Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Mice Cloned from Olfactory Cells

16.02.2004


Researchers have successfully cloned a mouse using mature olfactory neurons as the genetic donor. The scientists credit the idea for the experiments to Woody Allen whose classic comedy Sleeper depicted scientists who try to clone a dead dictator from his nose.


The images are of a newborn mouse cloned from an olfactory sensory neuron that had been marked with a genetic change so that it would be green under fluorescent light. Here you see on the right, a green cloned pup and in the upper left a normal non-green newborn mouse for comparison.



The current study aims to answer longstanding questions about the developmental potential of mature cells. In doing their experiments, the researchers were seeking to determine whether a single mature olfactory neuron, when introduced into an egg, or oocyte, depleted of its nucleus, could revert to an undifferentiated state in which it could give rise to an adult mouse possessing the full range of olfactory receptors.

Indeed, the resulting mice exhibited an array of well organized odorant receptors that were indistinguishable from those of normal mice, the researchers reported on February 15, 2004, in an article published in an advance online publication in the journal Nature. The research was performed in the laboratories of Rudolf Jaenisch at the Whitehead Institute for Biomedical Research at MIT, and Richard Axel, a Howard Hughes Medical Institute investigator at Columbia University. Co-lead authors on the paper were Kevin Eggan in Jaenisch’s laboratory and Kristin Baldwin in Axel’s laboratory.


“Our study demonstrates for the first time that animals can be derived from the nucleus of mature neurons following transfer into the oocyte. Because the cloned animals are normal, our experiment also shows that [some] brain functions do not involve genetic alterations of the neuron’s genome,” said Jaenisch.

According to the researchers, previous cloning efforts had failed to clone animals from the nuclei of any mature “post-mitotic” cells such as neurons - that is, those that had ceased dividing to produce new cells.

A central question, said the scientists, was whether mature cells had undergone certain irreversible genetic processes, such as gene rearrangements, that would prevent them from reprogramming their nuclei to allow totipotent development. These processes might interfere with the cell’s ability to become totipotent, a property of certain stem cells that permits them to differentiate into any cell type

The researchers chose olfactory neurons as the source of genetic material because previous research had suggested that these cells might undergo gene rearrangements during development. Whatever the underlying process involved in generating their spectacular diversity, olfactory neurons are distinguished by their ability to randomly express any one of some 1,500 diverse odor receptor genes. Such genes give rise to the protein receptors on the surface of the neurons that detect specific chemical odorants.

In their efforts, the researchers in Axel’s laboratory generated mice with olfactory sensory neurons tagged using genetic marker molecules. Using standard cloning techniques, the researchers in Jaenisch’s laboratory then isolated individual neurons, removed nuclei from the tagged cells and introduced the nuclei into mouse eggs from which the nuclei had been removed. When these eggs were introduced into surrogate mother mice, the resulting offspring proved viable and fertile. Furthermore, they exhibited the normal pattern of odorant-receptor gene expression and organization of odorant receptor genes.

According to Axel, the cloning achievement eliminates one potential mechanism and narrows the possible ways in which a cell chooses one of thousands of receptor genes. The findings also demonstrate that the developmental changes are reversible.

Axel said that the cloning technique should be broadly applicable. “From a mechanistic point of view, it’s very important to be able to investigate whether irreversible changes in the DNA accompany development, differentiation and maturation,” he said. “This approach, although technologically demanding, affords an opportunity to detect those changes that are irreversible in virtually all cells.”

Axel emphasized that their experiments had no application to the newly announced achievement by South Korean scientists in cloning human embryos. “Our experiments were performed largely to address problems in neuronal diversity,” he said.

Jim Keeley | HHMI
Further information:
http://www.hhmi.org/news/axel3.html

More articles from Life Sciences:

nachricht The birth of a new protein
20.10.2017 | University of Arizona

nachricht Building New Moss Factories
20.10.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Terahertz spectroscopy goes nano

20.10.2017 | Information Technology

Strange but true: Turning a material upside down can sometimes make it softer

20.10.2017 | Materials Sciences

NRL clarifies valley polarization for electronic and optoelectronic technologies

20.10.2017 | Interdisciplinary Research

VideoLinks
B2B-VideoLinks
More VideoLinks >>>