Navigation Links
Discovery suggests why stem cells run through stop signs

Everyone knows that stem cells are controversial. Many people know that stem cells can grow into virtually any cell type found in the body, from a red blood cell to a muscle cell to a brain cell. But no one really knows why stem cells continue to divide and renew themselves long after the point where other cells stop dividing.

Now scientists at Northwestern University and the University of Washington offer one of the first clues as to why stem cells ignore stop signs in the cell cycle: a special molecular mechanism has cut the brakes. The researchers found that tiny bits of genetic material called microRNAs are necessary for stem cell division to take place, suggesting that microRNAs shut off the signals that stop cell division in most other cells.

The findings were published online this week by the journal Nature. In the paper, the researchers also speculate that microRNAs may play a similar role in cancer cells, encouraging their proliferation. This speculation is supported by three other new papers published this week in Nature linking microRNAs to cancer.

According to authors Richard Carthew, Owen L. Coon Professor of Molecular Biology at Northwestern University, and Hannele Ruohola-Baker, professor of biochemistry at the University of Washington, microRNAs can regulate gene expression and give stem cells a green light to pass from the normal stop phase to the stage in which they begin replicating their DNA for later division.

In their work, Carthew and Ruohola-Baker focused on fruit flies, which have approximately 80 types of microRNAs. They genetically modified stem cells from the fruit flies' ovaries and studied how many egg chambers the mutant stem cells produced as compared to normal stem cells. The production rate in the mutant cells fell over the course of 12 days, and the researchers concluded it was because the mutant stem cells were no longer dividing.

Without the microRNAs at work, the brakes were applied to the cell division of the mutant stem cells, just like ordinary cells. The cellular brake (in this case a protein called Dacapo, a fruit fly homologue of a human tumor suppressor) kept the stem cells from proliferating.

"Determining which of the 80 microRNAs is responsible for deactivating the stop signal is the next step of our research," said Ruohola-Baker.

"The list of chores that microRNAs do within cells keeps growing in new and surprising ways," added Carthew. "This latest discovery with stem cell division makes us wonder if microRNAs also control division of other types of cells such as cancer cells."

Other authors on the Nature paper are Kenji Nakahara of Northwestern University and Karin Fischer, Steve Hatfield and Halyna Shcherbata of the University of Washington.


'"/>

Source:Northwestern University


Related biology news :

1. Fundamental Finding Yields Insight into Stem Cells, Cancer; Opens Door to Drug Discovery
2. Discovery of key proteins shape could lead to improved bacterial pneumonia vaccine
3. UCSD Discovery Shows How Embryonic Stem Cells Perform Quality Control Inspections
4. Discovery Could Lead To Novel Approaches In HIV Treatment
5. Discovery Promises Simpler Therapy for Sickle Cell Disease
6. Discovery may lead to better Candidiasis drug
7. Protein Discovery Could Unlock The Secret To Better TB Treatment
8. Discovery clarifies role of peptide in biological clock
9. Eliminate Data Analysis Bottlenecks in Drug Discovery
10. Discovery of New Dopamine Action May Yield Alternative Psychiatric Drugs
11. Discovery could be key to bioterrorism defense
Post Your Comments:
*Name:
*Comment:
*Email:


(Date:4/17/2017)... Florida , April 17, 2017 NXT-ID, ... technology company, announces the filing of its 2016 Annual Report on ... and Exchange Commission. ... on Form 10-K is available in the Investor Relations section of ... as on the SEC,s website at http://www.sec.gov . ...
(Date:4/11/2017)... N.Y. , April 11, 2017 ... fingerprints, but researchers at the New York University ... College of Engineering have found that partial similarities ... security systems used in mobile phones and other ... thought. The vulnerability lies in the ...
(Date:4/5/2017)... -- KEY FINDINGS The global market for ... of 25.76% during the forecast period of 2017-2025. The ... the growth of the stem cell market. ... INSIGHTS The global stem cell market is segmented on ... stem cell market of the product is segmented into ...
Breaking Biology News(10 mins):
(Date:6/26/2017)... ... June 26, 2017 , ... Third Wave Bioactives, LLC announces the addition ... on leading new business development and ensuring quality customer experience. , Brett ... ingredient industry in technical, marketing and sales roles. “Brett’s background working with customers and ...
(Date:6/23/2017)... , ... June 23, 2017 , ... Ken Hanson, a ... of Physik Instrumente USA, have been selected as this year’s recipients of two top ... two have been invited along with other honorees to accept their awards at a ...
(Date:6/22/2017)... ... June 21, 2017 , ... Building on the success of the inaugural RAADfest ... the very latest developments in radical life extension. RAADfest combines cutting edge science presented ... empowerment of personal development, making it the largest most comprehensive and inclusive super longevity ...
(Date:6/22/2017)... ... ... The first human cell line HeLa, established in 1951, has entered cell ... human cell lines with HeLa cells were published. Until recently, cross-contamination and misidentification of ... associated with dramatic consequences for research. , In this educational webinar, which is ...
Breaking Biology Technology: