Navigation Links
It must be important but what does it do? The strange case of UCP2
Date:8/17/2012

When uncoupling proteins are active, mitochondria produce heat instead of ATP. This may be useful under certain circumstances, such as when an animal is hibernating. But non-hibernating animals also have them. Particularly poorly understood is the uncoupling protein UCP2. Elena Pohl and colleagues at the University of Veterinary Medicine, Vienna, show that the protein occurs mainly in cells of the immune system. The group's highly provocative findings are published in the online journal PLOS ONE.

Mitochondria represent the powerhouses of the eukaryotic cell. They are able to use the primary product of the breakdown of sugars to generate a proton gradient across their inner membrane and to exploit this gradient to produce ATP, which drives cellular metabolism. The importance of mitochondria to higher life forms is clear from what happens when their function is blocked: many poisons, such as cyanide, are known to act in this manner.

In this light, the discovery in 1973 of a eukaryotic protein that dissipates the proton gradient without generating ATP was highly unexpected. When this protein, thermogenin, is active, mitochondria produce heat rather than ATP. We now know that thermogenin is merely one member of a family of so-called 'uncoupling proteins' that can use proton gradients to generate heat. The founder member of the family, thermogenin, has been renamed uncoupling protein 1 or UCP1 and is known to be important in helping animals keep warm during hibernation and for babies to maintain their body temperature. The actions of the other members of the family are less well understood. Particularly enigmatic is UCP2 but important clues to its function have now been provided by Anne Rupprecht and colleagues in the Institute of Physiology at the University of Veterinary Medicine, Vienna. Together with collaboration partners in Germany and Sweden, the researchers carefully examined the distribution of the UCP2 protein in mice. Their results showed clearly that UCP2 was preferentially expressed in cells related to the immune system and not, as generally believed, in neurons.

The implication was that UCP2 might somehow be involved in immune function. This surprising idea was tested by examining the change in UCP2 levels in T cells that were stimulated into action by a specific antigen. Stimulation indeed caused an increase in the amount of UCP2 in the cells. This was paralleled by increases in the concentrations of other proteins known to be produced in response to T-cell activation. When the cells were further stimulated seven and fourteen days later the amount of UCP2 increased although the amounts of the other proteins investigated did not.

It is attractive to speculate that the increase in UCP2 might be involved in signalling T-call stimulation but Pohl is quick to quash the notion. "Anne showed that the increase in UCP2 only starts a few hours after activation of T cells, while other events are seen much sooner. UCP2 thus arrives too late to be involved in stimulating the cells, so the increase must be related to overall metabolic changes in proliferating cells. This fits with our observation that UCP2 is not found in neurons, which no longer proliferate" In other words, although we still cannot be sure of the exact function of this intriguing protein, "at least we now know where to start looking!" And the finding that UCP2 is required by fast proliferating cells may have important consequences for the development of treatments for immune disorders, such as autoimmune and neurodegenerative diseases, and perhaps also for other diseases where cells divide rapidly, such as cancer.


'/>"/>

Contact: Elena Pohl
Elena.Pohl@vetmeduni.ac.at
43-650-366-3205
University of Veterinary Medicine -- Vienna
Source:Eurekalert

Related biology news :

1. Large, medically important class of proteins starts to yield its secrets
2. University of Miami-led study finds winds played important role in keeping oil away from S. Fla.
3. Wildfire and an example of its important link to the ecosystem
4. Overweight? New research explains how proper sleep is important for healthy weight
5. Geneticist develops tool to identify genes important in disease, tailoring individual treatment
6. Zip code as important as genetic code in childhood obesity
7. Misperception of weight is an important barrier to weight loss
8. Improved Authentication and Confidentiality Protection. ICAP Patent Brokerage Announces for Auction Important Patents in Data Encryption and Document Security
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/2/2016)... 2, 2016   The Weather Company , an IBM ... an industry-first capability in which consumers will be able to ... ask questions via voice or text and receive relevant information ... Marketers have long sought an advertising solution that ... be personal, relevant and valuable; and can scale across millions ...
(Date:6/1/2016)... NEW YORK , June 1, 2016 ... Biometric Technology in Election Administration and Criminal Identification to ... According to a recently released TechSci Research report, " ... Sector, By Region, Competition Forecast and Opportunities, 2011 - ... $ 24.8 billion by 2021, on account of growing ...
(Date:5/20/2016)... 2016  VoiceIt is excited to announce its ... By working together, VoiceIt and VoicePass will ... VoicePass take slightly different approaches to voice biometrics, ... and usability. ... partnership. "This marketing and technology partnership ...
Breaking Biology News(10 mins):
(Date:6/24/2016)... 24, 2016 Epic Sciences unveiled a ... susceptible to PARP inhibitors by targeting homologous recombination ... The new test has already been incorporated into ... cancer types. Over 230 clinical trials ... pathways, including PARP, ATM, ATR, DNA-PK and WEE-1. ...
(Date:6/23/2016)... ... June 23, 2016 , ... ... announce the launch of their brand, UP4™ Probiotics, into Target stores nationwide. The ... is proud to add Target to its list of well-respected retailers. This list ...
(Date:6/23/2016)... HOUSTON , June 23, 2016 ... agreement with the Cy-Fair Sports Association to serve ... of the agreement, Houston Methodist Willowbrook will provide ... education and connectivity with association coaches, volunteers, athletes ... partner with the Cy-Fair Sports Association and to ...
(Date:6/23/2016)... June 23, 2016   EpiBiome , a precision ... million in debt financing from Silicon Valley Bank (SVB). ... and to advance its drug development efforts, as well ... "SVB has been an incredible strategic partner ... a traditional bank would provide," said Dr. Aeron ...
Breaking Biology Technology: