Figure 6
OmpX and 2xOmpX are similarly dependent on chaperones.
(a,b) Crude mitochondria were isolated from Tob55-depleted cells co-expressing OmpX (a) or 2xOmpX (b) and either plasmid-encoded Tob55 or the indicated hybrid protein. Proteins were analyzed by SDS-PAGE and immunodetection with the indicated antibodies. (c) The bands of at least three experiments as those described in (a) and (b) were quantified and their means ± s.d. are presented. To allow comparison among the various samples, the levels of Tom20 were taken as internal reference. The intensities of the bands from cells transformed with native Tob55 (construct A) were set to 100%. **p value < 0.01. (d,e) Crude mitochondria were isolated from Tob55-depleted cells co-expressing OmpX, the indicated Tob55 variant, and either SurA or Skp. Further treatment and analysis were as described in the legends to Fig. 5 parts (a) and (b). (f,g) Crude mitochondria were isolated from Tob55-depleted cells co-expressing 2xOmpX, the indicated Tob55 variant, and either SurA or Skp. Further treatment and analysis were as described in the legends to Fig. 5 parts (a) and (b). (h) Mitochondria (Total, T) were isolated from cells co-expressing plasmid-encoded native Tob55 (construct A) and OmpX in the presence or absence of Skp. The organelles were subjected to alkaline extraction separating membrane-embedded proteins in the pellet (P) from soluble proteins in the supernatant (S). Proteins were analyzed by SDS-PAGE and immunodecoration with the indicated antibodies. A schematic representation of the relevant Tob55 variants is included.
