Generation Of Mammary Gland Specific Expressing Transfected Cells And Transgenic Mice For Producing Human Proinsulin

Recently, producing insulin by non islet β cells is research hotspot in biosynthesis of insulin. In β cells, proinsulin was processed by proprotein convertase 1/3 (PC 1/3), proprotein convertase 2 (PC2) and carboxyl peptidase H (CPH), and formed insulin. Previous study showed that PC 1/3 was expression in mammal mammary gland. it will be in favour of producing insulin in mammal mammary gland.In this study, the two sequences of modified human proinsulin gene were biosynthesized, named Seq-662 and Seq-792. An original human proinsulin gene was also biosynthesized as control sequence, named Seq-663. These sequences were inserted into backbone vectors of mammary gland expression, PBC1 and successfully constructed expression vectors of 662-PBC1,663-PBC1,792-PBC1. By transfecting BCAP-37 cells, sixty-five colonies from single cell were isolated, and twenty three of them carried human proinsulin gene. The three transfected cell lines,662-B4,663-4 and 792-F were induced and stimulated by prolectin, hydrocortisone and glucose. The proinsulin expression in these cells was analysized. Results showed that in the same inducing period, expression of insulin was gradually up-regulated with increasing concentration of glucose.In conclusion, we constructed three different plasmids for expressing modified human insulin, and found that it can induce proinsulin gene expression in cells and transgenic mouse in mammary. The study will be basis for producing human proinsulin in domestic animal.