Featured Research

from universities, journals, and other organizations

How Mitochondria Get Their Membranes Bent

Date:
July 9, 2009
Source:
Goethe University Frankfurt
Summary:
Underneath their smooth surface mitochondria harbor an elaborately folded inner membrane. It holds a multitude of bottleneck like invaginations, which expand into elongated cavities. Now researchers have identified two proteins linked in an antagonistic manner that are relevant for governing inner membrane structure.

Mitochondria are the powerhouses of cells. Underneath their smooth surface they harbor an elaborately folded inner membrane. It holds a multitude of bottleneck like invaginations, which expand into elongated cavities (cristae). The narrow shape of the entrance or pore to the cristae ('crista junction') allows separation of the intracristal space and storage of molecules. Cytochrome c, for example, an important signaling protein in programmed cell death (apoptosis), is stored in this compartment.

Related Articles


When apoptosis is triggered, the pores enlarge and cytochrome c is released into the cytosol. Thus, understanding of how the pore diameter and the shape of the inner membrane are regulated on a molecular basis is of great relevance to a better understanding of mitochondrial function in general. Recently, in cooperation with other research teams, the group of Prof. Andreas Reichert, who has been appointed as professor for Mitochondrial Biology to the Goethe University within the Cluster of Excellence Macromolecular Complexes in 2007, has identified two proteins linked in an antagonistic manner that are relevant for governing inner membrane structure.

In the current issue of the the Journal of Cell Biology Rabl, Soubannier et al. report on their quest of slow-growing baker`s yeast mutants harboring deformed mitochondria. Thereby, they discovered the protein Fcj1 ("Formation of criasta junction protein 1"), which is embedded in the inner membrane and accumulates at crista junctions. Upon increased expression of Fcj1 the number of cristae junctions goes up. Without the protein, however, crista junctions are lacking and the inner cristae membrane forms internal parallel stacks of vesicles.

On the other hand, the researchers found that regular assemblies (supercomplexes) of the F1FO-ATPase, a protein complex required for supplying the cell's energy, accumulated at the cristae tips but were less abundant at crista junctions. In addition, Fcj1 and the F1FO-ATPase appear to have opposing functions. In fact, Fcj1 reduces the formation of F1FO-supercomplexes. "We hypothesize, Fcj1 makes sure that the membrane can adopt a negative curvature, while the F1FO-ATPase supercomplex induces positive bending", Andreas Reichert interprets the results. "This is highly exciting, as we have for the first time found out how mitochondrial ultrastructure is regulated and which components determine the structure of crista junctions at all."


Story Source:

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


Journal Reference:

  1. Rabl, R., Soubannier, V., Scholz, R., Vogel, F., Mendl, N., Vasiljev-Neumeyer, A., Kφrner, C., Jagasia, R., Keil, T., Baumeister, W., Cyrklaff, M., Neupert, W., and Reichert, A.S. Formation of cristae and crista junctions in mitochondria depends on antagonism between Fcj1 and Su e/g. J Cell Biol, 15th June 2009

Cite This Page:

Goethe University Frankfurt. "How Mitochondria Get Their Membranes Bent." ScienceDaily. ScienceDaily, 9 July 2009. <www.sciencedaily.com/releases/2009/06/090624153108.htm>.
Goethe University Frankfurt. (2009, July 9). How Mitochondria Get Their Membranes Bent. ScienceDaily. Retrieved December 21, 2014 from www.sciencedaily.com/releases/2009/06/090624153108.htm
Goethe University Frankfurt. "How Mitochondria Get Their Membranes Bent." ScienceDaily. www.sciencedaily.com/releases/2009/06/090624153108.htm (accessed December 21, 2014).

Share This


More From ScienceDaily



More Plants & Animals News

Sunday, December 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Researchers Test Colombian Village With High Alzheimer's Rates

Researchers Test Colombian Village With High Alzheimer's Rates

AFP (Dec. 19, 2014) — In Yarumal, a village in N. Colombia, Alzheimer's has ravaged a disproportionately large number of families. A genetic "curse" that may pave the way for research on how to treat the disease that claims a new victim every four seconds. Duration: 02:42 Video provided by AFP
Powered by NewsLook.com
Monarch Butterflies Descend Upon Mexican Forest During Annual Migration

Monarch Butterflies Descend Upon Mexican Forest During Annual Migration

Reuters - Light News Video Online (Dec. 19, 2014) — Millions of monarch butterflies begin to descend onto Mexico as part of their annual migration south. Rough Cut (no reporter narration) Video provided by Reuters
Powered by NewsLook.com
The Best Protein-Filled Foods to Energize You for the New Year

The Best Protein-Filled Foods to Energize You for the New Year

Buzz60 (Dec. 19, 2014) — The new year is coming and nothing will energize you more for 2015 than protein-filled foods. Fitness and nutrition expert John Basedow (@JohnBasedow) gives his favorite high protein foods that will help you build muscle, lose fat and have endless energy. Video provided by Buzz60
Powered by NewsLook.com
Birds Might Be Better Meteorologists Than Us

Birds Might Be Better Meteorologists Than Us

Newsy (Dec. 19, 2014) — A new study suggests a certain type of bird was able to sense a tornado outbreak that moved through the U.S. a day before it hit. 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