Figure 6.

TMD length or hydrophobicity is a critical determinant for mitochondria localization. (A) Schematic presentation of rTom20-GFP constructs in which the NH₂-terminal hydrophilic segment and the TMD were replaced by those of Syt II (ST27 and ST20), leucine repeats were inserted into the TMD (H20, H22 and H24), or glycine or tyrosine residues in the TMD were replaced by leucine residues (Hydrophobic-1 and -2). Hydrophobicity, hydropathic index/residue; Mit, mitochondria; PM, plasma membrane. (B) Localization of ST27 and ST20 in COS-7 cells. Confocal images of GFP (green) and MitoTracker (red) are shown. (C) Mitochondria localization of rTom20-GFP fusions depends on the TMD length or hydrophobicity. The indicated rTom20-GFP constructs were expressed in COS-7 cells. The cells were costained with MitoTracker and fluorescence images were taken by a confocal microscope.