Navigation Links
Researchers Purify Protein That Could Regulate Male Hormones

Researchers at University of North Carolina at Chapel Hill have managed to purify a protein and have shown that it can affect gene activity by modifying a molecular pathway// that was previously thought to be permanent.

The findings, published today (May 5) in the journal Cell, also show that the new protein plays a role in gene activation mediated by androgen receptor, a protein that responds to androgen hormones. In this regard, the novel protein may figure in the development of prostate cancer. Androgens, particularly testosterone and dihydrotestosterone, determine male secondary sex characteristics and stimulate prostate cell growth. Lowering androgen levels usually can make prostate cancers shrink or grow more slowly.

In the study, the researchers said the new protein called JHDM2A, like the protein they reported on in the journal Nature in December 2005, is able to remove a methyl group from histone H3, one of four histone proteins bound to all genes.

"Human genes are so tightly compact within the nucleus that if the DNA of a single cell were unwound and stretched, it would be a line of about two meters in length. Histones are necessary to package the DNA so that it fits inside a cell's nucleus," said senior author Dr. Yi Zhang, professor of biochemistry and biophysics at UNC's School of Medicine and the university's first Howard Hughes Medical Institute investigator.

Zhang also is a member of the UNC Lineberger Comprehensive Cancer Center.

Because histones are so intimately associated with DNA, even slight chemical alterations of these proteins can have profound effects on nearby genes. Depending on their precise location and how many methyl groups are added, the presence of alterations can either turn on or turn off a gene.

In the study, Zhang learned that the JHDM2A specifically removes methyl-groups from lysine 9 of histone H3. "The important thing is that H3K9 demethylation has been linked to tran scription silencing, turning genes off. So that led us to pay attention to this protein's role in reversing whatever function K9 methylation might have," Zhang said.

In their experiments, the researchers learned that consistent with reversing a marker of gene silencing (H3K9 methylation), the protein functions as a co-activator – in this case, a co-activator for the androgen receptor target genes.

Using human tissue cultures, including prostate cells, Zhang and his colleagues found that over-expression of JHDM2A greatly reduced H3K9 methylation level and led to upregulation, or switching on, of androgen receptor target genes. In contrast, when methylation was increased, the gene was silenced – switched off.

It remains unclear for how many different human genes JHDM2A is a primary regulator. According to Zhang, the new findings indicate that the protein will provide another tool to enlist in studies of gene expression regulation. "Given the androgen receptor link, we're now trying to identify the downstream target genes, as well as its role in prostate cancer," he said.

"Theoretically, this protein is a very important tool for gene expression studies. Practically, it provides a potential target for prostate cancer because of its enzymatic activity. And it is enzymatic activity that's the favorite target of drug development."

Leslie H. Lang
University of North Carolina School of Medicine
Source: Eurekalert


Related medicine news :

1. Researchers urge caution in using ear tube surgery
2. Researchers Scale to assess the Severity of Epilepsy in Kids
3. Researchers trick Alzheimers Enzyme
4. Researchers find new HIV hiding place
5. New Hair in 15 Days Could Now Be A Possibility Say Researchers
6. Researchers developed world’s smallest toothbrus
7. Researchers discover receptor cells that can cause epilepsy
8. 15 Anti-SARS Drugs Identified By China-Europe Team of Researchers
9. Researchers reversed the process of memory loss
10. Researchers Identify Key Gene That May Help Brain Treatment
11. Researchers Discover Protein That Causes Malaria
Post Your Comments:

(Date:11/30/2015)... ... 2015 , ... Third Molar SEO , one of ... launched a sleek, mobile-ready and user-centric redesigned website. , Vivek Srivastava, founder and ... the benefits that its SEO services provide to dentists and why Third Molar ...
(Date:11/30/2015)... ... 01, 2015 , ... The National Association of Professional Women (NAPW) ... the Year Circle. She is recognized with this prestigious distinction for leadership in estate ... boasting more than 850,000 members and over 200 operating Local Chapters. , “I’m pleased ...
(Date:11/30/2015)... ... November 30, 2015 , ... Until now, the St. Louis Fetal ... MOMS (Management of Myelomeningocele Study) trial. One of these exclusion criteria was a BMI ... of 18.5 to 24.9 is considered normal, 25 - 29.9 is overweight and above ...
(Date:11/30/2015)... ... November 30, 2015 , ... An extensive ... is specialized and only includes chiropractic clinics in the US. , The team ... alternative health practitioner when back pain sets in. When people are experiencing back ...
(Date:11/30/2015)... ... November 30, 2015 , ... On Saturday, October 24th, 2015, at the ... annual fundraising event, a 5K walk known as “Making Strides Against Breast Cancer”. Patients ... which is also located in Battle Creek, joined in for this campaign that sought ...
Breaking Medicine News(10 mins):
(Date:11/30/2015)... 30, 2015  QT Vascular Ltd., together with its ... its subsidiaries, TriReme Medical LLC and Quattro Vascular Pte. ... the design, assembly and distribution of advanced therapeutic solutions ... pleased to announce that a three-judge panel of ... for the Federal Circuit ("Federal Circuit") has unanimously granted ...
(Date:11/30/2015)... 30, 2015   Royal Philips  (NYSE: ... of Radiology Solutions, a fully integrated, consultative approach ... customized, data-driven practice management approaches that combine imaging ... practices improve care delivery and reduce costs. Making ... of North America Annual Meeting (RSNA) in ...
(Date:11/30/2015)... Nautilus Medical Inc. today announced worldwide availability of MatrixRay, ... The release of MatrixRay to the entire medical healthcare ... America) in Chicago - the ... --> --> MatrixRay is the first ... worldwide via a peer-to-peer exchange network of physicians and ...
Breaking Medicine Technology: