New perspectives on the assembly process of mitochondrial respiratory chain complex cytochrome c oxidase.
The assembly of cytochrome c oxidase (COX) is a complicated process and requires a number of assembly factors to put all the necessary subunits in the correct position. Defects in COX assembly lead in particular to serious neuromuscular disorders. We demonstrated that COX-deficient patients can be associated with different assembly patterns. To obtain more insight in the biogenesis of COX in a living cell, we used yeast as a model organism to design a way to pulse label holo-COX with green fluorescent protein (GFP). Using blue native electrophoresis, we showed that the GFP-tagged subunit is incorporated into fully assembled COX and this GFP tagged complex still has enzymatic activity. This allows us to correlate the GFP fluorescence signal detected in vivo by microscopy with the synthesis, turnover and assembly of COX.
Ugalde
Cristina
C
Department of Paediatrics, Nijmegen Centre for Mitochondrial Disorders, University Medical Centre Nijmegen, P.O. Box 9101, 6500 HB Nijmegen, The Netherlands.
Coenen
Marieke J H
MJ
Farhoud
Murtada H
MH
Gilinsky
Stefanie
S
Koopman
Werner J H
WJ
van den Heuvel
Lambert P
LP
Smeitink
Jan A M
JA
Nijtmans
Leo G J
LG