Featured Research

from universities, journals, and other organizations

Cellular switches: From the RNA world to the 'modern' protein world

Date:
February 9, 2012
Source:
Heidelberg University
Summary:
Scientists have discovered the molecular mechanism of a G protein family. G proteins play a central role in cellular signal processing. They are described as molecular switches that oscillate between 'on' and 'off', regulated by effectors. Biochemists have now gained fundamental insights into the mechanics of these switches.

Heidelberg scientists have discovered the molecular mechanism of a G protein family.

Related Articles


G proteins play a central role in cellular signal processing. They are described as molecular switches that oscillate between 'on' and 'off', regulated by effectors. Biochemists at Heidelberg University have now gained fundamental insights into the mechanics of these switches. By studying the flagella, the organelles of locomotion in bacteria, researchers were able to identify an effector that turns a specific G protein 'off'. They succeeded in visualising this process through X-ray crystallography. Their research results also provide insight into the evolution from the world of RNA to the "modern" world of proteins.

Bacteria need to be mobile to react to environmental changes, and in the case of pathogens, to reach the site of infection. Flagella are the organelles of locomotion in bacteria and the tiniest motors in the biosphere. When cells divide, the exact position of the new flagellum needs to be determined each time. The G protein FlhF is responsible for that task. FlhF is a molecular switch that apparently needed no effectors. "In our study, however, we identified a protein that assumes the effector role and were able to describe its mode of action, thereby fundamentally altering this previously held view," explains Prof. Dr. Irmgard Sinning of the Heidelberg University Biochemistry Center.

The G protein FlhF, together with a signal sequence binding protein (SRP54) and its receptor (FtsY), constitutes the ancient family of SRP-GTPases, which consists solely of these three proteins and is responsible for the transport of proteins in or through a biological membrane. In all known organisms, SRP54 and FtsY regulate the transport of proteins using the signal recognition particle (SRP). Although the SRP system is already well understood, it was recently demonstrated that the protein SRP54 and the receptor FtsY interact with the SRP RNA in a way reminiscent of FlhF and its newly discovered effector.

"Our study of the G protein FlhF not only offers an explanation for the FlhF effector complex, it also integrates this knowledge into a general concept of SRP-GTPase activation through RNA or proteins," says Dr. Gert Bange of the Heidelberg University Biochemistry Center. "We used FlhF to demonstrate how the 'modern' protein world replaced the original RNA world by means of a strikingly simple modification." The results of the research were published in "Nature Structural & Molecular Biology."


Story Source:

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


Journal Reference:

  1. Gert Bange, Nico Kόmmerer, Przemyslaw Grudnik, Robert Lindner, Georg Petzold, Dieter Kressler, Ed Hurt, Klemens Wild, Irmgard Sinning. Structural basis for the molecular evolution of SRP-GTPase activation by protein. Nature Structural & Molecular Biology, 2011; 18 (12): 1376 DOI: 10.1038/nsmb.2141

Cite This Page:

Heidelberg University. "Cellular switches: From the RNA world to the 'modern' protein world." ScienceDaily. ScienceDaily, 9 February 2012. <www.sciencedaily.com/releases/2012/02/120209101607.htm>.
Heidelberg University. (2012, February 9). Cellular switches: From the RNA world to the 'modern' protein world. ScienceDaily. Retrieved February 27, 2015 from www.sciencedaily.com/releases/2012/02/120209101607.htm
Heidelberg University. "Cellular switches: From the RNA world to the 'modern' protein world." ScienceDaily. www.sciencedaily.com/releases/2012/02/120209101607.htm (accessed February 27, 2015).

Share This


More From ScienceDaily



More Plants & Animals News

Friday, February 27, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Cherries, Snap Peas and More Tasty Spring Produce

Cherries, Snap Peas and More Tasty Spring Produce

Buzz60 (Feb. 27, 2015) — From sweet cherries to sugar snap peas, spring is the peak season for some of the tastiest and healthiest produce. Krystin Goodwin (@Krystingoodwin) has the best seasonal fruits and veggies to spring in to good health! Video provided by Buzz60
Powered by NewsLook.com
The Best Foods to Battle Stress

The Best Foods to Battle Stress

Buzz60 (Feb. 26, 2015) — If you&apos;re dealing with anxiety, there are a few foods that can help. Krystin Goodwin (@krystingoodwin) has the best foods to tame stress. Video provided by Buzz60
Powered by NewsLook.com
The Amazon Keeps Its Green Thanks To The Sahara Desert

The Amazon Keeps Its Green Thanks To The Sahara Desert

Newsy (Feb. 25, 2015) — Satellite data shows the Amazon rainforest supports its lush flora with a little help from Sahara Desert dust. Video provided by Newsy
Powered by NewsLook.com
Mayor Says District of Columbia to Go Ahead With Pot Legalization

Mayor Says District of Columbia to Go Ahead With Pot Legalization

Reuters - News Video Online (Feb. 25, 2015) — Washington&apos;s mayor says the District of Columbia will move forward with marijuana legalization, despite pushback from Congress. Rough Cut (no reporter narration). Video provided by Reuters
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