Fig 6.

Physical association with and supporting activity of the COX enzyme are a conserved feature of Hig1 proteins. (A) Ni-NTA purification of Rcf1_His and Rcf1ΔC_His following solubilization with Triton X-100. See Fig. 1B for further details. (B) COX enzyme activity measurements in mitochondria isolated from wild-type and Δrcf1 Δrcf2 strains harboring Rcf1_His or the C. elegans Hig1 homolog M05D6.5_His, as described for Fig. 3B. (C) Purification of Rcf1_His and M05D6.5_His from the Δrcf1 Δrcf2 strain performed under Triton X-100 solubilization conditions and analyzed by SDS-PAGE and silver staining (top) or in parallel by immunodecoration for Cox2, Cox6, and Cox12 subunits (bottom). The positions of COX subunits, Rcf1_His, and M05D6.5_His (and a smaller proteolytic fragment of this protein, f-M05D6.5_His) on the silver-stained gel, verified by immunodecoration, are indicated.