Figure 8

Membrane topology of plant VHA-a and location of the C-termini of individual subunits based on the FRET data. Based on amino acid sequence analysis and similarity with Vph1 (Leng et al. 1999), the topology of Mc-VHA-a is depicted in (A). The relative location of amino acid residues essential for proton pumping or structure are indicated with boxes. The numbers indicate the amino acid positions. In (B), the results from the FRET experiments are summarized: Asterisks tentatively mark the positions of the C-termini where the GFP variants have been fused to.