DNA construct

[4] Typically, the vectors used in DNA constructs contain an origin of replication, a multiple cloning site, and a selectable marker.

[2] Certain vectors can carry additional regulatory elements based on the expression system involved.

[5] DNA constructs can be as small as a few thousand base pairs (kbp) of DNA carrying a single gene, using vectors such as plasmids or bacteriophages, or as large as hundreds of kbp for large-scale genomic studies using an artificial chromosome.

The plasmid contains various restriction enzyme sites and a stable antibiotic-resistance gene free from transposon activities.

[3] To synthesize a larger gene, oligonucleotides are developed with overlapping sequences on the ends and then joined together.

[2] An alternative strategy uses recombination between homologous sites on the target gene and the vector sequence, eliminating the need for restriction enzymes.

[8] There are three general categories of DNA construct delivery: physical, chemical, and viral.

[10][11] Viral methods use a variety of viral vectors to deliver the DNA, including adenovirus, lentivirus, and herpes simplex virus[12] In addition to the target gene, there are three important elements in a vector: an origin of replication, a selectable marker, and a multiple cloning site.