Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scientists Unravel Clue in Cortisol Production

26.04.2007
When a person’s under stress or injured, the adrenal gland releases cortisol to help restore the body’s functions to normal. But the hormone’s effects are many and varied, lowering the activity of the immune system, helping create memories with short-term exposure, while impairing learning if there’s too much for too long. Given the variety of its effects,understanding how cortisol is made is essential to producing medications that can alter its production.

Scientists at the Georgia Institute of Technology have discovered an important step in cortisol production, finding that although the output of the hormone is continuous, the molecular production is cyclic in nature – involving a rhythmic binding and unbinding of a protein essential to its production. The research, which increases understanding of how the brain and the endocrine system work together to regulate health, appears in the February issue of the journal Molecular Endocrinology.

Turning cholesterol into the stress hormone cortisol involves many reactions and begins when the hypothalamus sends a signal to the adrenal glands. Proteins then flood into the nucleus to bind to the DNA, creating the gene CYP 17. What happens next is well understood; CYP 17, along with a battery of other enzymes, transforms cholesterol into cortisol. But what isn’t understood is how this protein binding creates CYP 17, or which proteins are important. So, graduate students Eric Dammer and Adam Leon, along with Marion Sewer, assistant professor in Georgia Tech’s School of Biology, decided to model the events that occur after the adrenal gland receives the signal.

One of the things the signal does is cause adrenal cells to increase their production of cyclic AMP (cAMP), a chemical that encourages proteins to interact. So they began by causing the cells to make more cAMP. Then as the proteins assembled on the DNA, they tested the cells at different intervals in order to get a snapshot of which proteins were interacting, both with each other and the DNA and in which order this occurred. Then they mutated the proteins to stop them from fulfilling their roles.

... more about:
»CYP »Cortisol »DNA »SF-1 »adrenal »gland

"One of the best ways to try and figure out the function of a protein or a gene is to get rid of it or mutate it so that it’s not acting normally. Then you compare it with one that is acting normally,” said Sewer.

In this study, they focused on a protein known as steriodogenic factor 1 (SF-1), which is essential for making all steroid hormones. Researchers were interested in discovering what events have to occur in order for SF-1 to bind to DNA.

The first thing they found was that because DNA is so tightly packed in the nucleus, SF-1 can’t bind to it until it’s unpacked by a group of proteins. Once that happens, SF-1 binds to the genes, beginning the process that makes CYP 17 and ultimately cortisol. But it’s not a continuous process, they found.

"Once SF-1 binds, it leaves. A few minutes later other proteins come in and condense the DNA,” said Sewer. “After that SF-1 binds again, then leaves, and the proteins cause the DNA to contract again.”

This cycle goes on as long as the adrenal gland is receiving the signal.

"Even though you get a sustained production of cortisol, the actual molecular events that happen in the nucleus are dynamic,” said Sewer. “It’s an extremely complex series of events that starts within minutes of the adrenal gland receiving the signal. Without all these transient binding events, the adrenal gland fails to produce optimal levels of cortisol.”

Next the team will investigate how small molecules – ligands – regulate cortisol production by binding to SF-1 and controlling the receptor’s ability to bind to DNA.

This research was supported by the National Institutes of Health, the National Science Foundation and the Georgia Cancer Coalition.

David Terraso | EurekAlert!
Further information:
http://www.gatech.edu

Further reports about: CYP Cortisol DNA SF-1 adrenal gland

More articles from Life Sciences:

nachricht The birth of a new protein
20.10.2017 | University of Arizona

nachricht Building New Moss Factories
20.10.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Terahertz spectroscopy goes nano

20.10.2017 | Information Technology

Strange but true: Turning a material upside down can sometimes make it softer

20.10.2017 | Materials Sciences

NRL clarifies valley polarization for electronic and optoelectronic technologies

20.10.2017 | Interdisciplinary Research

VideoLinks
B2B-VideoLinks
More VideoLinks >>>