title: Synthesis of a human insulin gene. VII. Synthesis of preproinsulin-like human DNA, its cloning and expression in M13 bacteriophage.
abstract: A 74-bp DNA sequence coding for the pre sequence of human preproinsulin and containing EcoRI termini was synthesized by the chemical enzymatic method, joined with previously synthesized proinsulin DNA, and cloned in the M 13mp8 vector. A clone pNB82 -121 was identified by DNA sequence which confirmed the correct orientation of the pre sequence to the proinsulin DNA. The EcoRI site at the junction of pre- and proinsulin DNA was eliminated by removing a triplet ATT using a synthetic 19-mer primer. To simplify preproinsulin isolation and to study its expression in the M 13 system, a 25-bp affinity leader sequence coding for (glu)7 was inserted at the remaining EcoRI site; this put the preproinsulin DNA in a correct reading frame with the AUG initiation codon of beta-galactosidase. Preproinsulin was expressed under lac promoter control as analyzed by a radioimmunoassay (RIA) against C-peptide.
mesh_terms: D001483:Base Sequence; D002096:C-Peptide / Q000032:analysis; D003001:Cloning, Molecular; D003090:Coliphages / Q000235:genetics; D004247:DNA / Q000138:chemical synthesis*; D004926:Escherichia coli / Q000235:genetics; D005786:Gene Expression Regulation; D005813:Genes, Synthetic; D007328:Insulin; D009154:Mutation; D011384:Proinsulin / Q000235:genetics*; D011498:Protein Precursors / Q000235:genetics*; D011863:Radioimmunoassay
chemical_list: D002096:C-Peptide; D007328:Insulin; D011498:Protein Precursors; C013737:preproinsulin; D004247:DNA; D011384:Proinsulin