Proteomic Approach to Identify Novel Mitochondrial Proteins in Arabidopsis

authored by
Volker Kruft, Holger Eubel, Lothar Jänsch, Wolf Werhahn, Hans Peter Braun
Abstract

An Arabidopsis mitochondrial proteome project was started for a comprehensive investigation of mitochondrial functions in plants. Mitochondria were prepared from Arabidopsis stems and leaves or from Arabidopsis suspension cell cultures, and the purity of the generated fractions was tested by the resolution of organellar protein complexes applying two-dimensional blue-native/N-[2-hydroxy-1,1-bis(hydroxymethyl)ethyl]glycine (Tricine) sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The Arabidopsis mitochondrial proteome was analyzed by two-dimensional isoelectric focusing/ Tricine sodium dodecyl sulfate-polyacrylamide gel electrophoresis and 650 different proteins in a pI range of pH 3 to 10 were separated on single gels. Solubilization conditions, pH gradients for isoelectric focusing, and gel staining procedures were varied, and the number of separable proteins increased to about 800. Fifty-two protein spots were identified by immunoblotting, direct protein sequencing, and mass spectrometry. The characterized proteins cooperate in various processes, such as respiration, citric acid cycle, amino acid and nucleotide metabolism, protection against O2

, mitochondrial assembly, molecular transport, and protein biosynthesis. More than 20% of the identified proteins were not described previously for plant mitochondria, indicating novel mitochondrial functions. The map of the Arabidopsis mitochondrial proteome should be useful for the analysis of knockout mutants concerning nuclear-encoded mitochondrial genes. Considerations of the total complexity of the Arabidopsis mitochondrial proteome are discussed. The data from this investigation will be made available at www.gartenbau.uni-harnnover.de/genetik/AMPP.

Organisation(s)
Section Plant Molecular Biology and Plant Proteomics
Institute of Plant Genetics
Type
Article
Journal
Plant physiology
Volume
127
Pages
1694-1710
No. of pages
17
ISSN
0032-0889
Publication date
01.2001
Publication status
Published
Peer reviewed
Yes
ASJC Scopus subject areas
Physiology, Genetics, Plant Science
Electronic version(s)
https://doi.org/10.1104/pp.010474 (Access: Open)