Researchers discover a new basic principle of the mitochondria architecture

September 14, 2012, Albert Ludwigs University of Freiburg
The protein complex MINOS plays a key role in the formation of the two membrane systems of mitochondria. MINOS is necessary for the architecture of the inner membrane and helps TOM and SAM embed proteins in the outer membrane by forming membrane bridges. Credit: Ralf Zerbes

A team of scientists at the University of Freiburg led by Dr. Martin van der Laan has achieved groundbreaking new insights into the structure of mitochondria. Mitochondria are the microscopic power plants of the cell that harness the energy stored in food, thus enabling central life functions. This conversion of energy takes place in delicately formed cavities of the biological membranes inside mitochondria. Defects in these fine membrane structures can lead to severe diseases of the muscles and the central nervous system. A sophisticated molecular machine of the inner membrane that the Freiburg team already discovered in 2011 is not only responsible for forming the characteristic structures within mitochondria but evidently also plays an important role in assembling the outer membrane enclosing these organelles, as the scientists now report in the renowned journal Molecular Biology of the Cell.

The protein machine studied by the scientists is essential for maintaining the typical architecture inside the and have thus received the name "Mitochondrial Organizing System" (MINOS). In their latest study, the Freiburg researchers and their colleagues in Graz, Austria, Warsaw, Poland, and Groningen, Netherlands, demonstrate that the role of MINOS in creating the mitochondrial architecture is clearly more extensive than previously assumed. In a joint research effort between the Collaborative Research Center 746 and the Cluster of Excellence Centre for Biological Signalling Studies (BIOSS), Dr. Maria Bohnert, Lena-Sophie Wenz and Ralf Zerbes found out how MINOS connects the distinct membrane systems of the mitochondria with each other.

The membrane complexes SAM and TOM play a key role in this process. They use tunnel-shaped structures to transport proteins into the mitochondrion and then embed them in the outer membrane. In their latest study, the Freiburg scientists demonstrate that the MINOS component Fcj1 of the Mitofilin participates directly in this process, which is essential for the survival of the cells. The inactivation of Fcj1 inhibits the integration of proteins into the mitochondrial outer membrane. These findings show how molecular switches affecting the connectivity of mitochondrial membranes control the assembly and function of the cellular power plants. These newly gained insights improve our understanding of the basic principles of the architecture of mitochondria. In the future they could help scientists to understand and influence mechanisms of diseases that involve changes in the fine structure of mitochondria.

Explore further: New mitochondria mechanism identified

More information: Bohnert M, Wenz LS, Zerbes RM, Horvath SE, Stroud DA, von der Malsburg K, Müller JM, Oeljeklaus S, Perschil I, Warscheid B, Chacinska A, Veenhuis M, van der Klei IJ, Daum G, Wiedemann N, Becker T, Pfanner N, van der Laan M: "Role of MINOS in protein biogenesis of the mitochondrial outer membrane", in: Molecular Biology of the Cell, published online August 23, 2012. … 8/20/mbc.E12-04-0295

Related Stories

New mitochondria mechanism identified

September 27, 2011

A team of researchers led by the University of Freiburg in Germany has identified a novel mechanism that plays a key role in the architecture and functioning of mitochondria - the power plants of the cell, giving cells the ...

Cell death pathway linked to mitochondrial fusion

January 24, 2011

New research led by UC Davis scientists provides insight into why some body organs are more susceptible to cell death than others and could eventually lead to advances in treating or preventing heart attack or stroke.

How mitochondria get their membranes bent

June 24, 2009

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 ...

New mitochondrial control mechanism discovered

May 4, 2011

Scientists have discovered a new component of mitochondria that plays a key part in their function. The discovery, which is presented in the journal Cell Metabolism, is of potential significance to our understanding of both ...

New insight in how cells' powerhouse divides

September 2, 2011

New research from the University of California, Davis, and the University of Colorado at Boulder puts an unexpected twist on how mitochondria, the energy-generating structures within cells, divide. The work, which could have ...

Recommended for you

Predators learn to identify prey from other species

March 21, 2018

Wolves purportedly raised Romulus and Remus, who went on to rule Rome. Is there good scientific evidence for learning across species? Researchers at the Smithsonian Tropical Research Institute (STRI) in Panama wanted to know ...

Insects could help us find new yeasts for big business

March 21, 2018

Yeasts are tiny fungi - but they play key roles in producing everything from beer and cheese to industrial chemicals and biofuels. And now scientists are proposing a new approach that could help these industries find new ...

Promiscuity may have accelerated animal domestication

March 21, 2018

Domestication of wild animals may have accelerated as promiscuity increased among the high density populations drawn to life near humans, according to a new paper by University of Liverpool researchers.


Adjust slider to filter visible comments by rank

Display comments: newest first

1.3 / 5 (14) Sep 14, 2012
Notice how the researchers do not mention anything about evolution in this story. The reason is quite clear and simple: firstly it contributes absolutely nothing to the research and secondly it should be absolutely clear that the irreducible complexity involved rules out any random, step by step development. ESPECIALLY since life wouldn't even begin to exist without the mitochondria.
3 / 5 (8) Sep 14, 2012
shut the fuck up kevin, we are tired of your strawmans. go read your bible or pray to your god for us lowly heathens if you love and believe in it so desperately.
5 / 5 (2) Sep 14, 2012
life wouldn't even begin to exist without the mitochondria
Life probably evolved in anaerobic environment, so that mitochondria evolved later, when photosynthetic bacteria increased the concentration of oxygen in the atmosphere. According to Lynn Margulius the composition of mitochondrial membranes provides a clue of their endosymbiotic origin: they're cells of former green bacteria, which lost their photosynthetic dyes and which were used with reversed function of their ATP pumps.
5 / 5 (4) Sep 14, 2012
Creationists shouldn't comment on science, it is hilarious to see.

Bacteria and Archaea has no mitochondrion endosymbionts, which themselves are of bacterial origin.

The reason evolution isn't much mentioned is because it is a functional study. But it describe evolution in the abstract: "Mitochondria lacking mitofilin, the large core subunit of MINOS, are impaired in the biogenesis of β-barrel proteins of the outer membrane, whereas mutant mitochondria lacking any of the other five MINOS subunits import β-barrel proteins like wild-type mitochondria." So they used evolutionary mechanisms to study the biological system.

A result that crushes remaining hopes of creationists was presented yesterday. It turns out Viruses is a 4th domain of life and is the missing piece that unifies and roots the tree. See especially fig 3, that shows the new ToL. [ http://www.biomed...-156.pdf ] Now all biological systems are rooted in an evolutionary LUCA!
5 / 5 (3) Sep 15, 2012
Errr. Kevin my little Tard.

The cells comprising most life on earth have no mitochondria.

Did you fail grade 9 Biology?

"ESPECIALLY since life wouldn't even begin to exist without the mitochondria." - KevinTard

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.