The spatio-temporal organization of mitochondrial F1FO ATP synthase in cristae depends on its activity mode
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Show full item recordEditorial
Elsevier BV
Materia
Mitochondria Spatio-temporal organization Superresolution microscopy Ultrastructure Metabolic adaptation
Date
2019-11-27Referencia bibliográfica
Salewskij, K., Rieger, B., Hager, F., Arroum, T., Duwe, P., Villalta, J., ... & Dellmann, T. (2020). The spatio-temporal organization of mitochondrial F1FO ATP synthase in cristae depends on its activity mode. Biochimica et Biophysica Acta (BBA)-Bioenergetics, 1861(1), 148091.
Sponsorship
This work was supported by the DFG (INST 190/167-2).Abstract
F1FO ATP synthase, also known as complex V, is a key enzyme of mitochondrial energy metabolism that can
synthesize and hydrolyze ATP. It is not known whether the ATP synthase and ATPase function are correlated
with a different spatio-temporal organisation of the enzyme. In order to analyze this, we tracked and localized
single ATP synthase molecules in situ using live cell microscopy. Under normal conditions, complex V was mainly
restricted to cristae indicated by orthogonal trajectories along the cristae membranes. In addition confined
trajectories that are quasi immobile exist. By inhibiting glycolysis with 2-DG, the activity and mobility of
complex V was altered. The distinct cristae-related orthogonal trajectories of complex V were obliterated.
Moreover, a mobile subpopulation of complex V was found in the inner boundary membrane. The observed
changes in the ratio of dimeric/monomeric complex V, respectively less mobile/more mobile complex V and its
activity changes were reversible. In IF1-KO cells, in which ATP hydrolysis is not inhibited by IF1, complex V was
more mobile, while inhibition of ATP hydrolysis by BMS-199264 reduced the mobility of complex V. Taken
together, these data support the existence of different subpopulations of complex V, ATP synthase and ATP
hydrolase, the latter with higher mobility and probably not prevailing at the cristae edges. Obviously, complex V
reacts quickly and reversibly to metabolic conditions, not only by functional, but also by spatial and structural
reorganization.