Scaf1 promotes respiratory supercomplexes and metabolic efficiency in zebrafish García Poyatos, Carolina Cogliati, Sara Metabolism Mitochondria OXPHOS super-assembly SCAF1/COX7A2L Zebrafish The oxidative phosphorylation (OXPHOS) system is a dynamic system in which the respiratory complexes coexist with superassembled quaternary structures called supercomplexes (SCs). The physiological role of SCs is still disputed. Here, we used zebrafish to study the relevance of respiratory SCs. We combined immunodetection analysis and deep data-independent proteomics to characterize these structures and found similar SCs to those described in mice, as well as novel SCs including III2 + IV2, I + IV, and I + III2 + IV2. To study the physiological role of SCs, we generated two null allele zebrafish lines for supercomplex assembly factor 1 (scaf1). scaf1 / fish displayed altered OXPHOS activity due to the disrupted interaction of complexes III and IV. scaf1 / fish were smaller in size and showed abnormal fat deposition and decreased female fertility. These physiological phenotypes were rescued by doubling the food supply, which correlated with improved bioenergetics and alterations in the metabolic gene expression program. These results reveal that SC assembly by Scaf1 modulates OXPHOS efficiency and allows the optimization of metabolic resources. 2020-11-10T08:31:36Z 2020-11-10T08:31:36Z 2020 info:eu-repo/semantics/article García‐Poyatos, C., Cogliati, S., Calvo, E., Hernansanz‐Agustín, P., Lagarrigue, S., Magni, R., ... & Mercader, N. (2020). Scaf1 promotes respiratory supercomplexes and metabolic efficiency in zebrafish. EMBO reports, e50287. [DOI 10.15252/embr.202050287] http://hdl.handle.net/10481/64158 10.15252/embr.202050287 eng http://creativecommons.org/licenses/by/3.0/es/ info:eu-repo/semantics/openAccess Atribución 3.0 España WILEY