Homologous and heterologous protein import into mitochondria isolated from the green alga Chlamydomonas reinhardtii.
We have established a homologous system for studying mitochondrial protein import in Chlamydomonas reinhardtii, using C. reinhardtii precursor proteins and mitochondria isolated from C. reinhardtii. The precursors of the F1 alpha ATP synthase subunit and the Rieske FeS protein were imported into mitochondria with high efficiency, while the F1 beta subunit precursor was imported with much lower efficiency. The import of heterologous precursor proteins from higher plants was also less efficient. The precursor of the C. reinhardtii PsaF chloroplast protein was converted into a protease-protected form upon incubation with mitochondria. In vitro processing studies revealed that in contrast to the situation in higher plants, the processing of the precursors was catalysed by a soluble, matrix-located peptidase.
Nurani
G
G
Department of Biochemistry, Arrhenius Laboratories, Stockholm University, Sweden.
Eriksson
M
M
Knorpp
C
C
Glaser
E
E
Franzén
L G
LG
D000818:Animals; D001692:Biological Transport; D016825:Chlamydomonas reinhardtii / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000302:isolation & purification; D014450:Electron Transport Complex III; D007506:Iron-Sulfur Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D008928:Mitochondria / Q000201:enzymology / Q000378:metabolism*; D011498:Protein Precursors / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D017433:Protein Structure, Secondary; D006180:Proton-Translocating ATPases / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism
D018076:DNA, Complementary; D007506:Iron-Sulfur Proteins; D011498:Protein Precursors; C037989:Rieske iron-sulfur protein; D006180:Proton-Translocating ATPases; D014450:Electron Transport Complex III