Cloning, primary structure determination and expression of preproinsulin cDNA from human insulinoma in Escherichia coli]

A human insulinoma cDNA library was constructed in expression plasmid vector pUEX1. Clone pUEX1Ins12 was selected from human insulinoma cDNA library by means of hybridization with the insulin probe and a nucleotide sequence of the insertion was determined. It codes for full size amino acid sequence preproinsulin and furthermore, contains the entire 3'-end of noncoding mRNA region and 44 nucleotides from the 5'-untranslated region. The bacterial strain pUEX3Ins8 producing preproinsulin as beta-galactosidase fusion protein was constructed.