Ancient duplications of the human proglucagon gene.
The human proglucagon gene (GCG) is encoded within a finished 576-kb DNA sequence generated by the Human Genome Project. GCG is flanked by 18 kb and 65 kb of DNA, 5' and 3', respectively, that do not encode genes. The genomic sequence that includes GCG was found to have a long history of gene duplication events. Some members of the glucagon-like family of genes, GCG on chromosome 2 and GIP on chromosome 17, may be products of ancient genome duplications on the early vertebrate lineage. A large genomic tandem duplication event that included DPP4-like and GCG genes occurred before the amphibian-mammal divergence, but one of the duplicated copies of GCG has been lost on the human lineage. Recently, a processed pseudogene of the X-chromosome-linked gene TIMM8A was inserted downstream of GCG. Some ancient duplicates of GCG may retain physiological functions in other vertebrates.
Irwin
David M
DM
Department of Laboratory Medicine and Pathobiology, Banting and Best Diabetes Centre, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada. david.irwin@utoronto.ca
D000818:Animals; D002135:Calcium-Binding Proteins / Q000235:genetics; D002886:Chromosomes, Human, Pair 17 / Q000235:genetics; D002889:Chromosomes, Human, Pair 2 / Q000235:genetics; D018819:Dipeptidyl Peptidase 4 / Q000235:genetics; D010450:Endopeptidases; D019143:Evolution, Molecular; D018093:Gelatinases; D020440:Gene Duplication; D023061:Gene Order; D005934:Glucagon / Q000235:genetics*; D006801:Humans; D008565:Membrane Proteins / Q000235:genetics; D051379:Mice; D000226:Mitochondrial ADP, ATP Translocases / Q000235:genetics; D010802:Phylogeny; D052336:Proglucagon; D011498:Protein Precursors / Q000235:genetics*; D011544:Pseudogenes / Q000235:genetics; D012697:Serine Endopeptidases / Q000235:genetics; D014714:Vertebrates / Q000235:genetics; D000099167:Fibroblast Activation Protein Alpha
D002135:Calcium-Binding Proteins; D018819:Dipeptidyl Peptidase 4; D010450:Endopeptidases; D018093:Gelatinases; D005934:Glucagon; D008565:Membrane Proteins; D000226:Mitochondrial ADP, ATP Translocases; D052336:Proglucagon; D011498:Protein Precursors; D012697:Serine Endopeptidases; D000099167:Fibroblast Activation Protein Alpha; C503121:GCA protein, human; C503122:Gca protein, mouse