Preproteins of chloroplast envelope inner membrane contain targeting information for receptor-dependent import into fungal mitochondria

authored by: Susanne Brink, Ulf Ingo Flügge, François Chaumont, Marc Boutry, Michael Emmermann, Udo Schmitz, Karin Becker, Nikolaus Pfanner
Abstract: The amino-terminal transit sequences of two preproteins destined for the chloroplast inner envelope membrane show similarities to mitochondrial presequences in the prevalence of positive charges and the potential formation of an amphipathic α-helix. We studied if these preproteins could be imported into mitochondria and found a low, yet significant import into isolated plant mitochondria. The plant mitochondria were previously shown not to import precursors of chloroplast stromal or thylakoidal proteins. To analyze the specificity of import into mitochondria we used the established import systems of fungal mitochondria. The envelope preproteins were efficiently imported into Saccharomyces cerevisiae or Neurospora crassa mitochondria. Their import showed the characteristics of specific mitochondrial protein uptake, including a requirement for the main receptor MOM19 (mitochondrial outer membrane protein of 19 kDa) and a membrane potential across the inner membrane, and depended on the presence of the chloroplast transit sequence. We conclude that some chloroplast transit sequences contain sufficient information for specific interaction with mitochondrial import receptors (at least from fungal sources).
External Organisation(s): Julius Maximilian University of Würzburg
Université catholique de Louvain (UCL)
Ludwig-Maximilians-Universität München (LMU)
Max Planck Institute of Molecular Plant Physiology (MPI-MP)
University of Freiburg
Type: Article
Journal: Journal of Biological Chemistry
Volume: 269
Pages: 16478-16485
No. of pages: 8
ISSN: 0021-9258
Publication date: 10.06.1994
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: Biochemistry, Molecular Biology, Cell Biology

BibTeX

@article{eb5e66656d6844af9ebead7dce758373,
title = "Preproteins of chloroplast envelope inner membrane contain targeting information for receptor-dependent import into fungal mitochondria",
abstract = "The amino-terminal transit sequences of two preproteins destined for the chloroplast inner envelope membrane show similarities to mitochondrial presequences in the prevalence of positive charges and the potential formation of an amphipathic α-helix. We studied if these preproteins could be imported into mitochondria and found a low, yet significant import into isolated plant mitochondria. The plant mitochondria were previously shown not to import precursors of chloroplast stromal or thylakoidal proteins. To analyze the specificity of import into mitochondria we used the established import systems of fungal mitochondria. The envelope preproteins were efficiently imported into Saccharomyces cerevisiae or Neurospora crassa mitochondria. Their import showed the characteristics of specific mitochondrial protein uptake, including a requirement for the main receptor MOM19 (mitochondrial outer membrane protein of 19 kDa) and a membrane potential across the inner membrane, and depended on the presence of the chloroplast transit sequence. We conclude that some chloroplast transit sequences contain sufficient information for specific interaction with mitochondrial import receptors (at least from fungal sources).",
author = "Susanne Brink and Fl{\"u}gge, {Ulf Ingo} and Fran{\c c}ois Chaumont and Marc Boutry and Michael Emmermann and Udo Schmitz and Karin Becker and Nikolaus Pfanner",
year = "1994",
month = jun,
day = "10",
language = "English",
volume = "269",
pages = "16478--16485",
journal = "Journal of Biological Chemistry",
issn = "0021-9258",
publisher = "American Society for Biochemistry and Molecular Biology Inc.",
number = "23",
}