Enteroglucagon and glucagon-like peptides are all derived from the preproglucagon gene. In the a-cells of the pancreas, post-translational cleavage of the preproglucagon mRNA produces glucagon and a large peptide that contains GLP-1 and -2 sequences. In the intestinal L cells, preproglucagon is cleaved into enteroglucagon (which contains the entire sequence of pancreatic glucagon and so is a member of the secretin family) and the two GLPs, GLP-17ΓÇô36NH2 and GLP-2 (see Fig. 19.3).
