Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Last of known genes identified in complex obesity syndrome

16.08.2004


By comparing three different species’ genomes and adding some good old-fashioned genetic analysis, scientists have uncovered the identity of the last of eight genes known to contribute to Bardet-Biedl syndrome, a rare disorder characterized by a combination of some otherwise common problems, including obesity, learning difficulties, diabetes and asthma.



The identification of the BBS3 gene ends the search for primary BBS-causing genes in families studied for years by a team of scientists from the United States, Canada and the United Kingdom. However, the scientists are still hunting for other, less obvious genetic influences in these families.

Writing in the Aug. 15 advance online section of Nature Genetics, the international team reports that BBS3 is actually a gene formerly known as ARL6. Importantly, ARL6 is the first BBS culprit to belong to a family of genes and proteins with a known function, opening the door to figuring out what’s really happening in people with the condition.


"We can use BBS3/ARL6 and its known function -- binding the molecule GTP -- as a great place to start to unravel the details of the other BBS proteins," says Nicholas Katsanis, Ph.D., assistant professor in Johns Hopkins’ McKusick-Nathans Institute of Genetic Medicine. "And understanding BBS may provide important insight for understanding obesity, learning difficulties and other BBS-related problems that also appear in the general population."

Family studies had managed to link BBS3 to a region of chromosome 3, but getting to the gene had proven challenging. Now, by taking advantage of their recent discovery that faulty cellular structures called cilia are behind the problems seen in BBS patients, the researchers were able to zero in on the disease-causing gene.

Cilia are found on many different types of cells and can either act like antennae, sensing important signals, or help push fluid or mucous around, such as in the lungs. Some BBS-related mutations seem to disrupt the scaffolding upon which cilia are built, but others may cause ciliary dysfunction in other ways, perhaps preventing or misdirecting the shuttling of materials along the cilia.

By searching a database of cilia-related genes compiled by comparing three species’ genomes -- a bacterium, a plant, and a human [see May 15, 2004, news release] -- the researchers found three possibilities in the right region of chromosome 3. Next, they determined the genetic sequences of those three genes in four families with BBS. One of the genes, ARL6, had a different, critical mutation in each of the families, the researchers found.

"ARL6 is the first member of its larger gene family to be tied to any disease," says Katsanis. "While not much is known about ARL6 specifically, we know quite a bit about its relatives, so we know which regions of ARL6 are crucial for the protein’s correct function. The mutations in these families wouldn’t let the protein work properly."

ARL6 is a member of a class of proteins that bind GTP, or guanosine triphosphate -- a class given the obvious title of GTP-binding proteins. GTP-binding is a critical step in a wide variety of signaling "cascades" that pass along messages and instructions inside cells -- such as to open or close the cell’s entry points or to trigger relocation of "freight" within the cell.

"That this type of molecule could cause BBS is particularly intriguing," says Katsanis.

In additional experiments using the worm C. elegans, the researchers proved that ARL6 normally functions only in cilia, suggesting it might relay specific signals in that part of the cell. The next step is to figure out exactly what those signals might be.

"We don’t know what its message is, but because we know that it binds GTP, we have some ideas of where to start looking," says Katsanis.

Joanna Downer | EurekAlert!
Further information:
http://www.jhmi.edu

More articles from Life Sciences:

nachricht Cancer diagnosis: no more needles?
25.05.2018 | Christian-Albrechts-Universität zu Kiel

nachricht Less is more? Gene switch for healthy aging found
25.05.2018 | Leibniz-Institut für Alternsforschung - Fritz-Lipmann-Institut e.V. (FLI)

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Powerful IT security for the car of the future – research alliance develops new approaches

The more electronics steer, accelerate and brake cars, the more important it is to protect them against cyber-attacks. That is why 15 partners from industry and academia will work together over the next three years on new approaches to IT security in self-driving cars. The joint project goes by the name Security For Connected, Autonomous Cars (SecForCARs) and has funding of €7.2 million from the German Federal Ministry of Education and Research. Infineon is leading the project.

Vehicles already offer diverse communication interfaces and more and more automated functions, such as distance and lane-keeping assist systems. At the same...

Im Focus: Molecular switch will facilitate the development of pioneering electro-optical devices

A research team led by physicists at the Technical University of Munich (TUM) has developed molecular nanoswitches that can be toggled between two structurally different states using an applied voltage. They can serve as the basis for a pioneering class of devices that could replace silicon-based components with organic molecules.

The development of new electronic technologies drives the incessant reduction of functional component sizes. In the context of an international collaborative...

Im Focus: LZH showcases laser material processing of tomorrow at the LASYS 2018

At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.

At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...

Im Focus: Self-illuminating pixels for a new display generation

There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?

At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...

Im Focus: Explanation for puzzling quantum oscillations has been found

So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics

Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

In focus: Climate adapted plants

25.05.2018 | Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

 
Latest News

In focus: Climate adapted plants

25.05.2018 | Event News

Flow probes from the 3D printer

25.05.2018 | Machine Engineering

Less is more? Gene switch for healthy aging found

25.05.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>