Othonicar 2023 MiPschool Obergurgl
Mitochondrial alternative enzymes and supercomplexes: functional and evolutionary insights. |
Link: MiPschool Obergurgl 2023
Othonicar Murilo F (2023)
Event: MiPschool Obergurgl 2023
Authors: Othonicar Murilo F, Garcia Geovana S, Oliveira Marcos Tulio
Oxidative phosphorylation (OXPHOS) dysfunction can lead to decreased ATP levels and excessive reactive oxygen species (ROS) formation. Alternative enzymes (AEs) have been successfully used in model organisms to bypass OXPHOS defects and prevent high ROS levels, despite vertebrates and insects having lost their coding genes throughout evolution [1,2,3]. To get a deeper insight into the possible differences between AE-bearing and -lacking animals, we compared the genes coding for subunits of the OXPHOS complexes in tunicates of the genus Ciona with orthologs in Drosophila and humans. We found that Ciona species lack subunits necessary for the formation of respiratory supercomplexes (SCs), which are supramolecular organizations of the invidual OXPHOS complexes able to streamline electron transfer and prevent excessive ROS formation[4]. This suggests that Ciona species do not form SCs, or do so differently. In agreement, we also found that the Ciona intestinalis AE alternative oxidase (AOX), when transgenically expressed in Drosophila melanogaster, preferentially receives electrons from the mitochondrial glycerol-3-phosphate dehydrogenase, which is not known to be involved in SCs. Only when Drosophila SCs appear to be disrupted, AOX is able to receive all electrons from Complex I, a well known SC component. We are currently investigating SC formation in AOX-expressing flies and in C. intestinalis. Our findings could offer valuable insights for optimizing AOX expression in possible future therapeutic settings, and shed light on the evolutionary and functional variations between animal OXPHOS systems.
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β’ Keywords: Mitochondria, alternative enzymes, supercomplex, Ciona, Drosophila
β’ O2k-Network Lab: BR Jaboticabal Oliveira MT
Affiliation and acknowledgements
- Othonicar Murilo F, Garcia Geovana S, Oliveira Marcos Tulio
- Department of Biotechnology, School of Agricultural and Veterinary Sciences, UNESP- SΓ£o Paulo State University, Jaboticabal, SP, Brazil
- Corresponding author: [email protected]
- Funding: FAPESP(grant 2021/06711-2, 2022/01509-3) and CNPQ(grant 141001/2019-4)
Labels: MiParea: Comparative MiP;environmental MiP
Organism: Human, Drosophila, Other invertebrates
Event: Poster