In:
eLife, eLife Sciences Publications, Ltd, Vol. 6 ( 2017-08-31)
Kurzfassung:
The cells of animals, plants and other eukaryotic organisms contain compartments known as organelles that play many different roles. For example, compartments called mitochondria are responsible for supplying the chemical energy cells need to survive and grow. Two membranes surround each mitochondrion and energy is converted on the surface of the inner one. Mitochondria contain over 1,000 different proteins, most of which are produced in the main part of the cell and have to be transported into the mitochondria. A transport protein called Tim23 is part of a larger group or ‘complex’ of proteins that helps to import many other proteins into the mitochondria. This complex sits in the inner membrane, with the Tim23 protein forming a large, water-filled pore through its core that provides a route for proteins to pass through the membrane. Proteins are made of building blocks called amino acids. The proteins transported by the complex containing Tim23 all have a short chain of amino acids at one end known as an N-terminal presequence. However, it is not clear how the inside of the Tim23 channel identifies and transports this presequence to allow the right proteins to pass through the inner membrane. Denkert, Schendzielorz et al. studied the normal and mutant versions of a Tim23 channel from yeast to find out which parts of the protein are involved in detecting the N-terminal presequence after it enters the pore. The experiments show that there are several amino acids in Tim23 that play important roles in this process. Furthermore, mitochondria containing mutant Tim23 channels, that are less able to identify the N-terminal presequence, are impaired in their ability to import proteins. Tim23 proteins in humans and other organisms also contain most or all of the specific amino acids identified in this study, suggesting that the findings of Denkert, Schendzielorz et al. will also apply to other species. Furthermore, the experimental strategy used in this study could be adapted to investigate transport proteins in other cell compartments.
Materialart:
Online-Ressource
ISSN:
2050-084X
DOI:
10.7554/eLife.28324.001
DOI:
10.7554/eLife.28324.002
DOI:
10.7554/eLife.28324.003
DOI:
10.7554/eLife.28324.004
DOI:
10.7554/eLife.28324.005
DOI:
10.7554/eLife.28324.006
DOI:
10.7554/eLife.28324.007
DOI:
10.7554/eLife.28324.008
DOI:
10.7554/eLife.28324.009
DOI:
10.7554/eLife.28324.010
DOI:
10.7554/eLife.28324.011
DOI:
10.7554/eLife.28324.012
DOI:
10.7554/eLife.28324.013
DOI:
10.7554/eLife.28324.014
Sprache:
Englisch
Verlag:
eLife Sciences Publications, Ltd
Publikationsdatum:
2017
ZDB Id:
2687154-3
