Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researchers identify a key regulator for skin stem cells

09.10.2006
By turning on a single gene, researchers can prevent skin stem cells from maturing into the three types of adult skin cells -- epidermal, sebaceous and hair cells. They say this finding could have important implications for scientists trying to grow stem cells in the lab, for both research and potential therapies.

As researchers seek ways to manipulate stem cells, which have the ability to differentiate into multiple types of tissues, one challenge they face is maintaining the stem cells in their immature state. The newly identified repressor switch could provide part of the answer.

Led by Howard Hughes Medical Institute investigator Elaine Fuchs, the researchers published discovery of this regulator, known as Tcf3, in an article in the October 6, 2006, issue of the journal Cell. Other co-authors on the paper include Hoang Nguyen and Michael Rendl in the Fuchs laboratory at The Rockefeller University.

Tcf3 is a transcription factor, a protein that controls the activity of a collection of genes in order to coordinate their action. In earlier studies, Fuchs and her colleagues had found that the gene for Tcf3 is activated in a region of the adult hair follicle called the bulge, where stem cells are expected to be. They also knew from studies in other laboratories that a relative of Tcf3, called Tcf4, appears to be important for the development of the intestine.

... more about:
»Embryonic »Tcf3 »follicle

The researchers reasoned that if Tcf3 plays a role in maintaining adult follicle cells, it would also be present in embryonic skin, which consists mainly of stem cells. When they analyzed the epidermis of embryonic mice, they found that theTcf3 gene was, indeed, active in the embryonic skin stem cells.

The researchers next sought to pinpoint which genes Tcf3 controls. They genetically engineered a mouse in which they could switch the Tcf3 gene on at will in skin cells. They then used DNA microarrays to analyze which genes were affected when Tcf3 was activated. Microarrays, also known as "gene chips," enable scientists to determine the activity of thousands of genes at once.

"When we compared the list of genes that Tcf3 repressed or induced, we found that it was very similar to the genes expressed when the skin is embryonic," said Nguyen. "So, by turning on Tcf3, we were essentially reverting the postnatal skin cells to be more similar to embryonic skin cells. The genetic program induced by Tcf3 is also very similar to that seen in bulge cells, where adult stem cells are thought to reside," she said.

In particular, the researchers found that Tcf3 repressed members of a gene family called PPAR, which themselves produce key transcription factors that promote skin stem cells to differentiate into epidermal and sebaceous gland cells.

The biggest surprise, said Fuchs, came when the researchers analyzed how switching on Tcf3 affected the differentiation of embryonic skin stem cells. They found that activating the gene in mice blocked differentiation of all three types of mature skin cells -- epidermal, sebaceous, and hair follicle. "We've known for some time that Tcf3 can operate with a co-factor called â-catenin and initiate skin stem cells to make hair follicles. But we hadn't realized that Tcf3 could act on its own to keep skin stem cells in an undifferentiated state," Fuchs explained. â-Catenin is stabilized in response to Wnt signaling, which Fuchs' team earlier showed plays a key role in the ability of stem cells to make hair.

Fuchs said that Wnt signaling has been shown to play a role in many different types of stem cells in the body. The discovery that one of â-catenin's partners, Tcf3, can repress genes in the absence of a Wnt signal may be important in understanding how these transcription factors work in stem cells. In further studies, Fuchs and her colleagues plan to study in more detail how Tcf proteins govern stem cell biology.

Jennifer Michalowski | EurekAlert!
Further information:
http://www.hhmi.org

Further reports about: Embryonic Tcf3 follicle

More articles from Life Sciences:

nachricht Discovery of a Key Regulatory Gene in Cardiac Valve Formation
24.05.2017 | Universität Basel

nachricht Carcinogenic soot particles from GDI engines
24.05.2017 | Empa - Eidgenössische Materialprüfungs- und Forschungsanstalt

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

Im Focus: Using graphene to create quantum bits

In the race to produce a quantum computer, a number of projects are seeking a way to create quantum bits -- or qubits -- that are stable, meaning they are not much affected by changes in their environment. This normally needs highly nonlinear non-dissipative elements capable of functioning at very low temperatures.

In pursuit of this goal, researchers at EPFL's Laboratory of Photonics and Quantum Measurements LPQM (STI/SB), have investigated a nonlinear graphene-based...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

Physicists discover mechanism behind granular capillary effect

24.05.2017 | Physics and Astronomy

Measured for the first time: Direction of light waves changed by quantum effect

24.05.2017 | Physics and Astronomy

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>