Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Mouse genetic model for spongiform brain diseases

31.01.2003


Cornell geneticist Teresa Gunn displays a mahoganoid mutant mouse, a possible animal model for brain disease in humans.


Some mice with a genetic mutation for mahogany-colored coats also develop spongiform degeneration of brain tissue, similar to mad cow disease. Because of this oddity, the mice could be valuable animal models for human disorders, such as Parkinson’s and Alzheimer’s diseases, according to geneticists at Cornell and Stanford universities.

The surprising discovery in a mouse strain known to geneticists since the 1960s is reported in the latest issue of the journal Science (Jan. 31, 2003) by Teresa M. Gunn, Gregory S. Barsh and their collaborators as "Spongiform Degeneration in mahoganoid Mutant Mice."

"Just don’t call them mad mice," pleads Gunn, an assistant professor of genetics in Cornell’s College of Veterinary Medicine who began the research in Barsh’s laboratory at Stanford. "We do see the same kind of tissue degeneration -- with fluid-filled vacuoles, or holes, where the gray matter should be -- in BSE cattle with bovine spongiform encephalopathy and in these mutant mice. But the mice don’t have the same motor coordination problems as mad cows, and the condition is not lethal."



Rather, the mutant mice exhibit little more than a slight tremor when they begin to move, they live a normal life span for their species and are able to reproduce, Gunn says. Nor did the investigators find evidence of misshapen prion proteins (the cause of spongiform encephalopathies such as mad cow and mad elk diseases) in the mice, although they did see damage to the myelin sheaths around nerve cells. Among other distinguishing characteristics of the mutant mice are curly whiskers and slightly curly body hair, as well as the habit of clasping their hind feet together when lifted off the ground. Normal mice tend to splay their legs straight out when they are elevated, Gunn explains.

Furthermore, this form of neurodegeneration is not known to be contagious, Gunn says, noting: "A cat that eats a mahoganoid mutant mouse -- should one escape from the laboratory -- would not get spongiform encephalopathy."

The researchers were looking for effects that might be linked to mutations in pigmentation genes. They knew that a loss of function in the so-called Mahogunin gene causes a partial reduction in the amount of yellow pigment, so that the mice were left with only small patches of yellow hair on mostly black bodies. But they were surprised to learn that a complete loss of function in that gene produced all-black mice with brain neurodegeneration. Linkages between unusual pigmentation and neural defects are not unheard of in the animal world, Gunn adds, citing predominantly white dogs, such as Dalmatians, that sometimes are deaf.

As an animal model, the mahoganoid mutant mice probably will not be useful to study spongiform encephalopathies like mad cow disease, Gunn believes, because rogue prions are not the cause of the mouse condition. But as an example of defective ubiquitination -- a protein-related process involved in many neurodegenerative disorders, including Parkinson’s and Alzheimer’s diseases -- the mahogany-colored mice with spongy brains could have real value, according to the Cornell scientist.

And the mutant mouse probably isn’t patentable because it has a naturally occurring defect that the researchers did not create and because the mice already are commercially available. However, Gunn suggests, further work with the gene responsible for the neurodegenerative condition might result in patent applications.

Gunn credits Cornell undergraduate student Aaron F. Jolly for his research assistance in the study. Jolly is one of eight co-authors of the Science report. The study was supported, in part, by grants from the National Institutes of Health and the American Heart Association.

Roger Segelken | Cornell
Further information:
http://web.vet.cornell.edu/public/BioSci/new/vbs_ld.html

More articles from Life Sciences:

nachricht One step closer to reality
20.04.2018 | Max-Planck-Institut für Entwicklungsbiologie

nachricht The dark side of cichlid fish: from cannibal to caregiver
20.04.2018 | Veterinärmedizinische Universität Wien

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Spider silk key to new bone-fixing composite

University of Connecticut researchers have created a biodegradable composite made of silk fibers that can be used to repair broken load-bearing bones without the complications sometimes presented by other materials.

Repairing major load-bearing bones such as those in the leg can be a long and uncomfortable process.

Im Focus: Writing and deleting magnets with lasers

Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.

Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...

Im Focus: Gamma-ray flashes from plasma filaments

Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.

The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...

Im Focus: Basel researchers succeed in cultivating cartilage from stem cells

Stable joint cartilage can be produced from adult stem cells originating from bone marrow. This is made possible by inducing specific molecular processes occurring during embryonic cartilage formation, as researchers from the University and University Hospital of Basel report in the scientific journal PNAS.

Certain mesenchymal stem/stromal cells from the bone marrow of adults are considered extremely promising for skeletal tissue regeneration. These adult stem...

Im Focus: Like a wedge in a hinge

Researchers lay groundwork to tailor drugs for new targets in cancer therapy

In the fight against cancer, scientists are developing new drugs to hit tumor cells at so far unused weak points. Such a “sore spot” is the protein complex...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

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

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

IWOLIA: A conference bringing together German Industrie 4.0 and French Industrie du Futur

09.04.2018 | Event News

 
Latest News

Magnetic nano-imaging on a table top

20.04.2018 | Physics and Astronomy

Start of work for the world's largest electric truck

20.04.2018 | Interdisciplinary Research

Atoms may hum a tune from grand cosmic symphony

20.04.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>