Mass-spectrometry-based proteomics reveals mitochondrial supercomplexome plasticity

Abstract

Highlights d Comprehensive quantification of respiratory subunits within supercomplexes d Complexes II and V assemble within supercomplexes d Mitochondrial-encoded subunits display elevated upregulation upon exercise training d Exercise increases ubiquinone biosynthesis enzyme and decreases Lactb complexes

High-intensity training induces non-stoichiometric changes in the mitochondrial proteome of human skeletal muscle without reorganisation of respiratory chain content

“…We next assessed whether exercise training affects the distribution of ETC complexes into SCs. In contrast to the only previous report showing a post-training redistribution of CIII and CIV (but not CI) into SCs in elderly individuals 15 , and recent research in mouse skeletal muscle showing redistribution of CIV into SCs 54 , our analysis revealed no significant changes throughout the intervention (Fig. 5b , lower panels).…”

“…2f ; Supplementary Fig. 2d and Supplementary Data 5 ) - an enzyme with an essential role as an electron transfer lipid in OXPHOS processes 59 , which has been shown to be altered following exercise training in mouse skeletal muscle 54 . We identified changes in four constituents (COQ3, COQ5, COQ7, COQ9) of the CoQ synthome (Fig.…”

Structural basis for the catalytic activity of filamentous human serine beta-lactamase-like protein LACTB

“…Unlike its prokaryotic homologs, LACTB can polymerize into filaments within the mitochondrial inter-membrane space (Polianskyte et al, 2009). A recent mass spectrometry study demonstrated that endurance exercise training for mouse influences the polymerization degree rather than the total content of LACTB within mitochondria (Gonzalez-Franquesa et al, 2021).…”

High-Intensity Interval Training Remodels the Proteome and Acetylome of Human Skeletal Muscle

“…S3A). Furthermore, we have previously detected these adaptations in slow-and fast-twitch muscle fibers following moderate-intensity continuous cycling training (Deshmukh et al, 2021). Given that phosphorylation of myosin light chains promotes myofibrillar calcium sensitivity (Davis et al, 2001), the reduction in both MYLK2 and SMTNL1 alongside an increase in PPP1R12A indicates an adaptation towards reduced myosin phosphorylation and lowered calcium sensitivity following exercise training.…”

“…Hostrup, Onslev, Jacobson, Wilson, & Bangsbo, 2018;Majerczak, Karasinski, & Zoladz, 2008;Munkvik et al, 2010;Ortenblad, Lunde, Levin, Andersen, & Pedersen, 2000). Fast-twitch fibers have greater sarcoplasmic reticulum volume, faster calcium release and re-uptake kinetics, and a greater content of DHPR than slow-twitch fibers (Banas, Clow, Jasmin, & Renaud, 2011;Deshmukh et al, 2021;Murgia et al, 2017). Thus, the HIIT-induced reduction of DHPR abundance may represent a slowing of muscle fibers independently of their myosin heavy chain abundance.…”