Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

UM Scientists Create Fruit Fly Model to Help Unravel Genetics of Human Diabetes

04.11.2009
As rates of obesity, diabetes, and related disorders have reached epidemic proportions in the US in recent years, scientists are working from many angles to pinpoint the causes and contributing factors involved in this public health crisis.

While sedentary lifestyles and diets high in sugar and fat contribute significantly to the rise in diabetes rates, genetic factors may make some people more vulnerable than others to developing diabetes.

Researchers at the University of Maryland are using the fruit fly, Drosophila Melanogaster, as a model system to unravel what genes and gene pathways are involved in the metabolic changes that lead to insulin resistance and full-blown diabetes in humans. In research published in the Proceedings of the National Academy of Sciences (November 2, 2009), Leslie Pick, an associate professor in the department of entomology, and colleagues describe how they altered genes in fruit flies to model the loss of insulin production, as seen in human Type 1 diabetes.

"These mutant flies show symptoms that look very similar to human diabetes," explains Dr. Pick. "They have the hallmark characteristic which is elevated blood sugar levels. They are also lethargic and appear to be breaking down their fat tissue to get energy, even while they are eating -- a situation in which normal animals would be storing fat, not breaking it down."

Understanding Type 1 Diabetes
In mammals, insulin is a key hormone required for sugar metabolism. After a meal, blood sugar levels rise. Insulin triggers the uptake of this sugar from circulation to be converted into storage products in tissues such as muscle and fat. In humans, Type 1 diabetes (also called Juvenille Diabetes Mellitus, or early onset diabetes), insulin production fails. As a result, the body is missing the key signal required for uptake of sugar from the circulation. Circulating sugar levels continue to rise, as the body fails to sense the presence of sugar, and instead responds as if it is starving, beginning to break down storage products to produce energy.

Pick and her team, which included University of Maryland researchers Hua Zhang, Jingnan Liu, and Caroline Li, Associate Professor Bahram Momen (biostatistics and environmental science), and former Johns Hopkins University Associate Professor Dr. Ronald Kohanski, used genetic approaches to delete a cluster of five genes encoding insulin-like peptides (Drosophila insulin-like peptides, DILPs) in the Drosophila melanogaster fruit fly. "When we compare the mutants with a normal fly that has been starved, they look the same in that they are both breaking down their fat to get energy," Pick explains. This mimics a clinical feature of diabetic patients resulting from the fact that nutrients are present but the body cannot utilize them and thus mounts a starvation response, breaking down energy stores to obtain nutrients.

"We can use these genetically manipulated flies as a model to understand defects underlying human diabetes and to identify genes and target points for pharmacological intervention," suggests Dr. Pick, who is also using flies to study Type 2 diabetes and other syndromes of insulin resistance.

Model organisms have proven enormously valuable for studies of human disease mechanisms because regulatory pathways and physiology are so highly conserved throughout the animal kingdom. The relationship between fly and human genes is so close that human genes, including disease genes, can often be matched against their fly counterparts.

"Way more is shared between flies and humans than we ever would have expected before we started identifying the genes," says Pick. Using flies as a model system has advantages over studies in other animals, such as mice, because the experiments can be done quickly in thousands of flies and because scientists can combine different mutations much more easily. This could prove valuable in understanding the genesis of Type 2 diabetes in which scientists believe multiple genes play a role.

"When we made the genetic mutation that deleted these genes, we asked would these flies have any symptoms of human diabetes, and it turns out they do," Pick says. "That tells us that there are some things going on that are very similar. Our hope is that this provides a valuable resource for the scientific community to identify gene targets for diabetes treatment."

This research was funded primarily by the National Institutes of Health.

Kelly Blake | EurekAlert!
Further information:
http://www.umd.edu

More articles from Life Sciences:

nachricht Rainbow colors reveal cell history: Uncovering β-cell heterogeneity
22.09.2017 | DFG-Forschungszentrum für Regenerative Therapien TU Dresden

nachricht The pyrenoid is a carbon-fixing liquid droplet
22.09.2017 | Max-Planck-Institut für Biochemie

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: The pyrenoid is a carbon-fixing liquid droplet

Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.

A warming planet

Im Focus: Highly precise wiring in the Cerebral Cortex

Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.

The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

Im Focus: Quantum Sensors Decipher Magnetic Ordering in a New Semiconducting Material

For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.

Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Rainbow colors reveal cell history: Uncovering β-cell heterogeneity

22.09.2017 | Life Sciences

Penn first in world to treat patient with new radiation technology

22.09.2017 | Medical Engineering

Calculating quietness

22.09.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>