Insulin/insulin-like growth factor (IGF)-1 signaling (IIS) pathway regulates aging in many organisms ranging from simple invertebrates to mammals including humans. Many seminal discoveries regarding the roles of IIS in aging and longevity have been made by using the roundworm Caenorhabditis elegans and the fruit fly Drosophila melanogaster. In this review, we describe mechanisms by which various IIS components regulate aging in C. elegans and D. melanogaster. We also cover systemic and tissue-specific effects of the IIS components on the regulation of lifespan. We further discuss IIS-mediated physiological processes other than aging and its effects on human disease models focusing on findings that used C. elegans. As both C. elegans and D. melanogaster have been essential for key findings regarding the effects of IIS on organismal aging in general, these invertebrate models will continue to serve as workhorses to help our understanding of mammalian aging.
In the end, it is attention to detail that makes all the difference. It's the center fielder's extra two steps to the left, the salesman's memory for names, the lover's phone call, the soldier's clean weapon. It is the thing that separates the men from the boys, and, very often, the living from the dead. Professional success depends on it, regardless of the field. But in big-time genetic research, attention to detail is more than just a good work habit, more than a necessary part of the routine. In big-time genetic research, attention to detail is the very meat and the god of science. It isn't something that's expected; it is simply the way of things. Those in the field, particularly those who lead the field, are slaves to detail. They labor in submerged mines of it, and haul great loads of it up from the bottom of an unseen ocean-the invisible sea of biological phenomena, upon which all living things float. Detail's rule over genetics is total and cruel. Months and even years of work have literally gone down the drain because of the most minor miscalculations. Indeed, perhaps the greatest discovery in the history of the discipline-the double-helix structure of DNA-might have been made by Linus Pauling instead of James D. Watson and Francis H. C. Crick. But Pauling's equations contained a simple mistake in undergraduate-level chemistry, a sin against detail that is now part of the legend. Each of the six scientists singled out here has made his mark by mastering his own particular set of