Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Ronin recruits protein 'allies' to sustain embryonic stem cell growth

25.06.2010
Ronin, crucial to the self-renewal of embryonic stem cells, and a co-regulator called Hcf-1, binds to a small strand of DNA called a hyperconserved enhancer element to control a gene "program" that stimulates growth of the stem cells and may even play a role in cancer, said a group of researchers led by Baylor College of Medicine in a current report in the journal Genes and Development.

Dr. Thomas P. Zwaka, associate professor in the Stem Cells and Regenerative Medicine (STaR) Center at BCM and others in his laboratory first identified Ronin and its role in maintaining stem cells in their undifferentiated state. Now he and his colleagues from the University of Houston, The University of Texas MD Anderson Cancer Center and Massachusetts Institute of Technology (MIT) in Cambridge, Mass., have identified the tiny strand of DNA that enables the protein with its co-regulator Hcf-1 to maintain the rapid growth that characterizes embryonic stems cells.

Finding this small DNA strand required determining the genetic sequence of the site to which Ronin binds in the genome, he said. They used high tech, extremely rapid sequencing methods (high throughput, massively parallel sequencing) to identify the appropriate sequences and determine their genetic code. They analyzed 866 potential binding sites and found a similar motif in 844.

As chance would have it, this genetic sequence had been previously identified in a pure bioinformatics study of genetic sequences that are present in most mammalian species. Because such sequences are conserved throughout evolution, they are believed to play a fundamental role in cellular processes. In a list of 100 most conserved genetic regions, this DNA sequence ranked fourth in frequency. In this case, researchers believe that the small DNA strand bound to a transcription factor that they had not identified. (A transcription factor governs translation of the DNA message in a gene into RNA, which can then be used by the cell's machinery as a template for a protein.)

"Ronin is that factor," said Zwaka. "Ronin binds to the 'hyperconserved enhancer element' sequence and then recruits Hcf-1. Only if it recruits Hcf-1 do we get activation of the special gene growth program."

With this highly conserved enhancer element, the Ronin/Hcf-1 combination controls a specific growth program of genes that are required in the early formation of an embryo, stem cells and maybe in some tumor cells, he said.

"When you look at the target genes of Ronin/Hcf-1, all are in the category of protein metabolism," he said.

Embryonic stem cells are characterized by rapid growth and renewal.

"Graduate students complain that they have to split and feed the cells every day. If you don't supply them with fresh medium, they die because they use it all up. It is important to understand what underlies this prolific growth," he said.

Understanding that could help scientists growth the cells better in the laboratory. Cancer growth, in many ways, simulates that of embryonic stem cells, he said. Understanding the growth program made up of 1,000 or more genes regulated by Ronin/Hcf-1 could help determine new strategies for fighting tumors.

Others who took part in this research include Dr. Marion Dejosez of BCM, Dr. Stuart S. Levine, Garrett M. Frampton, Warren Whyte and Dr. Richard A. Young of MIT, Sabrina A. Stratton and Dr. Michelle C. Barton of MD Anderson and Dr. Preethi H. Gunaratne of UH.

Funding for this work came from the National Institutes of Health, the Diana Helis Henry Medical Research Foundation and the Huffington Foundation.

When the embargo lifts, this report will be available at http://genesdev.cshlp.org/.

For more information on basic science research at Baylor College of Medicine, go to www.bcm.edu/fromthelab or www.bcm.edu/news.

Glenna Picton | EurekAlert!
Further information:
http://www.bcm.edu/news

More articles from Life Sciences:

nachricht Could this protein protect people against coronary artery disease?
17.11.2017 | University of North Carolina Health Care

nachricht Microbial resident enables beetles to feed on a leafy diet
17.11.2017 | Max-Planck-Institut für chemische Ökologie

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 “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

Im Focus: Wrinkles give heat a jolt in pillared graphene

Rice University researchers test 3-D carbon nanostructures' thermal transport abilities

Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

NASA detects solar flare pulses at Sun and Earth

17.11.2017 | Physics and Astronomy

NIST scientists discover how to switch liver cancer cell growth from 2-D to 3-D structures

17.11.2017 | Health and Medicine

The importance of biodiversity in forests could increase due to climate change

17.11.2017 | Studies and Analyses

VideoLinks
B2B-VideoLinks
More VideoLinks >>>