Figure 10.

AtVTI1a associates with AtPEP12p. Postnuclear supernatant from three grams of T7-AtVTI1a transgenic or wild-type Arabidopsis plants (21 d old) were treated with 1% Triton X-100 to solubilize membrane proteins. An aliquot was saved as total protein. The Triton X-100–solubilized protein extract was then incubated with 100 μl of T7 antibody agarose (Novagen) for 5 h. Beads were pelleted, and the flow-through was collected. After being washed, proteins associated with the T7 antibody agarose were eluted. Equal volumes of total (T), flow-through (FT), and eluate (E) were separated by SDS-PAGE, followed by immunoblotting with antibodies against AtVTI1a, AtPEP12p, or AtELP.