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 How brains surrender to sleep
23.06.2017 | IMP - Forschungsinstitut für Molekulare Pathologie GmbH

nachricht A new technique isolates neuronal activity during memory consolidation
22.06.2017 | Spanish National Research Council (CSIC)

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Quantum thermometer or optical refrigerator?

23.06.2017 | Physics and Astronomy

A 100-year-old physics problem has been solved at EPFL

23.06.2017 | Physics and Astronomy

Equipping form with function

23.06.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>