NEETZoologyBiotechnology - Principles and Processes
A genetic engineer wants to recover a very high number of copies (e.g., 1000 copies per cell) of a target alien DNA. To achieve this, the alien DNA must be cloned into a suitable vector. Which specific sequence of the vector controls this high yield, and which gene codes for the proteins involved in the replication of this plasmid?
Options
- AThe 'rop' gene controls the copy number, and the 'ori' sequence codes for the replication proteins.
- BThe 'ori' sequence controls the copy number, and the 'rop' gene codes for the replication proteins.
- CThe selectable marker controls the copy number, and the 'rop' gene codes for the replication proteins.
- DThe 'ori' sequence controls the copy number, and the amp^ R gene codes for the replication proteins.
Correct answer
B. The 'ori' sequence controls the copy number, and the 'rop' gene codes for the replication proteins.
Step-by-step solution
According to NCERT, the origin of replication ('ori') is a sequence from where replication starts. This sequence is also responsible for controlling the copy number of the linked DNA. Therefore, to recover many copies of the target DNA, it should be cloned in a vector whose origin supports a high copy number. The 'rop' gene codes for the proteins involved in the replication of the plasmid. Thus, the 'ori' sequence controls the copy number, and the 'rop' gene codes for the replication proteins. Answer: The 'ori' seq