Worm gene could be key to developing obesity treatment

February 13, 2017, Monash University
Monash University Associate Professor Roger Pocock. Credit: Monash University

Monash University and Danish researchers have discovered a gene in worms that could help break the cycle of overeating and under-exercising that can lead to obesity.

The team has discovered a gene that triggers a feeling of fullness, as well as the need to sleep after eating. A similar gene is found in people, opening up the potential to develop a drug that could help control obesity by reducing appetite and increasing the desire for exercise.

The team, led by Associate Professor Roger Pocock at the Monash Biomedicine Discovery Institute and his colleagues at the University of Copenhagan, published their results today in the Proceedings of the National Academy of Sciences, a prestigious US journal.

Associate Professor Pocock and his team discovered a gene, encoding a transcription factor called ETS-5, which controls signals from the brain to the intestines. Associate Professor Pocock explained that when the intestine had stored enough fat, the brain would receive the message to stop moving, effectively putting the worm to sleep.

"When animals are malnourished they seek out food by roaming their environment. When they're well fed they have no need to roam, and when they're fully sated they enter a sleep-like state," Associate Professor Pocock said.

The researchers studied Caenorhabditis elegans, or the roundworm, because of the comparative simplicity of its brain—it has just 302 neurons and 8,000 synapses, or neuron-to-neuron connections, all of which have been mapped. Compare this with the human brain which has billions of neurons, more than 160,000 kilometres of biological wiring, and 100 trillion synapses.

Associate Professor Pocock said the roundworm and humans share up to 80 per cent of their genes, as well as around half of all the known genes which are involved in human diseases.

"Because roundworms share so many genes with humans they are a great model system to investigate and gain a better understanding of processes like metabolism as well as diseases in humans," he said.

The researchers discovered the role of the transcription factor ETS-5 by analysing single neurons within the brain of the worm, monitoring its response to food. They found that—much like mammals including humans—a diet that supports growth elicits a different response in worms compared with low quality food. In mammals, a diet loaded with fats and sugars stimulates overfeeding, leading to obesity. When fed on low quality food the worms roamed in search of better nutrition.

The discovery of ETS-5 is the first time a gene regulatory molecule of this type, and potential drug target, has been implicated in the brain-intestinal control of eating and activity, according to Associate Professor Pocock.

"The ETS family of genes is present in humans and has previously been linked to obesity regulation. Now that we've learned this gene family controls food intake through a feedback system to the brain, it represents a credible drug target for the treatment of ," he said.

Explore further: Scientists find brain hormone that triggers fat burning

More information: The ETS-5 transcription factor regulates activity states in Caenorhabditis elegans by controlling satiety, PNAS, www.pnas.org/cgi/doi/10.1073/pnas.1610673114

Related Stories

Scientists find brain hormone that triggers fat burning

January 27, 2017
Biologists at The Scripps Research Institute (TSRI) have identified a brain hormone that appears to trigger fat burning in the gut. Their findings in animal models could have implications for future pharmaceutical development.

What causes sleepiness when sickness strikes

January 19, 2017
It's well known that humans and other animals are fatigued and sleepy when sick, but it's a microscopic roundworm that's providing an explanation of how that occurs, according to a study from researchers at the Perelman School ...

Right combination of sugars regulates brain development in worms

September 19, 2013
If the development of our nervous system is disturbed, we risk developing serious neurological diseases, impairing our sensory systems, movement control or cognitive functions. This is true for all organisms with a well-developed ...

Variations in gene expression may underlie increased food intake in obesity

April 11, 2016
Large-scale genetic studies have identified a number of variations in genes that increase an individual's susceptibility to obesity.

Mutations in FTO and dopamine receptor genes increase risk of obesity and diabetes

October 17, 2016
In the development of obesity and diabetes, signals from the brain play an important role. Here an important neurotransmitter is dopamine. DZD scientists from Tübingen and Munich, together with Swedish and American colleagues, ...

Recommended for you

Identifying Crohn's disease risk factors in the Ashkenazi Jewish population

May 25, 2018
It is estimated that one in three individuals of Ashkenazi Jewish (AJ) descent carry mutations that increase their risk for certain genetic diseases. For instance, Crohn's, a highly heritable inflammatory bowel disease, is ...

How do insects survive on a sugary diet?

May 25, 2018
There's a reason parents tell their kids to lay off the sugar: too much isn't good for you.

Regulatory mutations missed in standard genetic screening lead to congenital diseases

May 25, 2018
Researchers have identified a type of genetic aberration to be the cause of certain neurodevelopmental disorders and congenital diseases, such as autism and congenital heart disease, which are undetectable by conventional ...

New chromosome study can lead to personalised counselling of pregnant women

May 25, 2018
Foetuses with a so-called new balanced chromosomal aberration have a higher risk of developing brain disorders such as autism and mental retardation than previously anticipated. The risk is 20 per cent for foetuses with these ...

New findings on autism-related disorder

May 24, 2018
In a study published today in Nature, Marc Bühler and his group at the Friedrich Miescher Institute for Biomedical Research (FMI) have taken a major step forward in elucidating the mechanisms underlying a disorder known ...

Genome study presents new way to track historical demographics of US populations

May 24, 2018
Sharon Browning of the University of Washington and colleagues developed a method to estimate historical effective population size, which is the number of individuals who pass on their genes to the next generation, to reveal ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.