Bacterial expression of cloned gene hMSH2 in E. coli, of mismatch repair system

The pathway of mismatch repair (MMR) can repair mismatches that occur during the several rounds of replication of mitotic DNA preceding meiosis. Mismatch repair would be required to be necessary for the prevention of gene mutations during mitotic expansion and maintenance of the germline. There is evidence that defective repair can lead to cancer and premature ageing in humans. In eukaryotes, MSH2 (MutS homologue is a major player in MMR, has been involved in a variety of processes that serve to protect genomic integrity. The aim of this study was to express the hMSH2 protein in Escherichia coli expression system by using the cloned gene of hMSH2. Full cDNA fragment of hMSH2 gene was cloned into pET32 expression vector to obtain the construct (pET32b-hMSH2). A positive transformant was chosen and plasmids DNA was isolated and successively transformed into competence E. coli BL21(DE3). The bacterium was induced by IPTG and its lysates were loaded directly onto SDS-PAGE. hMSH2 gene was successfully cloned and expressed. An approximately ∼102.8 kDa exogenous protein was analyzed on the SDS-PAGE. Expressing the hMSH2 protein could serve as a basis for further studies on the usefulness of the gene and its expression product identifying the role of hMSH2 gene, understanding the functional diversity of protein that will contribute towards the repair mechanisms.