title: Mitochondrial membrane potential and ATP production in primary disorders of ATP synthase.
abstract: Studies of fibroblasts with primary defects in mitochondrial ATP synthase (ATPase) due to heteroplasmic mtDNA mutations in the ATP6 gene, affecting protonophoric function or synthesis of subunit a, show that at high mutation loads, mitochondrial membrane potential DeltaPsi(m) at state 4 is normal, but ADP-induced discharge of DeltaPsi(m) is impaired and ATP synthesis at state 3-ADP is decreased. Increased DeltaPsi(m) and low ATP synthesis is also found when the ATPase content is diminished by altered biogenesis of the enzyme complex. Irrespective of the different pathogenic mechanisms, elevated DeltaPsi(m) in primary ATPase disorders could increase mitochondrial production of reactive oxygen species and decrease energy provision.
authors.affiliation: Institute of Physiology and Centre for Integrated Genomics, Academy of Sciences of the Czech Republic, Prague, Czech Republic.
authors.forename: Alena
authors.initials: A
authors.lastname: Vojtísková
authors.forename: Pavel
authors.initials: P
authors.lastname: Jesina
authors.forename: Martin
authors.initials: M
authors.lastname: Kalous
authors.forename: Vilma
authors.initials: V
authors.lastname: Kaplanová
authors.forename: Josef
authors.initials: J
authors.lastname: Houstek
authors.forename: Markéta
authors.initials: M
authors.lastname: Tesarová
authors.forename: Daniela
authors.initials: D
authors.lastname: Fornůsková
authors.forename: Jirí
authors.initials: J
authors.lastname: Zeman
authors.forename: Audrey
authors.initials: A
authors.lastname: Dubot
authors.forename: Catherine
authors.initials: C
authors.lastname: Godinot