids in the binary vector system.
Step 2: Conclusion.
The correct statement is that two T-DNA border sequences are essential for binary vector design.
Final Answer: \[ \boxed{\text{Two T-DNA border sequences (left and right) are essential to design a binary vector system.}} \]