Cloning & Transgenesis
Open Access

Abstract

Designing and Reconstruction of pcDNA 3.0 Mammalian Expression Vector with its Multiple Cloning Sites by Directional Cloning Method

Sheeba Naaz, Syed Naqui Kazim

Traditional cloning is the cloning in which we use restriction endonucleases to produce DNA fragments with specific complementary end sequences that can be joined together with a DNA ligase enzyme, prior to the transformation. The purpose of this study was to reconstruct the mammalian expression vector by replacing the junk DNA with its natural multiple cloning sites. Plasmid was propagated and digested with Xho1 and Kpn1 enzymes from both sides of junk DNA a 600 bp DNA was cut from the vector and then ligation of 30 bp primer which was designed similar as its multiple sequence sites. Correct insertion was confirmed by plasmid isolation, plasmid colony PCR, PCR of cloned plasmid and comparison on gel electrophoresis with the original one and finally by sequencing. An extra DNA fragment of 600 bp was cut from the vector after restriction digestion. Ligated colonies appeared on the agar plate from which 60 bp colony PCR products was produced. Plasmid isolation after cloning and colony PCR and PCR of cloned plasmid confirmed the cloning. Cloning of multiple cloning sites in pcDNA3.0 mammalian expression vector was performed successfully. Ligation of multiple cloning sites in pcDNA vector provided various restriction enzymes recognition sites for simple and fast cloning.