Featured Research

from universities, journals, and other organizations

How cells degrade aberrant membrane proteins

Date:
July 13, 2012
Source:
Heidelberg, Universität
Summary:
Researchers have achieved unexpected insights into the process of how damaged proteins are degraded within cells. Their work focused on the function of a special protease. This enzyme can hydrolyze peptide bonds in the plane of cellular membranes, a site where such water-requiring reactions commonly do not occur. The scientists can now show that this unusual protease recognizes and degrades aberrant proteins directly in the membrane.

Researchers from Heidelberg University's Center for Molecular Biology (ZMBH) have achieved unexpected insights into the process of how damaged proteins are degraded within cells. Their work focused on the function of a special protease. This enzyme can hydrolyse peptide bonds in the plane of cellular membranes, a site where such water-requiring reactions commonly do not occur. The scientists working with Dr. Marius Lemberg could now show that this unusual protease recognises and degrades aberrant proteins directly in the membrane.

Related Articles


The findings were published online in Molecular Cell.

When the research team around Dr. Lemberg started its work on a member of these special proteases they predicted by computational approaches that this enzyme would be active. However, they still faced the challenge to experimentally determine the physiological substrates. "The existing knowledge about relatives from the so-called rhomboid protease family did not help us in our quest for the molecules processed by the enzyme we discovered," says Dr. Lemberg. Unlike all rhomboid proteases that had been studied so far, the new rhomboid localises to the Endoplasmic Reticulum (ER), the site in the cell where new membrane proteins are produced.

The breakthrough came after the researchers observed that the ER rhomboid protease is increasingly needed during protein folding stress. Proteins are produced as long chains of amino acids that have to correctly fold into a three-dimensional structure to fulfil their function. Especially when accumulating, misfolded proteins can severely damage cells and are known to cause impairments such as Alzheimer's and Parkinson's disease.

"We now have revealed that the ER rhomboid protease cleaves aberrant membrane proteins within their membrane anchor," says Dr. Lemberg. Furthermore, the scientists demonstrated that this protease cooperates directly with components of the so-called ER-associated degradation (ERAD) pathway to dispose of the faulty protein. According to Dr. Lemberg, these new insights now provide the basis for a molecular understanding of how membrane proteins that make up a large fraction of cellular proteins are extracted from these membranes for degradation without getting into each other's way.

The junior research group of Dr. Lemberg is part of the DKFZ-ZMBH Alliance -- the strategic cooperation between the German Cancer Research Center (DKFZ) and the Heidelberg University's Center for Molecular Biology (ZMBH) -- as well as of the interdisciplinary Network Aging Research (NAR) at Ruperto Carola. The group receives funding from the Baden-Württemberg Foundation.


Story Source:

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


Journal Reference:

  1. Lina Fleig, Nina Bergbold, Priyanka Sahasrabudhe, Beate Geiger, Lejla Kaltak, Marius K. Lemberg. Ubiquitin-Dependent Intramembrane Rhomboid Protease Promotes ERAD of Membrane Proteins. Mol. Cell, July 12, 2012 DOI: 10.1016/j.molcel.2012.06.008

Cite This Page:

Heidelberg, Universität. "How cells degrade aberrant membrane proteins." ScienceDaily. ScienceDaily, 13 July 2012. <www.sciencedaily.com/releases/2012/07/120713095250.htm>.
Heidelberg, Universität. (2012, July 13). How cells degrade aberrant membrane proteins. ScienceDaily. Retrieved November 24, 2014 from www.sciencedaily.com/releases/2012/07/120713095250.htm
Heidelberg, Universität. "How cells degrade aberrant membrane proteins." ScienceDaily. www.sciencedaily.com/releases/2012/07/120713095250.htm (accessed November 24, 2014).

Share This


More From ScienceDaily



More Plants & Animals News

Monday, November 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Ebola-Hit Sierra Leone's Late Cocoa Leaves Bitter Taste

Ebola-Hit Sierra Leone's Late Cocoa Leaves Bitter Taste

AFP (Nov. 23, 2014) — The arable district of Kenema in Sierra Leone -- at the centre of the Ebola outbreak in May -- has been under quarantine for three months as the cocoa harvest comes in. Duration: 01:32 Video provided by AFP
Powered by NewsLook.com
Anglerfish Rarely Seen In Its Habitat Will Haunt You

Anglerfish Rarely Seen In Its Habitat Will Haunt You

Newsy (Nov. 22, 2014) — For the first time Monterey Bay Aquarium recorded a video of the elusive, creepy and rarely seen anglerfish. Video provided by Newsy
Powered by NewsLook.com
Birds Around the World Take Flight

Birds Around the World Take Flight

Reuters - Light News Video Online (Nov. 22, 2014) — An imperial eagle equipped with a camera spreads its wings over London. It's just one of the many birds making headlines in this week's "animal roundup". Jillian Kitchener reports. Video provided by Reuters
Powered by NewsLook.com
Could Your Genes Be The Reason You're Single?

Could Your Genes Be The Reason You're Single?

Newsy (Nov. 21, 2014) — Researchers in Beijing discovered a gene called 5-HTA1, and carriers are reportedly 20 percent more likely to be single. Video provided by Newsy
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