QCR9

QCR9 is a component of the mitochondrial coenzyme Q:cytochrome c oxidoreductase complex (Complex III) in Toxoplasma gondii, identified by mass spectrometry-based proteomics of the purified complex, which comprises both canonical subunits conserved across eukaryotes and divergent apicomplexan-specific subunits (PMID:33524071). Beyond this assignment as a Complex III subunit, no further mechanistic detail about QCR9's specific function has been characterized in the available corpus.

1. 2021 Medium

   Whether QCR9 associates with the respiratory Complex III in an apicomplexan parasite was unknown; proteomic dissection of the purified complex established QCR9 as a bona fide subunit alongside conserved and lineage-specific components.

   Evidence Mass spectrometry-based proteomics of purified Complex III in Toxoplasma gondii

   PMID:33524071

   Open questions at the time

   • No direct functional validation of QCR9's role within Complex III
   • Position and interaction partners of QCR9 within the complex not resolved
   • Contribution of QCR9 to complex assembly, stability, or electron transfer not tested