MICOS and F1FO-ATP synthase crosstalk is a fundamental property of mitochondrial cristae

ABSTRACT: Mitochondrial cristae are polymorphic invaginations of the inner membrane that are the fabric of cellular respiration. Both the Mitochondrial Contact Site and Cristae Organization System (MICOS) and the F1FO-ATP synthase are vital for sculpting cristae by opposing membrane bending forces. While MICOS promotes negative curvature at cristae junctions, dimeric F1FO-ATP synthase is crucial for positive curvature at cristae rims. Crosstalk between these two complexes has been observed in baker’s yeast, the model organism of the Opisthokonta supergroup. Here, we report that this property is conserved in Trypanosoma brucei, a member of the Discoba supergroup that separated from Opisthokonta ~2 billion years ago. Specifically, one of the paralogs of the core MICOS subunit Mic10 interacts with dimeric F1FO-ATP synthase, whereas the other core Mic60 subunit has a counteractive effect on F1FO-ATP synthase oligomerization. This is evocative of the nature of MICOS-F1FO-ATP synthase crosstalk in yeast, which is remarkable given the diversification these two complexes have undergone during almost 2 eons of independent evolution. Furthermore, we identified a highly diverged trypanosome homolog of subunit e, which is essential for the stability of F1FO-ATP synthase dimers in yeast. Just like subunit e, it is preferentially associated with dimers, interacts with Mic10 and its silencing results in severe defects to cristae and disintegration of F1FO-ATP synthase dimers. Our findings indicate that crosstalk between MICOS and dimeric F1FO-ATP synthase is a fundamental property impacting cristae shape throughout eukaryotes.

INSTRUMENT(S): Orbitrap Fusion

ORGANISM(S): Trypanosoma Brucei Brucei Treu927

SUBMITTER: Karel Harant  

LAB HEAD: Hassan Hashimi

PROVIDER: PXD025109 | Pride | 2021-06-15

REPOSITORIES: Pride