A receptor for protein import into potato mitochondria

authored by
Lisa Heins, Udo Schmitz
Abstract

Five potential surface receptors for protein import into plant mitochondria were identified by gentle trypsin treatment of intact mitochondria from potato tubers and subsequent preparation of outer mitochondrial membranes. One of them, a 23 kDa protein, was purified to homogeneity and analysed by direct protein sequencing. Copy DNA clones encoding the corresponding polypeptide were isolated with labelled oligonucleotides derived from the amino acid data. The 23 kDa protein shares significant sequence similarity with protein import receptors from fungal mitochondria and contains one of their typical tetratricopeptide motifs. Its integration into the outer membrane is independent of protease accessible surface receptors and not accompanied by proteolytic processing. Monospecific antibodies against the 23 kDa protein significantly reduce import capacity of isolated mitochondria indicating that this component is indeed involved in the recognition or import of precursor proteins. As in fungi, immunological inhibition of protein import with IgGs against a single receptor is incomplete suggesting the existence of other receptors in the outer mitochondrial membrane of plant mitochondria.

External Organisation(s)
Max Planck Institute of Molecular Plant Physiology (MPI-MP)
Type
Article
Journal
Plant Journal
Volume
9
Pages
829-839
No. of pages
11
ISSN
0960-7412
Publication date
06.1996
Publication status
Published
Peer reviewed
Yes
ASJC Scopus subject areas
Genetics, Plant Science, Cell Biology
Electronic version(s)
https://doi.org/10.1046/j.1365-313X.1996.9060829.x (Access: Unknown)