Navigation Links
Novel enzyme offers new look at gene regulation

Scientists at the University of North Carolina at Chapel Hill have purified a novel protein and have shown it can alter gene activity by reversing a molecular modification previously thought permanent.

In the study, the authors showed that a protein called JHDM1A is able to remove a methyl group from histone H3, one of four histone proteins bound to all genes. Until just last year, the addition of a methyl group to a histone had been regarded as irreversible.

"That histones can become methylated has been known for over three decades, and just now we're learning that those methyl groups can also be removed," said Dr. Yi Zhang, the lead author.

Zhang is professor of biochemistry and biophysics at UNC's School of Medicine and the university's first Howard Hughes Medical Institute investigator. He also is a member of the UNC Lineberger Comprehensive Cancer Center.

The new study is now online in the journal Nature.

"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," said Zhang. "Histones are necessary to package the DNA so that it fits inside a cell's nucleus."

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

The first enzyme to remove methyl groups from histones, or histone demethylase, was identified last year. This was a breakthrough in the study of histone modifications, but Zhang thought pieces of the puzzle were still missing.

"We hypothesized that there were more demethylase enzymes out there for two reasons," Zhang said. "For one, the previous demethylase identified, called LSD1, could not remove a chain of three methyl groups from a histone, or a trimethyl group. Secon dly, common baker's yeast does not have LSD1, although it does have proteins adding methyl groups to histones."

Zhang devised a biochemical strategy to isolate proteins that could remove methyl from histones inside a test tube. The result was the identification of a novel protein, JHDM1A, named for JmjC histone demethylase 1A. A similar protein exists in baker's yeast and has the potential to remove trimethyl groups.

JmjC is only a section of the entire JHDM1A protein, but is required for its demethylase activity. The authors showed that disruption of JmjC prevents JHDM1A from removing histone methyl groups.

Importantly, the JmjC section of JHDM1A, or "JmjC domain," can be found in other proteins, even when the proteins share little else in common. Database searches predict more than 100 total proteins found in organisms as diverse as bacteria and man contain the JmjC domain. This suggests that many other proteins may act similarly to methyl groups from histones or other proteins.

The implications of the new findings are as diverse as the proteins that contain a JmjC domain. For example, hair loss occurs in individuals with mutations in the JmjC domain of a protein called "hairless," possibly due to defects in the appropriate removal of histone methyl groups.

"Given the large numbers of JmjC domain-containing proteins that exist in diverse organisms ranging from yeast to human, our discovery will keep many people in the field busy for the years to come," said Zhang.


'"/>

Source:University of North Carolina School of Medicine


Related biology news :

1. Novel Asthma Study Shows Multiple Genetic Input Required; Single-gene Solution Shot Down
2. Novel technology detects human DNA mutations
3. Novel antiviral technology inhibits RSV infection in mice
4. Novel Enzyme Shows Potential As An Anti-HIV Target
5. Novel Therapy Tested in Mice Could Chase Away Cat Allergies
6. Discovery Could Lead To Novel Approaches In HIV Treatment
7. Novel ultrafast laser detection of cancer cells also may improve understanding of stem cells
8. Research Using Mouse Models Reveals A Novel Key Player In The Initiation Of Colon Cancer
9. Novel gene-silencing nanoparticles shown to inhibit Ewings sarcoma
10. Novel live reporting system to track cells
11. Field of beams - Novel system uses polarized light pulses to reveal crop health
Post Your Comments:
*Name:
*Comment:
*Email:


(Date:4/14/2016)... AVIV, Israel , April 14, 2016 ... Behavioral Authentication and Malware Detection, today announced the appointment ... already assumed the new role. Goldwerger,s leadership ... BioCatch, on the heels of the deployment of its ... addition, BioCatch,s behavioral biometric technology, which discerns unique cognitive ...
(Date:3/31/2016)...  Genomics firm Nabsys has completed a financial  restructuring ... , M.D., who returned to the company in October ... team, including Chief Technology Officer, John Oliver , ... and Vice President of Software and Informatics, Michael ... Dr. Bready served as CEO of Nabsys from 2005-2014 ...
(Date:3/22/2016)... 22, 2016 According ... Market for Consumer Industry by Type (Image, Motion, ... (Communication & IT, Entertainment, Home Appliances, & ... to 2022", published by MarketsandMarkets, the market ... reach USD 26.76 Billion by 2022, at ...
Breaking Biology News(10 mins):
(Date:6/24/2016)... 24, 2016  Regular discussions on a range of subjects ... the two entities said Poloz. Speaking at a ... , he pointed to the country,s inflation target, which ... "In certain areas ... have common economic goals, why not sit down and address ...
(Date:6/24/2016)... NC (PRWEB) , ... June 24, 2016 , ... Researchers ... the most commonly-identified miRNAs in people with peritoneal or pleural mesothelioma. Their findings are ... to read it now. , Diagnostic biomarkers are signposts in the blood, lung ...
(Date:6/23/2016)... June 23, 2016   Boston Biomedical , ... compounds designed to target cancer stemness pathways, announced ... granted Orphan Drug Designation from the U.S. Food ... gastric cancer, including gastroesophageal junction (GEJ) cancer. Napabucasin ... to inhibit cancer stemness pathways by targeting STAT3, ...
(Date:6/23/2016)... 2016 Houston Methodist Willowbrook Hospital has ... Association to serve as their official health care ... Willowbrook will provide sponsorship support, athletic training services, ... coaches, volunteers, athletes and families. "We ... Association and to bring Houston Methodist quality services ...
Breaking Biology Technology: