Expression Of HEGF In Spirulina Platensis

Human epidermal growth factor(hEGF) is a 53 amino acid peptide,which acts as a growth factor on a wide variety of cell types.Due to its essential biological function and wide spectrum application on clinic,it is the hot spot to study hEGF and its receptors in the research field of biochemistry and molecular biology.Spirulina platensis are a diverse and widely distributed group of prokaryotes with rich protein and nutrition.In recent years there has been rapid progresses on the genetic engineering of spirulina.In this study,the nucleotide sequence of hEGF was obtained by PCR and subcloned into plasmid pUCMTl which contained groESL promoter, Kanamycin resistance gene(nptâ…¡),recA gene and rbcs-polyA terminator,thus the expression vector pKREGF4 was constructed.Then this recombinant donor plasmid was transformed into Spirulina platensis through ultrasonic treatment and the three transformants were obtained by G418 screening,named EGFA,EGFB,EGFC.Results of PCR showed that the target nucleotide had been genetically integrated into genome DNA of host cell by integration vectors.Further confirmation was made by SDS-PAGE and Western Blot. Results indicated that special 8.87kD protein expressed in transformants EGFB and EGFC was coherent with the aimed protein.At last,the curative effect of the transgenic spirulina had been proved by the acetic acid-induced gastric ulcer in rats.In this study,the hEGF had successfully expressed in the Spirulina platensis, which gave the basis for the study on transgenic spirulina.It's the first time to use spirulina as host cell to express EGF.In our future research,we hope that we can develop a new health product which not only act the spirulina function but also perform the health effect of EGF.