Article
Cytochrome c Oxidase at Full Thrust: Regulation and Biological Consequences to Flying Insect
Registro en:
MESQUITA, Rafael D. et al. Cytochrome c Oxidase at Full Thrust: Regulation and Biological Consequences to Flying Insects. Cells, v. 10, n. 470, 25 p, Feb. 2021.
2073-4409
10.3390/cells10020470
Autor
Mesquita, Rafael D.
Gaviraghi, Alessandro
Gonçalves, Renata L.S.
Santos, Marcos A. Vannier
Mignaco, Julio A.
Fontes, Carlos Frederico L.
Machado, Luciana E. S. F.
Oliveira, Marcus F
Resumen
Flight dispersal represents a key aspect of the evolutionary and ecological success of insects,
allowing escape from predators, mating, and colonization of new niches. The huge energy demand
posed by flight activity is essentially met by oxidative phosphorylation (OXPHOS) in flight muscle
mitochondria. In insects, mitochondrial ATP supply and oxidant production are regulated by several
factors, including the energy demand exerted by changes in adenylate balance. Indeed, adenylate
directly regulates OXPHOS by targeting both chemiosmotic ATP production and the activities of
specific mitochondrial enzymes. In several organisms, cytochrome c oxidase (COX) is regulated at
transcriptional, post-translational, and allosteric levels, impacting mitochondrial energy metabolism,
and redox balance. This review will present the concepts on how COX function contributes to flying
insect biology, focusing on the existing examples in the literature where its structure and activity are
regulated not only by physiological and environmental factors but also how changes in its activity
impacts insect biology. We also performed in silico sequence analyses and determined the structure
models of three COX subunits (IV, VIa, and VIc) from different insect species to compare with
mammalian orthologs. We observed that the sequences and structure models of COXIV, COXVIa,
and COXVIc were quite similar to their mammalian counterparts. Remarkably, specific substitutions
to phosphomimetic amino acids at critical phosphorylation sites emerge as hallmarks on insect COX
sequences, suggesting a new regulatory mechanism of COX activity. Therefore, by providing a
physiological and bioenergetic framework of COX regulation in such metabolically extreme models,
we hope to expand the knowledge of this critical enzyme complex and the potential consequences
for insect dispersal.