Figure 4.

N135 can import MDR1 and SytII into the mitochondria. (A) N-terminal 140-residues sequence was fused to the Asn²¹ of MDR1 (N140-MDR1). Three potential endogenous glycosylation sites between H1 and H2 are indicated by circles. (B and C) Localizations and intracellular topology were assessed as noted in Figure 2. Staining with ER marker (calnexin) also was performed. In lanes 5, 6 11, and 12, aliquots of membrane fractions were treated with either PNGaseF (PF) or Endo H (EH) to remove sugar chains. (D) N-terminal 140-residues sequence was fused to SytII at Asn⁵⁰ (N140-SytII). Glycosylation sites are indicated by circles. (E and F) Localization and topology were assessed as noted in Figure 2. The di-, mono-, and unglycosylated forms are indicated (gg, g, and p, respectively).