Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researchers find local environment directly influences adult stem cell reservoirs

26.01.2005


Using the common fruit fly, researchers at UT Southwestern Medical Center have discovered that an intricate set of signals released by stem cells’ surroundings governs their maintenance.



These findings, available online and in today’s issue of Current Biology, will aid stem cell researchers in understanding and potentially manipulating the delicate environments that promote adult stem cell formation, said Dr. Dennis McKearin, associate professor of molecular biology and associate dean for the Medical Scientist Training Program at UT Southwestern and senior author of the study. "We want to understand the biochemistry behind stem cells that distinguishes them from other types of cells," Dr. McKearin said. "This work aids in understanding general stem cell biology."

The reproductive system of the female fruit fly, as in humans, contains a reservoir of adult stem cells. When the stem cells divide, they create two daughter cells, each with a distinct fate. One daughter travels away from the reservoir, divides further, and eventually becomes the egg and ’nurse’ cells, which nourish the egg.


The other daughter stays near the other stem cells and is influenced by the local environment to remain a stem cell, thereby maintaining the stem cell population. Dr. McKearin’s research shows that within the local environment, or niche, of the stem cell population, stromal cells, the non-stem cells that surround and attach to stem cells, release signals that are received and processed by stem cells and the daughters remaining in the niche. These molecular signals block certain genes from becoming active in the remaining stem cell daughters, preventing them from becoming any other kind of cell.

Genes controlling differentiation are turned off in some stem cell daughters but turned on in others, which move too far away to be influenced. Thus they develop into the egg and nurse cells. The success of this cell-to-cell communication is crucial. When the signals from the stromal cells are blocked, the stem cell population is gradually lost. When the signals are on all the time, or specific genes in the daughter cells are mutated, every daughter cell acts like a stem cell and the future eggs are lost.

"That stem cells are maintained by blocking gene expression suggests that the microenvironment, or niche, captures the cells and prevents them from differentiating," Dr. McKearin said. "Cells that are poised to differentiate do not, simply because of their niche."

Dr. McKearin said that in addition to their influence on stem cells, local environments or niches may influence the spread of cancer. "Specific types of cancer often metastasize to specific other organs," he said. "For example, prostate cancer cells that respond to certain growth factors may metastasize to bone, but not liver, because they can respond to external factors in the bone niche, but not the liver niche."

The other contributor to this study is Dr. Dahua Chen, instructor in molecular biology at UT Southwestern and lead author.

The study was funded by the National Institutes of Health.

Megha Satyanarayana | EurekAlert!
Further information:
http://www.utsouthwestern.edu

More articles from Life Sciences:

nachricht Clock stars: Astrocytes keep time for brain, behavior
27.03.2017 | Washington University in St. Louis

nachricht Cryo-electron microscopy achieves unprecedented resolution using new computational methods
24.03.2017 | DOE/Lawrence Berkeley National Laboratory

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

Im Focus: Researchers Imitate Molecular Crowding in Cells

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Electrical 'switch' in brain's capillary network monitors activity and controls blood flow

27.03.2017 | Health and Medicine

Clock stars: Astrocytes keep time for brain, behavior

27.03.2017 | Life Sciences

Sun's impact on climate change quantified for first time

27.03.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>