Insuling, aging, and mass

Scientists from the new interdisciplinary LIMES (Life & Medical Sciences) Centre at the University of Bonn have identified a new gene which could play an important role in the development of diabetes. Flies in which this hereditary factor is defective are also significantly smaller than other members of their species and live appreciably longer. The gene seems to have such a crucial function that it has hardly changed in just under a billion years: it is found in flies, but in a similar form it is also found in mice and humans. In the current issue of the prestigious journal Nature the Bonn researchers have published two articles on this topic.

Sometimes science resembles a relay race: in 1996 the biochemist Professor Waldemar Kolanus discovered a group of cellular proteins, the cytohesins, and described their function in the immune system. Two of his colleagues at the LIMES Centre in Bonn have now found a totally new and completely unexpected function of these proteins which is very relevant to medicine. 'We wanted to know whether there were also cytohesins in the fruit fly drosophila and what functions they have there,' the evolutionary biologist Professor Michael Hoch reminisces. He and his team were in fact successful. They discovered a protein which is very similar to the cytohesins in mammals. Even more interestingly, fruit flies in which the genetic blueprint for this gene is defective are smaller in size. So the researchers nicknamed cytohesin 'Titch'. 'The effect on the insect's growth showed us that 'Titch' could play a key role in the metabolism of insulin – a completely new role for cytohesins,' Professor Hoch says.