Maintenance of Complex I and respiratory super-complexes by NDUF-11 is essential for respiratory function, mitochondrial structure and health in C. elegans

Knapp-Wilson, A.; Pereira, G. C.; Buzzard, E.; Corey, R. A.; Richardson, A. P.; Neal, C.; Verkade, P.; Halestrap, A. P.; Gold, V.; Kuwabara, P.; Collinson, I.

doi:10.1101/2021.01.06.425530

bioRxiv · 10.1101/2021.01.06.425530

Maintenance of Complex I and respiratory super-complexes by NDUF-11 is essential for respiratory function, mitochondrial structure and health in C. elegans

Knapp-Wilson, A.·Pereira, G. C.·Buzzard, E.·Corey, R. A.·Richardson, A. P.·Neal, C.·Verkade, P.·Halestrap, A. P.·Gold, V.·Kuwabara, P.·Collinson, I.

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Abstract

Mitochondrial super-complexes form around a conserved core of monomeric complex I and dimeric complex III; wherein subunit NDUFA11, of the former, is conspicuously situated at the interface. We identified B0491.5 (NDUF-11) as the C. elegans homologue, of which animals homozygous for a CRISPR-Cas9 generated knockout allele arrested at the L2 development stage. Reducing expression by RNAi allowed development to the adult stage, enabling characterisation of the consequences: destabilisation of complex I and its super-complexes, and perturbation of respiratory function. The loss of NADH-dehydrogenase activity is compensated by enhanced complex II activity, resulting in excessive detrimental ROS production. Meanwhile, electron cryo-tomography highlight aberrant cristae morphology and widening of the inter-membrane space and cristae junctions. The requirement of NDUF-11 for balanced respiration, mitochondrial morphology and development highlights the importance of complex I/ super-complex maintenance. Their perturbation by this, or other means, is likely to be the cause of metabolic stress and disease.

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Knapp-Wilson, A., Pereira, G. C., Buzzard, E., Corey, R. A., Richardson, A. P., Neal, C., Verkade, P., Halestrap, A. P., Gold, V., Kuwabara, P., Collinson, I.. 2021-01-06. Maintenance of Complex I and respiratory super-complexes by NDUF-11 is essential for respiratory function, mitochondrial structure and health in C. elegans. https://doi.org/10.1101/2021.01.06.425530

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