FIGURE 5.

Mechanistic study of TID1 overexpression-caused changes in frataxin levels. HEK293 cells transfected with frataxin and TID1 plasmid DNAs were subject to mitochondria fractionation followed by Western blotting analysis. Frataxin precursor is predominantly localized in the mitochondrial fraction upon TID1L or TID1S overexpression (A). Tom20 was used as a mitochondrial marker (A). Treatment with MG132 (10 μM) also had no effect on TID1L or TID1S overexpression-caused decrease in intermediate and mature frataxin (B). Frataxin G130V mutant transfected HEK293 cells were used as a positive control (B). Neither TID1L nor TID1S interacted with MPP, in contrast to GRP75 (C).