Format

Send to

Choose Destination
J Biol Chem. 2002 Nov 15;277(46):43553-6. Epub 2002 Oct 2.

Gluing the respiratory chain together. Cardiolipin is required for supercomplex formation in the inner mitochondrial membrane.

Author information

1
Department of Biochemistry and Molecular Biology, University of Texas Medical School, Houston 77225, USA.

Abstract

Cytochrome bc(1) complex (complex III) and cytochrome c oxidase complex (complex IV) are multisubunit homodimers that are essential components of the mitochondrial respiratory chain. Complexes III and IV associate to form a supercomplex that can be displayed using blue native polyacrylamide gel electrophoresis. Both homodimeric complexes contain tightly associated cardiolipin (CL) required for function. We report here that in a crd1Delta strain of yeast (null in expression of CL synthase) approximately 90% of complexes III and IV were observed as individual homodimers; only the supercomplex was observed with CRD1 wild type cells. Introduction of a plasmid born copy of the CRD1 gene under exogenous regulation by doxycycline made possible controlled variation in the in vivo CL levels. At an intermediate level of CL, a mixture of individual homodimers (30%) and supercomplex (70%) was observed. These results strongly indicate that CL plays a central role in higher order organization of components of the respiratory chain of mitochondria.

PMID:
12364341
DOI:
10.1074/jbc.C200551200
[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for HighWire
Loading ...
Support Center