Fig. 4.

Trafficking of endogenous vacuolar markers is altered in vti12 mutants. (A) Samples of apoplastic fluid collected from Wt, vti12, and vti11 plants homozygous for the BL transgene were analyzed with anti-VacPerox and anti-BL antibodies. The same samples were silver-stained to confirm equal loading. (B) Samples of apoplastic fluid (Apo) and total protein extracts (Total) were analyzed by Western blot with antibodies against VacPerox, AtFruct4, and AtCPY (46). Plants were derived from crosses with the L1 line and were homozygous for the VAC2 transgene. Lane 1, Wt plants; lane 2, vti11/VTI11 vti12/vti12 plants. The precursor (p, 60 kDa), intermediate (i, 48 kDa), and mature (m, 24 kDa) forms of AtCPY are marked at the sides of the figures. The estimated molecular masses of VacPerox and AtFruct4 in the gels are 43 and 52 kDa, respectively. (C) Total protein extracts from siliques were analyzed by Western blot with antibodies against 12S globulins. The genotype of the mother plant is shown above the figure. Siliques were harvested 18 d after anthesis. The precursor (p) and mature (m) forms are marked at the sides of the figures. (D) PSVs imaged by confocal microscopy. Shown are epidermal cells from cotyledons dissected from dried seeds of Col-0 and enhanced (enh)vti12 plants. (Scale bar: 5 μm.)