Cox11 Conditional Knockout mouse models

Cox11, ortholog of human COX11, encodes an inner membrane metallochaperone that receives copper from the intermembrane space carrier Cox17 through conserved cysteine thiols and inserts it into the CuB site of MT-CO1, the site that together with heme a3 forms the binuclear oxygen reduction center of cytochrome c oxidase. Because CuB delivery occurs as MT-CO1 is being inserted, loss of Cox11 arrests complex IV assembly at an early module and triggers turnover of unmetalated subunit 1, yielding isolated cytochrome c oxidase deficiency rather than a partial activity defect. That places the design fork between a conditional null, which produces tissue restricted COX deficiency, and cysteine substitution knockins, which test metal transfer chemistry specifically. Sco1, Sco2, and Cox19 act on the CuA site and do not substitute for CuB delivery. Use Ckmm-Cre or Nes-Cre with COX histochemistry, mitochondrial copper measurements, and blue native profiling of assembly intermediates.

Cox11 conditional knockout mice carry a floxed allele so you delete function only where Cre is active. The germline allele stays intact until you cross to a tissue specific Cre. Labs reach for this design when a global knockout is lethal, when they need adult onset loss, or when regional redundancy hides a whole body phenotype.