Featured Research

from universities, journals, and other organizations

Unfolded proteins collapse when exposed to heat, crowded environments

Date:
March 24, 2014
Source:
University of Zurich
Summary:
Not only folded proteins fulfill important functions in the human body; unfolded or intrinsically disordered proteins (IDPs) likewise assume major tasks. Researchers have observed how molecular forces influence protein structure. The unfolded proteins become smaller when exposed to elevated temperatures and density stress.

Not only folded proteins fulfill important functions in the human body; unfolded or intrinsically disordered proteins (IDPs) likewise assume major tasks. Researchers at the University of Zurich have observed how molecular forces influence protein structure. The unfolded proteins become smaller when exposed to elevated temperatures and density stress.

Proteins are important molecules in our body and they fulfill a broad range of functions. For instance as enzymes they help to release energy from food and as muscle proteins they assist with motion. As antibodies they are involved in immune defense and as hormone receptors in signal transduction in cells. Until only recently it was assumed that all proteins take on a clearly defined three-dimensional structure -- i.e. they fold in order to be able to assume these functions. Surprisingly, it has been shown that many important proteins occur as unfolded coils. Researchers seek to establish how these disordered proteins are capable at all of assuming highly complex functions.

Ben Schuler's research group from the Institute of Biochemistry of the University of Zurich has now established that an increase in temperature leads to folded proteins collapsing and becoming smaller. Other environmental factors can trigger the same effect. The crowded environments inside cells lead to the proteins shrinking. As these proteins interact with other molecules in the body and bring other proteins together, understanding of these processes is essential "as they play a major role in many processes in our body, for instance in the onset of cancer," comments study coordinator Ben Schuler.

Measurements using the "molecular ruler"

"The fact that unfolded proteins shrink at higher temperatures is an indication that cell water does indeed play an important role as to the spatial organization eventually adopted by the molecules," comments Schuler with regard to the impact of temperature on protein structure. For their studies the biophysicists use what is known as single-molecule spectroscopy. Small color probes in the protein enable the observation of changes with an accuracy of more than one millionth of a millimetre. With this "molecular yardstick" it is possible to measure how molecular forces impact protein structure.

With computer simulations the researchers have mimicked the behavior of disordered proteins. They want to use them in future for more accurate predictions of their properties and functions.

Correcting test tube results

That's why it's important, according to Schuler, to monitor the proteins not only in the test tube but also in the organism. "This takes into account the fact that it is very crowded on the molecular level in our body as enormous numbers of biomolecules are crammed into a very small space in our cells," says Schuler. The biochemists have mimicked this "molecular crowding" and observed that in this environment disordered proteins shrink, too.

Given these results many experiments may have to be revisited as the spatial organization of the molecules in the organism could differ considerably from that in the test tube according to the biochemist from the University of Zurich. "We have, therefore, developed a theoretical analytical method to predict the effects of molecular crowding." In a next step the researchers plan to apply these findings to measurements taken directly in living cells.


Story Source:

The above story is based on materials provided by University of Zurich. Note: Materials may be edited for content and length.


Journal References:

  1. A. Soranno, I. Koenig, M. B. Borgia, H. Hofmann, F. Zosel, D. Nettels, B. Schuler. Single-molecule spectroscopy reveals polymer effects of disordered proteins in crowded environments. Proceedings of the National Academy of Sciences, 2014; DOI: 10.1073/pnas.1322611111
  2. R. Wuttke, H. Hofmann, D. Nettels, M. B. Borgia, J. Mittal, R. B. Best, B. Schuler. Temperature-dependent solvation modulates the dimensions of disordered proteins. Proceedings of the National Academy of Sciences, 2014; DOI: 10.1073/pnas.1313006111

Cite This Page:

University of Zurich. "Unfolded proteins collapse when exposed to heat, crowded environments." ScienceDaily. ScienceDaily, 24 March 2014. <www.sciencedaily.com/releases/2014/03/140324090252.htm>.
University of Zurich. (2014, March 24). Unfolded proteins collapse when exposed to heat, crowded environments. ScienceDaily. Retrieved October 20, 2014 from www.sciencedaily.com/releases/2014/03/140324090252.htm
University of Zurich. "Unfolded proteins collapse when exposed to heat, crowded environments." ScienceDaily. www.sciencedaily.com/releases/2014/03/140324090252.htm (accessed October 20, 2014).

Share This



More Plants & Animals News

Monday, October 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

White Lion Cubs Born in Belgrade Zoo

White Lion Cubs Born in Belgrade Zoo

AFP (Oct. 20, 2014) Two white lion cubs, an extremely rare subspecies of the African lion, were recently born at Belgrade Zoo. They are being bottle fed by zoo keepers after they were rejected by their mother after birth. Duration: 00:42 Video provided by AFP
Powered by NewsLook.com
Traditional Farming Methods Gaining Ground in Mali

Traditional Farming Methods Gaining Ground in Mali

AFP (Oct. 20, 2014) He is leading a one man agricultural revolution in Mali - Oumar Diatabe uses traditional farming methods to get the most out of his land and is teaching others across the country how to do the same. Duration: 01:44 Video provided by AFP
Powered by NewsLook.com
Goliath Spider Will Give You Nightmares

Goliath Spider Will Give You Nightmares

Buzz60 (Oct. 20, 2014) An entomologist stumbled upon a South American Goliath Birdeater. With a name like that, you know it's a terrifying creepy crawler. Sean Dowling (@SeanDowlingTV) has the details. Video provided by Buzz60
Powered by NewsLook.com
Hey, Doc! Sewage, Beer and Food Scraps Can Power Chevrolet’s Bi-Fuel Impala

Hey, Doc! Sewage, Beer and Food Scraps Can Power Chevrolet’s Bi-Fuel Impala

3BL Media (Oct. 20, 2014) Hey, Doc! Sewage, Beer and Food Scraps Can Power Chevrolet’s Bi-fuel Impala Video provided by 3BL
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins