Cloning Vector Introduction
Cloning vectors are DNA molecules used to transfer foreign genetic material into another cell. The vector itself is typically a small, replicable DNA strand.
Replication Capability
Essential for multiplication within host cells, cloning vectors must possess an origin of replication, ensuring both the vector and foreign DNA replicate.
Selectable Markers
Vectors contain selectable markers, often antibiotic resistance genes, allowing researchers to determine if the vector has been taken up by host cells.
Multiple Cloning Site
Vectors feature a multiple cloning site (MCS), a sequence with numerous restriction sites to facilitate the insertion of foreign DNA at this locus.
Size Matters
Vector size affects transformation efficiency. Smaller vectors are more easily taken up by cells, enhancing the success rate of cloning.
High Copy Number
High copy number vectors replicate many times within a cell, increasing the yield of cloned DNA. This is critical for downstream applications.
Unique Cloning Vectors
Beyond basic plasmids, vectors like cosmids, artificial chromosomes, and viral vectors offer specialized functions like cloning very large DNA fragments.