Navigation Links
Who gives stem cells their marching orders?

Researchers from the Swiss Institute for Experimental Cancer Research (ISREC) have shown that a single gene involved in embryonic development is responsible for two seemingly contradictory activities -- maintaining stem cells after the embryo has implanted in the mother's uterus, and later providing cues to direct their differentiation in a coordinated fashion when the time is ripe.

The development of an embryo from a few seemingly identical stem cells is a truly awesome feat of nature. As they bathe in a chemical soup they've manufactured themselves, stem cells react to subtle changes in chemical concentration, moving apart and taking on distinct identities. The million-dollar question: How do these cells ?all initially the same, and exposed to the same environment ?end up acting in such different ways, and in so orchestrated a manner? Understanding the choreography involved in this mysterious cellular signaling dance is crucial to our ability to coax stem cells to grow into specific tissues outside the body. And it is also important if we are to understand and perhaps correct what goes wrong when the chemical signaling system goes awry and stem cells become cancerous.

Research has shown that the chemical soup in the developing embryo contains a protein factor called Nodal, a powerful "master chef" that controls the activity of a whole host of important regulatory genes. The ISREC group showed that embryos already need Nodal when they attach to the wall of the uterus, to expand their pool of stem cells, and to let individual cells know where they are with respect to their neighbors. However, to carry out these tasks, the Nodal protein must be cleaved by specific enzymes. The enzymes act as a sort of regulatory switch, increasing the stem cells' production of Nodal and preventing them from differentiating too early. Using mice engineered to carry an altered form of the protein, the ISREC group showed that if this switch is blocked, Nodal has the opp osite effect: it triggers a cascade of molecular signals which stimulate differentiation.

In an article appearing in the September issue of the journal Developmental Cell, the researchers explain how cleaved and uncleaved forms of the Nodal protein act together to let the stem cells know where to move and what to become, once the embryo has reached a critical size. "Whole blocks of chemical "programs" are triggered in a cascading fashion, with Nodal there to maintain the source of a concentration gradient," explains EPFL (Ecole Polytechnique Fédérale de Lausanne) professor Daniel Constam, lead researcher on the project. Constam adds that cells respond differently depending on the amount of time they have been exposed to the Nodal signal.

One hallmark of aggressive cancer cells is their unspecified nature, similar to that of embryonic stem cells. Constam and his colleagues think that the signaling pathways used by tumor cells to migrate and invade new territory might be similar to those used in the embryonic development of the organism. Recent research from Northwestern University seems to confirm this, showing that aggressive melanoma cells secrete the Nodal protein. Understanding the activity of this gene in embryonic development may hold the key to finding a way to control its activity in tumor cells. "We need to separate the aspects of Nodal function, and how this protein is regulated by the cell at the molecular level," says Constam. "The embryo holds the key to this understanding."
'"/>

Source:Ecole Polytechnique F茅d茅rale de Lausanne


Related biology news :

1. New imaging method gives early indication if brain cancer therapy is effective, U-M study shows
2. A little stress gives beneficial oomph! to immune system
3. Bionic arm gives amputee sense of touch
4. Gene thwarts some pathogens, gives access to others, could save crops
5. US woman gives birth to baby from worlds first frozen donor egg bank
6. Researcher gives hard thoughts on soft inheritance
7. Unique gene regulation gives chilly bugs survival advantage at bottom of the world
8. Thymus transplants gives hope to babies with fatal immune disease
9. Wisconsin scientists grow critical nerve cells
10. Spleen may be source of versatile stem cells
11. Researchers discover way to make cells in the eye sensitive to light

Post Your Comments:
*Name:
*Comment:
*Email:


(Date:3/28/2017)... March 28, 2017 The report ... (Camera, Monitors, Servers, Storage Devices), Software (Video Analytics, VMS), ... - Global Forecast to 2022", published by MarketsandMarkets, the ... and is projected to reach USD 75.64 Billion by ... 2022. The base year considered for the study is ...
(Date:3/24/2017)... 2017 Research and Markets has announced the ... & Trends - Industry Forecast to 2025" report to their ... The Global ... CAGR of around 15.1% over the next decade to reach approximately ... the market estimates and forecasts for all the given segments on ...
(Date:3/22/2017)... VILNIUS, Lithuania , March 21, 2017 /PRNewswire/ ... identification and object recognition technologies, today announced the ... development kit (SDK), which provides improved facial recognition ... safety cameras on a single computer. The new ... algorithms to improve accuracy, and it utilizes a ...
Breaking Biology News(10 mins):
(Date:6/15/2017)... ... 15, 2017 , ... Cybrexa Therapeutics, a start-up cancer therapeutics ... in the amount of $6 million. An investment vehicle affiliated with HighCape Partners, ... The Series B funding will enable Cybrexa to complete the build-out of its ...
(Date:6/15/2017)... ... 15, 2017 , ... DuPont Industrial Biosciences (DuPont) announced that ... Bloomberg’s 2017 Sustainable Business Summit: Seattle this Thursday, June 15, at ... a panel titled “Developing a Corporate Renewables Strategy.” , “Consumers want to ...
(Date:6/14/2017)... ... June 14, 2017 , ... The Thailand Board of ... that they’re co-hosting a delegation from Thailand at BIO 2017 in San Diego, ... gathering in the world, regroups more than 1,100 biotech companies, academic institutions, state ...
(Date:6/14/2017)... CA (PRWEB) , ... June 14, 2017 , ... ... cancer diagnostics and personalized medicine technology, today announced four new distribution agreements for ... over the cancer care cycle. The commercial agreements will make ClearID available immediately ...
Breaking Biology Technology: