Thummel says the human equivalent of the fruit fly DHR4 gene probably does not work the same way in people as it does in flies. "But things we can study in detail in the fly, like the role of DHR4 in maturation, will provide new directions for understanding poorly defined processes in humans, such as maturation," he says. "This has been shown over and over again, where people have done studies in the fly and it later has been shown that similar genes work much the same way in humans."
Thummel studied the role of the DHR4 gene with two University of Utah and Howard Hughes Medical Institute colleagues ?postdoctoral researcher Kirst King-Jones and lab technician Geanette Lam ?and with geneticist Jean-Philippe Charles of the University of Bourgogne in Dijon, France.
From Egg to Larva, Pupa and Adult ?Except When the Gene is Disabled
Fruit fly development starts when an egg is laid. Embryonic development proceeds within the egg for 24 hours. Then the egg hatches into a first-stage larva. At 48 hours, the larva molts ?sheds the cuticle that forms its external or exoskeleton ?and becomes a second-stage larva. The larva molts again at 72 hours to become a third-stage larva. At 120 hours ?five days after the egg was laid ?the larva enters metamorphosis and becomes a "prepupa" for 12 hours.
Then "the head pops out of the front end of the animal, and its legs and wings elongate," Thummel says. "Now it is a true pupa, which is an immature adult. It essentially is an adult," except its organs continue to form as it spends another 3.5 days inside its pupal case, which is like a cocoon but made of hard cuticle. Then ?nine days after the egg was laid ?the adult fly crawls out of the pupal case. Fruit flies have a two-month lifespan.
"Teenagers are very pupal ?they go inside their shell and withdraw," Thummel says. "Steroid hormones take over your kid
Source:MWG Biotech AG