Conversion of proglucagon in pancreatic alpha cells: the major endproducts are glucagon and a single peptide, the major proglucagon fragment, that contains two …

C Patzelt, E Schiltz - … of the National Academy of Sciences, 1984 - National Acad Sciences
C Patzelt, E Schiltz
Proceedings of the National Academy of Sciences, 1984National Acad Sciences
It has previously been shown by biosynthetic labeling studies that glucagon is synthesized
in mammalian islets via an 18-kDa precursor, proglucagon, that during processing gives rise
to glucagon and a secreted peptide of 10 kDa (the major proglucagon fragment, MPGF). We
have now developed a simple procedure for the isolation of this peptide from rat pancreatic
islets and have characterized it more fully. On the basis of its amino acid composition, MPGF
is identified as the COOH-terminal portion of proglucagon that contains two glucagon …
It has previously been shown by biosynthetic labeling studies that glucagon is synthesized in mammalian islets via an 18-kDa precursor, proglucagon, that during processing gives rise to glucagon and a secreted peptide of 10 kDa (the major proglucagon fragment, MPGF). We have now developed a simple procedure for the isolation of this peptide from rat pancreatic islets and have characterized it more fully. On the basis of its amino acid composition, MPGF is identified as the COOH-terminal portion of proglucagon that contains two glucagon-related sequences. These sequences do not appear to be liberated from MPGF in alpha cells of the islets of Langerhans but MPGF may be processed further elsewhere in the body or in other cells of the gastrointestinal tract that produce glucagon precursors.
National Acad Sciences