Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Linchpin discovered in insulin metabolism

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.

New drugs for diabetes

... more about:
»Famulok »Insulin »SecinH3 »metabolism

The maximum size of plants or animals is written into their genes. Yet whether they exploit this potential is influenced by a number of other factors. One of them is insulin. Mammals produce increased amounts of this hormone after eating as a reaction to the increasing blood sugar level. Via a complicated sequence of reactions it ensures that muscles and other organs absorb blood sugar. What is more, however, the cascade of insulin signals also determines size and number of the body cells during growth. Apparently, ‘Titch’ plays a key role in this shower of signals. ‘The fruit fly larvae increase their weight 200-fold in the first three days after hatching,’ Michael Hoch explains. ‘If their 'Titch gene' has mutated, they grow visibly more slowly.’ A series of additional observations support the thesis that ‘Titch’ is extremely important for the metabolism of insulin in drosophila. If there were a cytohesin with a similar function in mammals, this would, for instance, be of great interest for research into diabetes.

In parallel to Michael Hoch's research, Professor Michael Famulok produced an active substance that inhibits cytohesins, known as SecinH3. ‘We fed this inhibitor to mice,’ he explains. Unlike fruit flies, the rodents do not have just one cytohesin at their disposal, they have four. Professor Famulok wanted to find out whether they play a similar crucial role in the insulin metabolism of mice as ‘Titch’ does in the fly and discovered the following: ‘Liver cells of the animals treated with SecinH3 reacted to insulin not nearly as strongly as they should.’ Medical people know this effect: this insulin resistance is regarded as a warning signal for the onset of Type II diabetes.

Six million people suffer from this type of diabetes in Germany alone. It is triggered by an unhealthy diet and lack of exercise, and the tendency is rising. Michael Famulok now thinks new drugs are on the cards. ‘There is a class of switch molecules which are activated by cytohesins. This activation is apparently necessary to pass on the signals. If we manage to stimulate the switch molecules with a suitable active substance, we might possibly be able to thereby reverse the resistance to insulin.’ A new method described by Michael Famulok in the Nature paper could help in the search for this kind of drug. With its help his team has already found the inhibitor SecinH3.

A long life thanks to a genetic defect?

The joint ancestor of the fruit fly and the mouse lived at least 900 million years ago. Nevertheless, ‘Titch’ and the corresponding cytohesin in mice are so similar that SecinH3 is effective with both. ‘We have fed the inhibitor to our fly larvae,’ Michael Hoch explains. ‘They then developed as if their 'Titch gene' were defective.’ This hereditary factor also has a completely different effect, which really sets the researchers’ imagination going. Flies which have a ‘Titch’ defect live a lot longer than others of their species. ‘An exciting effect,’ Michael Hoch thinks. ‘We certainly must investigate this further.’

Prof. Dr. Michael Famulok | alfa
Further information:

Further reports about: Famulok Insulin SecinH3 metabolism

More articles from Life Sciences:

nachricht Don't Give the Slightest Chance to Toxic Elements in Medicinal Products
23.03.2018 | Physikalisch-Technische Bundesanstalt (PTB)

nachricht North and South Cooperation to Combat Tuberculosis
22.03.2018 | Universität Zürich

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Space observation with radar to secure Germany's space infrastructure

Satellites in near-Earth orbit are at risk due to the steady increase in space debris. But their mission in the areas of telecommunications, navigation or weather forecasts is essential for society. Fraunhofer FHR therefore develops radar-based systems which allow the detection, tracking and cataloging of even the smallest particles of debris. Satellite operators who have access to our data are in a better position to plan evasive maneuvers and prevent destructive collisions. From April, 25-29 2018, Fraunhofer FHR and its partners will exhibit the complementary radar systems TIRA and GESTRA as well as the latest radar techniques for space observation across three stands at the ILA Berlin.

The "traffic situation" in space is very tense: the Earth is currently being orbited not only by countless satellites but also by a large volume of space...

Im Focus: Researchers Discover New Anti-Cancer Protein

An international team of researchers has discovered a new anti-cancer protein. The protein, called LHPP, prevents the uncontrolled proliferation of cancer cells in the liver. The researchers led by Prof. Michael N. Hall from the Biozentrum, University of Basel, report in “Nature” that LHPP can also serve as a biomarker for the diagnosis and prognosis of liver cancer.

The incidence of liver cancer, also known as hepatocellular carcinoma, is steadily increasing. In the last twenty years, the number of cases has almost doubled...

Im Focus: Researchers at Fraunhofer monitor re-entry of Chinese space station Tiangong-1

In just a few weeks from now, the Chinese space station Tiangong-1 will re-enter the Earth's atmosphere where it will to a large extent burn up. It is possible that some debris will reach the Earth's surface. Tiangong-1 is orbiting the Earth uncontrolled at a speed of approx. 29,000 km/h.Currently the prognosis relating to the time of impact currently lies within a window of several days. The scientists at Fraunhofer FHR have already been monitoring Tiangong-1 for a number of weeks with their TIRA system, one of the most powerful space observation radars in the world, with a view to supporting the German Space Situational Awareness Center and the ESA with their re-entry forecasts.

Following the loss of radio contact with Tiangong-1 in 2016 and due to the low orbital height, it is now inevitable that the Chinese space station will...

Im Focus: Alliance „OLED Licht Forum“ – Key partner for OLED lighting solutions

Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP, provider of research and development services for OLED lighting solutions, announces the founding of the “OLED Licht Forum” and presents latest OLED design and lighting solutions during light+building, from March 18th – 23rd, 2018 in Frankfurt a.M./Germany, at booth no. F91 in Hall 4.0.

They are united in their passion for OLED (organic light emitting diodes) lighting with all of its unique facets and application possibilities. Thus experts in...

Im Focus: Mars' oceans formed early, possibly aided by massive volcanic eruptions

Oceans formed before Tharsis and evolved together, shaping climate history of Mars

A new scenario seeking to explain how Mars' putative oceans came and went over the last 4 billion years implies that the oceans formed several hundred million...

All Focus news of the innovation-report >>>



Industry & Economy
Event News

New solar solutions for sustainable buildings and cities

23.03.2018 | Event News

Virtual reality conference comes to Reutlingen

19.03.2018 | Event News

Ultrafast Wireless and Chip Design at the DATE Conference in Dresden

16.03.2018 | Event News

Latest News

For graphite pellets, just add elbow grease

23.03.2018 | Materials Sciences

Unique communication strategy discovered in stem cell pathway controlling plant growth

23.03.2018 | Agricultural and Forestry Science

Sharpening the X-ray view of the nanocosm

23.03.2018 | Physics and Astronomy

Science & Research
Overview of more VideoLinks >>>