Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scientists catch cold

11.02.2002


Snow may chill us through one or more receptors
© SPL


New skin receptor is the tip of the iceberg.

A snowball in the face or a chilly breeze around the ankles opens a molecular trap door in our skin’s nerve cells, two studies now show1,2. A third suggests that this, the first cold sensor to be identified, is just the tip of the iceberg3.

How sensory neurons detect a drop in temperature is very hard to study because it affects so many cell processes.



David Julius of the University of California, San Francisco, and his colleagues resorted to using menthol, which has the same effects on cold-sensitive nerves as a drop in temperature. "Technically it is much easier to use a chemical," says Julius.

Julius’s team took genes for a host of unknown receptors normally found on the surface of sensory nerve cells and inserted them into human kidney cells1. The confused kidney cells dutifully produced the receptors on their surface, which the team then exposed to menthol.

One receptor fitted the bill perfectly. It now has the catchy name cold- and menthol-sensitive receptor (CMR1); it is an ion channel. It opens in the presence of menthol, allowing potassium and calcium ions to flood into a nerve cell. Cooling has the same effect on it.

In a separate study, using different methods, Ardem Patapoutin at the Scripps research Institute in La Jolla, California identified another, possibly the same, cold receptor. While it’s too early to tell, Patapoutin says he’d "bet they’re the same".

A specific receptor for cold is a surprise, says Amy MacDermott a physiologist at Columbia University in New York. "It is totally unknown and extremely interesting," she says. Given the difficulties of studying the mechanisms of cold detection, Julius’s team "makes a very good case," she says.

Cold comfort

A single sensor doesn’t explain everything. Félix Viana, a physiologist at Miguel Herná¡ndez University in Alicante, Spain, and colleagues have found that cold-sensitive nerves have a unique number of the ordinary potassium ion channels that are common to all nerves. "This specialized blend of ion channels makes them sensitive to cooling," he says.

The Spanish group looked for a specific receptor but didn’t find one, says Viana. But "just because you don’t find something it doesn’t mean it’s not there," he admits.

The three studies present new and different explanations for how we detect cold. Physiologist Arthur Craig at Barrow Neurological Institute in Phoenix, Arizona, wonders whether a lone cold sensor would be diverse enough to explain the range of temperatures that our skin is sensitive to. Viana’s model accounts for this, he points out.

Like any well-engineered system, the body’s temperature-sensing network almost certainly has back-up mechanisms. Says Craig: "Biology is based on redundancy" - the teams are probably just working on different parts of the problem. "We can be sure that the biology is more complex than either study," he adds.

References

  1. McKemy, D. D., Neuhausser, W. M. & Julius, D. Identification of a cold receptor reveals a general role for TRP channels in thermosensation. Nature advance online publication, (2002).
  2. Peier, A. M. et al. A TRP channel that senses cold stimuli and menthol. Cell advance online publication, (2002).
  3. Viana, F., de la Peña, E. & Belmonte, C. Specificity of cold thermotransduction is determined by differential ionic channel expression. Nature Neuroscience advance online publication, (2002).


TOM CLARKE | © Nature News Service
Further information:
http://www.nature.com/nsu/020204/020204-14.html

More articles from Life Sciences:

nachricht Researchers develop eco-friendly, 4-in-1 catalyst
25.04.2017 | Brown University

nachricht Transfecting cells gently – the LZH presents a GNOME prototype at the Labvolution 2017
25.04.2017 | Laser Zentrum Hannover e.V.

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

NASA's Fermi catches gamma-ray flashes from tropical storms

25.04.2017 | Physics and Astronomy

Researchers invent process to make sustainable rubber, plastics

25.04.2017 | Materials Sciences

Transfecting cells gently – the LZH presents a GNOME prototype at the Labvolution 2017

25.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>