Describe the important features that are required to facilitate cloning into a vector.
Answers
Origin of Replication (Ori):
This is a sequence from where replication starts and any piece of DNA, when linked to this sequence can be made to replicate within the host cells.
This sequence is also responsible for controlling the copy number of the linked DNA.
Selectable Marker:
It helps in identifying or selecting transformants and eliminating non-transformants; and selectively permits the growth of the transformants.
Cloning (Recognition) Sites:
These are generally required to link the foreign or alien DNA with the vector. For this, the vector requires very few or single recognition sites for commonly used restriction enzymes. If more than one recognition sites is present within the vector, it will generate several fragments that will lead to more complication in gene cloning.