Vectors that help easy linking of foreign DNA, and selection of recombinants from non-recombinants
(i) 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,controls copy number of the linked DNA
(ii) Selectable marker : In addition to ‘ori’ the vector requires a selectable marker, which helps in identifying and eliminating nontransformants and selectively permitting the growth of the transformants.
(iii) Cloning sites: In order to link the alien DNA, the vector needs to have very few preferably single, recognition sites for the commonly used restriction enzymes.
(iv) Vectors for cloning genes in plants and animals : bacteria and viruses have been used for ages for delivering of genes to transform eukaryotic cells and force them to do what the bacteria or viruses want.(Any Two )
