Navigation Links
A unique on-off switch for hormone production
Date:2/22/2012

After we sense a threat, our brain center responsible for responding goes into gear, setting off a chain of biochemical reactions leading to the release of cortisol from the adrenal glands.

Dr. Gil Levkowitz and his team in the Molecular Cell Biology Department have now revealed a new kind of ON-OFF switch in the brain for regulating the production of a main biochemical signal from the brain that stimulates cortisol release in the body. This finding, which was recently published in Neuron, may be relevant to research into a number of stress-related neurological disorders.

This signal is corticotropin releasing hormone (CRH). CRH is manufactured and stored in special neurons in the hypothalamus. Within this small brain region the danger is sensed, the information processed and the orders to go into stress-response mode are sent out. As soon as the CRH-containing neurons have depleted their supply of the hormone, they are already receiving the directive to produce more.

The research on zebrafish was performed in Levkowitz's lab and spearheaded by Dr. Liat Amir- Zilberstein together with Drs. Janna Blechman, Adriana Reuveny and Natalia Borodovsky, and Maayan Tahor. The team found that a protein called Otp is involved in several stages of CRH production. As well as directly activating the genes encoding CRH, it also regulates the production of two different receptors on the neurons' surface for receiving and relaying CRH production signals in effect, ON and OFF switches.

The team found that both receptors are encoded in a single gene. To get two receptors for the price of one, Otp regulates a gene-editing process known as alternative splicing, in which some of the elements in the sequence encoded in a gene can be "cut and pasted" to make slightly different "sentences." In this case, it generates two variants of a receptor called PAC1: The short version produces the ON receptor; the long version, containing an extra sequence, encodes the OFF receptor. The researchers found that as the threat passed and the supply of CRH was replenished, the ratio between the two types of PAC1 receptor on the neurons' surface gradually changed from more ON to mostly OFF. In collaboration with Drs Laure Bally-Cuif and William Norton of the Institute of Neurobiology Alfred Fessard at the Centre National de la Recherche Scientifique (CNRS) in France, the researchers showed that blocking the production of the long receptor variant causes an anxiety like behavior in zebrafish.

Together with Drs. Alon Chen and Yehezkel Sztainberg of the Neurobiology Department, Levkowitz's team found the same alternatively-spliced switch in mice. This conservation of the mechanism through the evolution of fish and mice implies that a similar means of turning CRH production on and off exists in the human brain.

Faulty switching mechanisms may play a role in a number of stress-related disorders. The action of the PAC1 receptor has recently been implicated in post-traumatic stress disorder, as well as in schizophrenia and depression. Malfunctions in alternative splicing have also been associated with epilepsy, mental retardation, bipolar disorder and autism.


'/>"/>

Contact: Yivsam Azgad
news@weizmann.ac.il
972-893-43856
Weizmann Institute of Science
Source:Eurekalert

Related biology news :

1. European researchers harness unique properties of boron to develop new drugs and diagnostics
2. Caltech geobiologists discover unique magnetic death star fossil
3. GUMC and Oak Ridge National Labs announce unique research partnership
4. NC State takes research lead in protecting Puerto Ricos unique freshwater fisheries
5. Unique transatlantic tie-up to understand the aging process
6. Researchers find pathway and enzyme unique to tularemia organism
7. Rots unique wood degrading machinery to be harnessed for better biofuels production
8. Weizmann Institute scientists develop a unique approach for splitting water into hydrogen and oxygen
9. Climate change threatens Lake Baikals unique biota
10. New DNA and RNA aptamers offer unique therapeutic advantages
11. Unique winter-hardy hibiscus has roots with AgriLife Research scientist in Vernon
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:2/7/2017)... , February 7, 2017 Ipsidy ... Solutions Corporation [OTC: IDGS], ("Ipsidy" or the "Company") a ... transaction processing services, is pleased to announce the following ... Effective January 31, 2017, Philip D. ... Directors, CEO and President.  An experienced payment industry professional ...
(Date:2/2/2017)... NEW YORK , Feb. 2, 2017  EyeLock ... has released a new white paper " What You ... The problem of ensuring user authenticity is a ... protect the authentication of users. However, traditional authentication schemes ... Biometric authentication offers an elegant ...
(Date:1/26/2017)... CITY , Jan. 26, 2017  Crossmatch, a ... unveiled a new solution aimed at combatting fraud, waste ... solution was introduced at the Action on Disaster Relief ... key meeting point for UN agencies and foreign assistance ... Fraud, waste and abuse are a largely unacknowledged ...
Breaking Biology News(10 mins):
(Date:2/24/2017)... ... ... Delpor, Inc. (Delpor), a biotechnology company focused on drug delivery, today announced ... for the further advancement of the company’s 3-month olanzapine product ( DLP-119 ). The ... therapeutic levels of olanzapine for a period of 3 months., “We are honored and ...
(Date:2/24/2017)... , Feb. 24, 2017 Symic Bio, ... developing a new category of therapeutics, announced today the ... SB-030 in peripheral artery disease. The trial will evaluate ... single-use therapeutic, in the reduction of restenosis following angioplasty. ... critical development milestone for SB-030," said Nathan Bachtell ...
(Date:2/24/2017)... Inc. (NASDAQ: CBPO) ("China Biologic" or the "Company"), a leading ... financial results for the fourth quarter and fiscal year of ... Total sales in the fourth quarter of ... 13.6% in USD terms to $77.6 million from $68.3 million ... profit increased by 13.3% to $46.8 million from $41.3 million ...
(Date:2/23/2017)... 2017 ... share data, unaudited)Three Months Ended December 31,Twelve Months Ended ... $           ... 89026%Aldurazyme Net Product Revenue 3539(10)%9498(4)%Kuvan ... Product Revenue  756025%297303(2)%Vimizim Net Product ...
Breaking Biology Technology: