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

HOUSTON -- (June 25, 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.


Contact: Glenna Picton
Baylor College of Medicine

Related biology news :

1. New mediator of smoking recruits
2. Protein chatter linked to cancer activation
3. Scientists link fragile X tremor/ataxia syndrome to binding protein in RNA
4. Researchers identify proteins involved in new neurodegenerative syndrome
5. Low levels of key protein may indicate pancreatic cancer risk
6. Structure of 450 million year old protein reveals evolutions steps
7. Scientists retrace evolution with first atomic structure of an ancient protein
8. Specific brain protein required for nerve cell connections to form and function
9. NIH awards researcher $1.5 million new innovator grant for fruit-fly studies of prion proteins
10. Interacting protein theory awaits test from new neutron analysis tools
11. Depression, aging, and proteins made by a virus may all play role in heart disease
Post Your Comments:
(Date:11/20/2015)... 20, 2015 NXTD ) ("NXT-ID" ... the growing mobile commerce market and creator of the ... , was recently interviewed on The RedChip Money ... this weekend on Bloomberg Europe , Bloomberg Asia, ... --> NXTD ) ("NXT-ID" or the "Company"), a ...
(Date:11/17/2015)... , November 17, 2015 Paris ...   --> Paris from 17 th ... DERMALOG, the biometrics innovation leader, has invented the first combined ... on the same scanning surface. Until now two different scanners ... one scanner can capture both on the same surface. ...
(Date:11/12/2015)... , Nov. 12, 2015  A golden retriever that ... muscular dystrophy (DMD) has provided a new lead for ... Hospital, the Broad Institute of MIT and Harvard and ... . Cell, pinpoints a ... "escape" the disease,s effects. The Boston Children,s lab of ...
Breaking Biology News(10 mins):
(Date:11/25/2015)... , Nov. 25, 2015  Neurocrine Biosciences, Inc. ... Gorman , President and CEO of Neurocrine Biosciences, will ... Conference in New York . ... visit the website approximately 5 minutes prior to the ... replay of the presentation will be available on the ...
(Date:11/25/2015)... ... 2015 , ... A long-standing partnership between the Academy of ... formalized with the signing of a Memorandum of Understanding. , AMA Executive Director ... Minter and Capt. Albert Glenn Tuesday, November 24, 2015, at AMA Headquarters in ...
(Date:11/25/2015)... 25, 2015 The Global ... a professional and in-depth study on the current ... (Logo: ) , The ... including definitions, classifications, applications and industry chain structure. ... international markets including development trends, competitive landscape analysis, ...
(Date:11/24/2015)... LUMPUR, Malaysia , Nov. 24, 2015 /PRNewswire/ ... global contract research organisation (CRO) market. The trend ... result in lower margins but higher volume share ... increased capacity and scale, however, margins in the ... Research Organisation (CRO) Market ( ), ...
Breaking Biology Technology: