Insulin Through the Ages: Phylogeny of a Growth Promoting and Metabolic Regulatory Hormone
Open Access
- 1 April 2000
- journal article
- research article
- Published by Oxford University Press (OUP) in American Zoologist
- Vol. 40 (2), 213-222
- https://doi.org/10.1093/icb/40.2.213
Abstract
Insulin was discovered in 1922 as the causative factor for a human metabolic disorder (diabetes mellitus), but it was recognized early that the hormone had a broad phylogenetic distribution. By the mid 1970s, insulin had been isolated and sequenced from all classes of vertebrates, including Agnatha. Also it was discovered that the insulin gene family in vertebrates included two closely related hormones named insulin-like growth factor (IGF)-I and -II. More recently, the application of recombinant DNA techniques have identified insulin-like peptide genes in invertebrates, including insects, molluscs and nematode and these findings clearly establish that insulin is an evolutionarily ancient hormone which is present in all metazoa. Here we briefly review the structure and function of the insulin/IGF gene family in vertebrates and invertebrates. Although these studies are ongoing, it appears that in invertebrates the insulin-like peptides function predominately as mitogenic growth factors that act to promote tissue growth and development. However, in vertebrates the mitogenic growth function has been subsumed by IGF-I and -II while insulin has acquired the function of being primarily a metabolic regulatory hormone. The gene duplication and divergence events necessary for this development probably occurred early during vertebrate evolution in the transition from protochordates, represented by extant amphioxus, to primitive jawless vertebrates, represented by extant lamprey and hagfish.Keywords
This publication has 32 references indexed in Scilit:
- Cloning and Developmental Regulation of a Novel Member of the Insulin-like Gene Family inCaenorhabditis elegansBiochemical and Biophysical Research Communications, 1998
- daf-2 , an Insulin Receptor-Like Gene That Regulates Longevity and Diapause in Caenorhabditis elegansScience, 1997
- Multiple Gene Copies for Bombyxin, an Insulin-related Peptide of the Silkmoth : Structural Signs for Gene Rearrangement and Duplication Responsible for Generation of Multiple Molecular Forms of BombyxinJournal of Molecular Biology, 1996
- Divergence of insulin‐like growth factors I and II in the elasmobranch, Squalus acanthiasFEBS Letters, 1995
- Role of insulin-like growth factors in embryonic and postnatal growthCell, 1993
- cDNAs from neurosecretory cells of brains of Locusta migratoria (Insecta, Orthoptera) encoding a novel member of the superfamily of insulinsEuropean Journal of Biochemistry, 1990
- Mechanical energy budget of a fold-and-thrust beltNature, 1988
- STRUCTURE AND EVOLUTION OF THE INSULIN GENEAnnual Review of Genetics, 1985
- Structure and biological activity of hagfish insulinJournal of Molecular Biology, 1979
- Primary structure of human insulin‐like growth factor IIFEBS Letters, 1978