Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Using RNA interference to tune gene activity in stem cells

03.02.2003


New method for the study and treatment of disease



The application of RNA interference (RNAi) to the study of mammalian biology and disease has the potential to revolutionize biomedical research and speed the development of novel therapeutic strategies.

A series of studies by Greg Hannon at Cold Spring Harbor Laboratory (CSHL) have revealed a great deal of information about the mechanism of RNAi, as well as how RNAi can be adapted for use in medical research. These and other studies led Science to name discoveries concerning RNAi the "Breakthrough of the Year" for 2002 among all of the sciences.


Now, researchers at CSHL have shown that RNAi can be used to set the level of gene activity in stem cells on "low," "medium," or "high."

The new study indicates that stable suppression of deleterious genes by RNAi--in which adult stem cells are isolated, modified ex vivo, and then re-introduced into the affected individual--might be an effective strategy for treating human disease.

The study, published in the February issue of Nature Genetics, focussed on the role of a tumor suppressor gene called p53 in a mouse model of lymphoma.

In the mouse model, forced expression of the Myc oncogene in B-cells causes the mice to develop B-cell lymphomas by 4 to 6 months of age. The scientists, led by Greg Hannon and his CSHL colleague, Scott Lowe, knew that completely deleting the p53 gene causes lymphomas to develop much sooner, and in a more aggressive, highly-invasive form, than lymphomas that develop when the p53 gene is present.

To test the effect of decreasing p53 to particular levels via RNA interference, the scientists reconstituted the blood cells of mice by first irradiating the animals to destroy their endogenous, bone marrow supply of hematopoietic stem cells, and then injected the mice with a fresh supply of hematopoietic stem cells that had been engineered through RNAi to produce low, medium, or high levels of p53.

The study showed that establishing different levels of p53 in B-cells by RNAi produces distinct forms of lymphoma. Similar to lymphomas that form in the absence of p53, lymphomas that formed in mice with low p53 levels developed rapidly (reaching terminal stage after 66 days, on average), infiltrated lung, liver, and spleen tissues, and showed little apoptosis or "programmed cell death."

In contrast, lymphomas that formed in mice with intermediate p53 levels developed less rapidly (reaching terminal stage after 95 days, on average), did not infiltrate lung, liver, or spleen tissues, and showed high levels of apoptosis. In mice with high B-cell p53 levels, lymphomas did not develop at an accelerated rate, and these mice did not experience decreased survival rates compared to control mice.

The study illustrates the ease with which RNAi "gene knockdowns" can be used to create a full range of mild to severe phenotypes (something that geneticists dream about), as well as the potential of RNAi in developing stem cell-based and other therapeutic strategies.

Along with a recent study by Hannon and his colleagues that demonstrated germline transmission of RNAi, the current study establishes RNAi as a convenient alternative to traditional, laborious, and less flexible homologous recombination-based gene knockout strategies for studying the effects of reduced gene expression in a wide variety of settings.

Peter Sherwood | EurekAlert!
Further information:
http://www.cshl.org/

More articles from Life Sciences:

nachricht Overlooked molecular machine in cell nucleus may hold key to treating aggressive leukemia
23.04.2019 | Cincinnati Children's Hospital Medical Center

nachricht Bacteria use their enemy -- phage -- for 'self-recognition'
23.04.2019 | Chinese Academy of Sciences Headquarters

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Quantum gas turns supersolid

Researchers led by Francesca Ferlaino from the University of Innsbruck and the Austrian Academy of Sciences report in Physical Review X on the observation of supersolid behavior in dipolar quantum gases of erbium and dysprosium. In the dysprosium gas these properties are unprecedentedly long-lived. This sets the stage for future investigations into the nature of this exotic phase of matter.

Supersolidity is a paradoxical state where the matter is both crystallized and superfluid. Predicted 50 years ago, such a counter-intuitive phase, featuring...

Im Focus: Explosion on Jupiter-sized star 10 times more powerful than ever seen on our sun

A stellar flare 10 times more powerful than anything seen on our sun has burst from an ultracool star almost the same size as Jupiter

  • Coolest and smallest star to produce a superflare found
  • Star is a tenth of the radius of our Sun
  • Researchers led by University of Warwick could only see...

Im Focus: Quantum simulation more stable than expected

A localization phenomenon boosts the accuracy of solving quantum many-body problems with quantum computers which are otherwise challenging for conventional computers. This brings such digital quantum simulation within reach on quantum devices available today.

Quantum computers promise to solve certain computational problems exponentially faster than any classical machine. “A particularly promising application is the...

Im Focus: Largest, fastest array of microscopic 'traffic cops' for optical communications

The technology could revolutionize how information travels through data centers and artificial intelligence networks

Engineers at the University of California, Berkeley have built a new photonic switch that can control the direction of light passing through optical fibers...

Im Focus: A long-distance relationship in femtoseconds

Physicists observe how electron-hole pairs drift apart at ultrafast speed, but still remain strongly bound.

Modern electronics relies on ultrafast charge motion on ever shorter length scales. Physicists from Regensburg and Gothenburg have now succeeded in resolving a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Revered mathematicians and computer scientists converge with 200 young researchers in Heidelberg!

17.04.2019 | Event News

First dust conference in the Central Asian part of the earth’s dust belt

15.04.2019 | Event News

Fraunhofer FHR at the IEEE Radar Conference 2019 in Boston, USA

09.04.2019 | Event News

 
Latest News

Marine Skin dives deeper for better monitoring

23.04.2019 | Information Technology

Geomagnetic jerks finally reproduced and explained

23.04.2019 | Earth Sciences

Overlooked molecular machine in cell nucleus may hold key to treating aggressive leukemia

23.04.2019 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>